M i c h i gan State University A g r i c u l tural Experiment Station In Cooperation with the Michigan Potato Industry Commission 2007 Michigan Potato Research Report Volume 39 Michigan Potato Industry Commission 13109 Schavey Rd., Ste. 7 DeWitt, MI 48820 517.669.8377 Fax 517.669.1121 www.mipotato.com email: info@mipotato.com March 1, 2008 To All Michigan Potato Growers & Shippers: The Michigan Potato Industry Commission, Michigan State University’s Agricultural Experiment Station and Cooperative Extension Service are pleased to provide you with a copy of the results from the 2007 potato re- search projects. This report includes research projects funded by the Michigan Potato Industry Commission, the USDA Special Grant and special allocations by the Commission. Additionally, the Commission expresses appreciation to sup- pliers of products for research purposes and special grants to the Commission and researchers. Providing research funding and direction to principal investigators at MSU is a function of the Michigan Potato Industry Commission’s Research Committee. Best wishes for a prosperous 2008 season. Greg Iott, Chairman Pat DuRussel, Vice Chairman Duane Andersen Dennis Hanson Carl Kruger Mike Schena Brian Sackett Randy Styma Tim Young Ex Officios: Don Koivisto, MDA Dr. Dave Douches, MSU Table of Contents INTRODUCTION AND ACKNOWLEDGEMENTS 2007 POTATO BREEDING AND GENETICS RESEARCH REPORT David S. Douches, J. Coombs, K. Zarka, D. Berry, D. Kells, and E. Estelle D.S. Douches, J. Coombs, J. Estelle, D. Berry, K. Zarka, C. Long, R. Hammerschmidt and W. Kirk 2007 POTATO VARIETY EVALUATIONS 2007 ON-FARM POTATO VARIETY TRIALS Chris Long, Dr. Dave Douches, Fred Springborn (Montcalm), Dave Glenn (Presque Isle), Dr. Doo-Hong Min and Chris Kapp (Upper Peninsula) RESPONSE OF POTATO TO PHOSPHORUS AND AVAIL. 2007 Darryl Warncke EVALUATION OF CONTROL RELEASE N MATERIALS FOR USE IN POTATO PRODUCTION. 2007 Darryl Warncke WEED CONTROL AND POTATO CROP TOLERANCE Christy Sprague and Gary Powell SEED, IN-FURROW AND EMERGENCE TREATMENTS FOR CONTROL OF SEED- AND SOIL-BORNE RHIZOCTONIA, 2007. W. W. Kirk, R. L. Schafer, P. S. Wharton, P. Tumbalam. IN-FURROW AT PLANTING AND FOLIAR TREATMENTS FOR CONTROL OF COMMON SCAB IN POTATO, 2007 W. W. Kirk, J. Hao, and R. Schafer (PLP). HOST PLANT RESISTANCE AND REDUCED RATES AND FREQUENCIES OF FUNGICIDE APPLICATION TO CONTROL POTATO LATE BLIGHT (2007). W.W. Kirk, P. Tumbalam, R. Schafer, D.S. Douches Page 1 5 26 59 78 81 85 89 91 92 EVALUATION OF FUNGICIDE PROGRAMS FOR POTATO EARLY BLIGHT AND BROWN LEAF SPOT CONTROL, 2007. W. W. Kirk, R. L Schafer, P. Tumbalam and P. Wharton EFFECT OF DIFFERENT GENOTYPES OF PHYTOPHTHORA INFESTANS AND TEMPERATURE ON TUBER DISEASE DEVELOPMENT. William Kirk, Dave Douches, Pavani Tumbalam, Rob Schafer, Joe Coombs and Devan Berry EVALUATION OF FUNGICIDE PROGRAMS FOR POTATO LATE BLIGHT CONTROL: 2007. W. W. Kirk, R. L Schafer, P. Tumbalam, and P. Wharton. W. W. Kirk, R. L Schafer, P. Tumbalam and P. Wharton EVALUATION OF FUNGICIDE PROGRAMS FOR PYTHIUM LEAK CONTROL, 2007. POTATO INSECT BIOLOGY AND MANAGEMENT Edward J. Grafius 2007 POTATO RESEARCH REPORT TO MICHIGAN POTATO INDUSTRY COMMISSION Adam M. Byrne, Walter L. Pett, Beth A. Bishop, and George W. Bird EVALUATION AND COMPARISON OF BIOFUNGICIDES AND FUNGICIDES FOR THE CONTROL OF POST HARVEST POTATO TUBER DISEASES. Kirk, W. W., and Wharton, P. S. SUMMARY REPORT FOR THE 2006-2007 DR. B. F. (BURT) CARGILL POTATO DEMONSTRATION STORAGE Brian Sackett, Chris Long, Dick Crawford, Todd Forbush (Techmark, Inc.), Steve Crooks, Dennis Iott, Keith Tinsey, Tim Young, Jason Walther, Troy Sackett, Randy Styma and Ben Kudwa Page 97 99 104 107 108 129 138 142 2007 MICHIGAN POTATO RESEARCH REPORT C. M. Long, Coordinator INTRODUCTION AND ACKNOWLEDGMENTS The 2007 Potato Research Report contains reports of the many potato research projects conducted by MSU potato researchers at several locations. The 2007 report is the 39th volume, which has been prepared annually since 1969. This volume includes research projects funded by the Potato Special Federal Grant, the Michigan Potato Industry Commission (MPIC), GREEEN and numerous other sources. The principal source of funding for each project has been noted at the beginning of each report. We wish to acknowledge the excellent cooperation of the Michigan potato industry and the MPIC for their continued support of the MSU potato research program. We also want to acknowledge the significant impact that the funds from the Potato Special Federal Grant have had on the scope and magnitude of potato related research in Michigan. Many other contributions to MSU potato research have been made in the form of fertilizers, pesticides, seed, supplies and monetary grants. We also recognize the tremendous cooperation of individual producers who participate in the numerous on-farm projects. It is this dedicated support and cooperation that makes for a productive research program for the betterment of the Michigan potato industry. We further acknowledge the professionalism of the MPIC Research Committee. The Michigan potato industry should be proud of the dedication of this committee and the keen interest they take in determining the needs and direction of Michigan's potato research. Special thanks go to Dick Crawford for the management of the MSU Montcalm Research Farm (MRF) and the many details which are a part of its operation. We also want to recognize Barb Smith and Esther Haviland at MPIC and Greg Steere for helping with the details of this final draft. WEATHER The overall 6-month average maximum temperature during the 2007 growing season was higher than the 6-month average maximum temperature for the 2006 season and was higher than the 15- year average (Table 1). There were eight recorded temperature readings of 90 °F or above in 2007. Two of these days occurred in late July during potato bulking. There were no recorded daytime temperatures above 90 °F or night time temperatures above 70 °F in the month of August. There were no days during the growing season that the air temperature was below 32 °F. There was only one daytime low, below 50 °F, during harvest in mid October. There were three night time lows below 32 °F in October; they occurred on October 13th, 14th and 25th. The average maximum temperatures for June, July and August of 2007 were at or above the 15-year average (Table 1). Rainfall for April through September was 11.77 inches, which was far below the 15-year average. (Table 2). Rainfall recorded during the month of June was the lowest recorded for that month in 15 years. Irrigation at MRF was applied 16 times from June 13th to August 17th , averaging 0.73 inches for each application. The total amount of irrigation water applied during this time period was 11.7 inches. 1 Table 1. The 15-year summary of average maximum and minimum temperatures (°F) during the growing season at the Montcalm Research Farm. April May June July August September 6-Month Average Year Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. 50 1993 50 1994 51 1995 1996 50 48 1997 52 1998 1999 51 50 2000 53 2001 51 2002 2003 49 49 2004 51 2005 2006 51 50 2007 79 75 82 80 73 81 76 79 72 81 82 76 81 80 80 33 34 31 31 31 37 37 34 37 36 33 37 36 36 33 68 66 66 64 59 75 71 70 70 63 64 67 65 61 73 45 43 45 44 39 51 48 49 49 42 44 46 41 46 47 54 57 51 50 54 60 59 56 61 56 56 62 62 62 53 64 73 70 70 69 76 73 70 69 77 72 78 77 68 76 61 60 60 55 57 58 62 56 58 62 58 57 58 61 56 46 51 45 51 50 52 48 49 48 52 48 49 51 48 50 74 78 81 75 79 77 77 75 78 79 77 74 82 78 82 55 55 57 57 56 56 55 57 57 58 52 54 60 54 54 81 79 82 76 80 82 84 77 83 85 81 79 82 83 81 70 71 72 69 69 75 73 71 72 73 72 73 75 72 74 60 55 65 59 55 60 56 57 70 58 58 53 58 58 58 15-Year Average 57 34 67 45 78 56 81 59 78 59 72 49 72 50 The 15-year summary of precipitation (inches per month) recorded during the growing season at the Montcalm Research Farm. Table 2. Year 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 15-Year Average April 3.47 3.84 3.65 2.46 2.02 2.40 5.49 3.18 3.28 2.88 0.70 1.79 0.69 2.73 2.64 2.75 May 3.27 2.63 1.87 3.99 3.13 2.21 5.07 6.46 6.74 4.16 3.44 8.18 1.39 4.45 1.60 3.91 June 4.32 6.04 2.30 6.28 3.54 1.82 5.82 4.50 2.90 3.28 1.85 3.13 3.57 2.18 1.58 3.54 July 2.58 5.16 5.25 3.39 2.80 0.40 4.29 3.79 2.49 3.62 2.60 1.72 3.65 5.55 2.43 3.31 August September 6.40 8.05 4.59 3.69 2.71 2.22 5.46 5.28 5.71 7.12 2.60 1.99 1.85 2.25 2.34 3.56 1.18 1.38 2.96 1.46 3.05 4.03 5.25 4.43 1.59 2.06 0.32 3.90 3.15 1.18 4.15 2.63 Total 23.60 26.90 19.04 22.77 15.66 12.10 30.16 28.46 25.55 22.65 13.25 17.13 15.05 20.31 11.77 21.44 2 GROWING DEGREE DAYS Tables 3 and 4 summarize the cumulative growing degree days (GDD) for 2007. Growing degree days base 50 for May through September, 2007 are in (Table 3) and growing degree days base 40 for May through October, 2007 are in (Table 4). The total GDD base 50 for 2007 was 2495 (Table 3), which is higher than the 10-year average. The total GDD base 40 for 2007 was 4443 (Table 4). Table 3. Growing Degree Days* - Base 50°F. Cumulative Monthly Totals Year 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 10-Year Average May 427 317 313 317 319 330 245 195 283 358 310 June 932 865 780 808 903 762 662 826 765 926 823 July 1545 1573 1301 1441 1646 1302 1200 1449 1444 1494 1440 August September 2180 2070 1851 2079 2214 1922 1639 2035 2016 2084 2616 2401 2256 2379 2613 2256 2060 2458 2271 2495 2009 2381 Table 4. Growing Degree Days* - Base 40°F. Year 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 10-Year Average May 532 639 Cumulative Monthly Totals June 1310 1503 July 2298 2379 August September October 3923 3180 3277 4443 3707 3966 586 1407 2339 3229 3837 4183 *1998-2007 data from the weather station at MSU Montcalm Research Farm (Michigan Automated Weather Network System Entrican, MI.) 3 PREVIOUS CROPS, SOIL TESTS AND FERTILIZERS The general potato research area utilized in 2007 was rented from Steve Comden, directly to the West of the Montcalm Research Farm. This acreage was planted to an alfalfa cover crop in the Spring of 2004 and was harvested for hay for two consecutive seasons. The alfalfa was killed off in the fall of 2006 and the ground was chisel plowed. In the spring of 2007, the recommended rate of potash was applied and disked into the remaining alfalfa residue. The ground was moldboard plowed for direct potato planting. The area was not fumigated prior to potato planting. Potato early die was not an issue in 2007. The soil test analysis for the general crop area was as follows: lbs/A P2O5 K2O Ca Mg pH 5.4 312 (156 ppm) 130 (65 ppm) 650 (325 ppm) 128 (64 ppm) The fertilizers used in the general plot area are as follows. (Variances in fertilizers used for specific research projects are included in the individual project reports.) Application Broadcast at plow down At planting At emergence 1st Early side dress 2nd Late side dress (late varieties) Analysis Rate Nutrients (N-P205-K20) 0-0-60 19-17-0 46-0-0 46-0-0 46-0-0 250 lbs/A 20 gpa 100 lbs/A 100 lbs/A 100 lbs/A 0-0-150 42-37-0 46-0-0 46-0-0 46-0-0 HERBICIDES AND PEST CONTROL Hilling was done in late May, followed by a pre-emergence application of Lorox at 1.5 lb/A and Cinch at 1.33 pints/A. A post-emergence application of Sencor at ¼ lb/A and Matrix at 1 oz/A was made in early July. Platinum was applied at planting at a rate of 8 Fl oz/A. Asanna XL was applied once in late July at 9.6 Fl oz/A. Fungicides used were Bravo, Equus 720 over 12 applications. Potato vines were desiccated with Reglone in early September at a rate of 1 pint/A. 4 Department of Crop and Soil Sciences Michigan State University East Lansing, MI 48824 2007 POTATO BREEDING AND GENETICS RESEARCH REPORT David S. Douches, J. Coombs, K. Zarka, D. Berry, D. Kells, and E. Estelle Cooperators: Ray Hammerschmidt, Ed Grafius Willie Kirk, George Bird, and Chris Long INTRODUCTION At Michigan State University we are breeding potatoes for the chip-processing and tablestock markets. The program is one of four integrated breeding program in the North Central region. At MSU, we conduct a multi-disciplinary program for potato breeding and variety development that integrates traditional and biotechnological approaches. In Michigan, it requires that we primarily develop high yielding round white potatoes with excellent chip-processing from the field and/or storage. We conduct variety trials of advanced selections and field experiments at MSU research locations (Montcalm Research Farm, Lake City Experiment Station, Muck Soils Research Farm and MSU Soils Farm), we ship seed to other states and Canadian provinces for variety trials, and we cooperate with Chris Long on grower trials throughout Michigan. Through conventional crosses in the greenhouse, we develop new genetic combinations in the breeding program, and also screen and identify exotic germplasm that will enhance the varietal breeding efforts. With each cycle of crossing and selection we are seeing directed improvement towards improved varieties (e.g. combining chip-processing, scab resistance and late blight resistance). In addition, our program has been utilizing genetic engineering as a tool to introduce new genes to improve varieties and advanced germplasm for traits such as solids, insect resistance, disease resistance and nutritional enhancement. We feel that these in- house capacities (both conventional and biotechnological) put us in a unique position to respond to and focus on the most promising directions for variety development and effectively integrate the breeding of improved chip-processing and tablestock potatoes. potato industry. Traits of importance include yield potential, disease resistance (scab, late blight, early die and PVY), insect (Colorado potato beetle) resistance, chipping (out-of-the- field, storage, and extended cold storage) and cooking quality, bruise resistance, storability, along with shape, internal quality and appearance. We are also developing potato tuber moth resistant lines as a component of our international research project. If these goals can be met, we will be able to reduce the grower’s reliance on chemical inputs such as insecticides, fungicides and sprout inhibitors, and improve overall agronomic performance with new potato varieties. The breeding goals at MSU are based upon current and future needs of the Michigan Over the years, key infrastructure changes have been established for the breeding program to make sound assessments of the breeding selections moving through the program. These include the establishment and expansion of the scab nursery, the 5 development of the Muck Soils Research Farm for late blight testing, the incorporation of no-choice caged studies for Colorado potato beetle assessment, the Michigan Potato Industry Commission (MPIC)-funded construction of the B.F. (Burt) Cargill Demonstration Storage adjacent to the Montcalm Research Farm, new land at the Lake City Experiment Station along with a well for irrigation and expanded land at the Montcalm Research Farm. Each year, during the winter months, 500-1000 crosses are made using about 150 of PROCEDURE I. Varietal Development the most promising cultivars and advanced breeding lines. The parents are chosen on the basis of yield potential, tuber shape and appearance, chip quality, specific gravity, disease resistance, adaptation, lack of internal and external defects, etc. These seeds are then used as the breeding base for the program. We also obtain seedling tubers or crosses from other breeding programs in the US. The seedlings are grown annually for visual evaluation (size, shape, set, internal defects) at the Montcalm and Lake City Research Farms as part of the first year selection process of this germplasm each fall. Each selection is then evaluated post harvest for specific gravity and chip processing. These selections each represent a potential variety. This system of generating new seedlings is the initial step in an 8-12 year process to develop new varieties. This step is followed by evaluation and selection at the 8- hill, 20-hill and 30-hill stages. The best selections out of the four-year process are then advanced for testing in replicated trials (Preliminary, Adaptation, Dates-of-Harvest, Grower- cooperator trials, North Central Regional Trials, Snack Food Association Trials, and other out-of-state trials) over time and locations. The agronomic evaluation of the advanced breeding lines in the replicated trials is in the annual Potato Variety Evaluation Report. quality russets for the eastern market. Currently the two most desirable potatoes for production and type in Michigan are Russet Norkotah and Silverton Russet. These potatoes suffer as symptomless carriers of PVY. Norkotah also has a weak vine and susceptibility to potato early die. We need a PVY resistant or PVY expressing Silverton Russet potato. We will be making more russet crosses in 2008 to support this new russet market. II. Evaluation of Advanced Selections for Extended Storage we are positioned to evaluate advanced selections from the breeding program for chip- processing over the whole extended storage season (October-June). Tuber samples of our elite chip-processing selections are placed in the demonstration storage facility in October and are sampled monthly to determine their ability to chip-process from colder (42-48°F) and/or 50˚F storage. In addition, Chris Long evaluates the more advanced selections in the 10 cwt box bins and manages the 500 cwt. storage bins which may have MSU-bred lines. III. Germplasm Enhancement "diploid" (2x = 24 chromosomes) breeding program in an effort to simplify the genetic With the Demonstration Storage facility adjacent to the Montcalm Research Farm There is a need to find a russet table potato that will be profitable and produce To supplement the genetic base of the varietal breeding program, we have a 6 system in potato (which normally has 4x chromosomes) and exploit more efficient selection of desirable traits. This added approach to breeding represents a large source of valuable germplasm, which can broaden the genetic base of the cultivated potato. The diploid breeding program germplasm base at MSU is a synthesis of seven species: S. tuberosum (adaptation, tuber appearance), S. raphanifolium (cold chipping), S. phureja (cold-chipping, specific gravity, PVY resistance, self-compatability), S. tarijense and S. berthaultii (tuber appearance, insect resistance, late blight resistance, verticillium wilt resistance), S. microdontum (late blight resistance) and S. chacoense (specific gravity, low sugars, dormancy and leptine-based insect resistance). In general, diploid breeding utilizes haploids (half the chromosomes) from potato varieties, and diploid wild and cultivated tuber-bearing relatives of the potato. Even though these potatoes have only half the chromosomes of the varieties in the U.S., we can cross these potatoes to transfer the desirable genes by conventional crossing methods via 2n pollen. IV. Integration of Genetic Engineering with Potato Breeding Through transgenic approaches we have the opportunity to introduce new genes into our cultivated germplasm that otherwise would not be exploited. It has been used in potato as a tool to improve commercially acceptable cultivars for specific traits. Our laboratory has now 15 years experience in Agrobacterium-mediated transformation to introduce genes into important potato cultivars and advanced breeding lines. We are presently using genes in vector constructs that confer resistance to Colorado potato beetle and potato tuber moth (Bt- cry3A, Bt-cry1Ia1 and avidin), potato tuber moth, late blight resistance via the RB gene, drought resistance (CBF1) and vitamin E. Furthermore, we are investing our efforts in developing new vector constructs that use alternative selectable markers and give us the freedom to operate from an intellectual property rights perspective. In addition, we are exploring transformation techniques that eliminate the need for a selectable marker (antibiotic resistance) from the production of transgenic plants. RESULTS AND DISCUSSION I. Varietal Development Breeding The MSU potato breeding and genetics program is actively producing new germplasm and advanced seedlings that are improved for cold chipping, and resistance to scab, late blight, and Colorado potato beetle. For the 2007 field season, progeny from over 500 crosses were planted and evaluated. Of those, the majority were crosses to select for round whites (chip-processing and tablestock), with the remainder to select for yellow flesh, long/russet types, red-skin, and novelty market classes. In addition to crosses from the MSU breeding program, crosses were planted and evaluated from collaborative germplasm exchange from other breeding programs including North Dakota State University, University of Minnesota, and the USDA/ARS program at the University of Wisconsin as part of the Quad state cooperative effort. During the 2007 harvest, over 1200 selections were made from the 40,000 seedlings produced. All potential chip-processing selections will be tested in January or March 2008 directly out of 40°F and 45°F storages. Atlantic, Pike (50°F chipper) and Snowden (45°F chipper) are chip-processed as check cultivars. Selections have been identified at each stage of the selection process that have desirable agronomic characteristics and chip-processing potential. At the 8-hill and 20-hill evaluation 7 Over 80% of the single hill selections have a chip-processing parent in their Efforts have been made to identify lines with good appearance, low internal defects, state, about 350 and 150 selections were made, respectively. Selection in the early generation stages has been enhanced by the incorporation of the Colorado potato beetle, scab and late blight evaluations of the early generation material. Chip-Processing pedigree. Based upon the pedigrees of the parents we have identified for breeding cold- chipping potato varieties, there is a diverse genetic base. We have at least eight cultivated sources of cold-chipping. Examination of pedigrees shows up to three different cold-chipping germplasm sources have been combined in these selections. Our promising chip-processing lines are MSJ147-1, MSJ036-A (scab resistant), MSH228-6 (moderate scab resistance), MSJ126-9Y (moderate scab resistance), MSJ316-A (moderate scab resistance), MSK061-4 (moderate scab resistance), MSK409-1 (scab resistant), MSN238-A (scab resistance), MSL007-B (scab resistance), MSM246-B, MSN191-2Y, MSL292-A, MSR061-1 (scab and PVY resistant) and MSQ070-1 (scab and late blight resistant). Other promising lines include MSQ089-1 (scab resistant), MSQ492-2 (scab and late blight resistant), MSP516-A (scab and late blight resistant), MSR036-5 (scab and late blight resistant), MSR102-3 (scab and late blight resistant), MSR127-2 (scab resistant), MSR041-5 (scab and late blight resistant) and MSR160-2Y (PVY, scab and late blight resistant). Tablestock good cooking quality, high marketable yield and resistance to scab and late blight. Our current tablestock development goals now are to continue to improve the frequency of scab resistant lines, incorporate resistance to late blight along with marketable maturity and excellent tuber quality, and select more russet and yellow-fleshed lines. Potato lines with We have also been spinning off some pigmented skin and tuber flesh lines that may fit some specialty markets. From our breeding efforts we have identified mostly round white lines, but we also have a number of yellow-fleshed and red-skinned lines, as well as long, russet type and purple skin selections that carry many of the characteristics mentioned above. We are also selecting for a dual-purpose russet, round white, red-skin, and improved Yukon Gold-type yellow-fleshed potatoes. Some of the tablestock lines were tested in on-farm trials in 2007, while others were tested under replicated conditions at the Montcalm Research Farm. Promising tablestock lines include MSI005-20Y, MSN105-1 and MSM171-A. We have a number of tablestock selections with late blight resistance. These are MSL072-C and MSM171-A. MSL211-3 and MSN105-1 has late blight and scab resistance. MSA8254-2BRUS is a russet table selection that has scab resistance, while MSL794-BRUS has late blight resistance. Some newer lines with promise include MSQ176-5 (late blight resistant), MSN230-6RY (scab and late blight resistant), MSM182-1 (PVY and late blight resistant), MSQ440-2 (scab and late blight resistant and MSL268-D (late blight resistant). MSM288-2Y is a yellow flesh selection with scab resistance. Some new pigmented lines are MSS582-1 (purple splash) and Michigan Red and Purple Splash. MSQ558-2RR is a red fleshed chipper and MSQ432-2PP is a purple-fleshed chipper. MSL228-1 (purple splash) is being considered by Gurney’s Seed for their home garden catalog (Garden’s Alive). 8 Disease and Insect Resistance Breeding Scab: Disease screening for scab has been an on-going process since 1988. Results from the 2007 MSU scab nursery indicate that 62 of 166 lines evaluated had a scab rating of 1.4 or less (better or equivalent to Pike). The limitation of breeding for scab resistance is the reliance on the scab nursery. We found a moderate correlation between the field screening and greenhouse screening for scab. We expanded the scab nursery with an additional acre of land nearby. This expansion has allowed us to conduct early generation selection for scab resistance among our breeding material. In 2007, 90 of 279 early generation selections showed strong scab resistance. These data were incorporated into the early generation evaluation process at Lake City. We are seeing that this expanded effort is leading to more scab resistant lines advancing through the breeding program. Late Blight: With support from GREEEN, the Muck Soils Research Farm, Bath, Michigan has become an excellent North American site for late blight testing because of the humid microclimate and isolation from major commercial potato production. As a result, late blight infection has been consistently achieved each year making breeding efforts to select late blight resistant germplasm very efficient. In 2007 41 of 160 advanced breeding lines were classified as late blight resistant. Of the early generation material tested 49 of 190 lines were late blight resistant. Colorado potato beetle: With support from GREEEN, we also introduced an early generation Colorado potato beetle screen at the Montcalm Research Farm. In 2007, 10 of 69 breeding lines were at least moderately resistant to Colorado potato beetle at the Montcalm Research Farm Beetle Nursery. The beetle pressure was extremely high leading to complete defoliation in all susceptible check lines. Percent defoliation was visually estimated during the beetle infestation in June and July. This resistant material was selected for further advancement in the breeding program and also for use in the next round of crossing to develop beetle resistant cultivars. Some of these lines are beginning to enter the preliminary trials in the breeding program. Concurrently, a field cage (no- choice) experiment was conducted to evaluate 3 avidin transgenic lines. In 2007 beetle behavior and defoliation was evaluated in lines that expressed differing levels of avidin. The data from this experiment has not been analyzed yet. It is a great challenge to achieve host plant resistance to insects in a commercially acceptable line. We have some promising advanced selections with partial resistance to Colorado potato beetle. In addition, we have Bt-cry3A transgenic lines that could be commercialized if the processors renewed their acceptance and regulatory environment was modified to reduce costs. I am on a national committee to help build infrastructure to so that transgenic specialty crops like potato can be deregulated in a more efficient and less costly manner. However, the national potato industry needs to be supportive of this technology before we can move forward. 9 II. Sugar Profile Analysis of Early Generation Selections for Extended Storage: Chip- processing Results From the MPIC Demonstration Commercial Storage (October 2006 - June 2007) The MSU Potato Breeding Program has been conducting chip-processing evaluations each year on potato lines from the MSU breeding program and from other states. For 8 years we have been conducting a long-term storage study to evaluate advanced breeding lines with chip-processing potential in the Dr. B. F. (Burt) Cargill Potato Demonstration Storage facility directly adjacent to the MSU Montcalm Research Farm to identify extended storage chippers. We evaluated advanced selections from the MSU, Wisconsin and North Dakota breeding programs for chip-processing over the whole extended storage season (October-June). Tuber samples of our elite chip-processing selections were placed in the demonstration storage facility in October and were sampled 6 times to determine their ability to chip-process from storage. In October 2006, tuber samples from 12 MSU lines, 1 North Dakota line, and four Wisconsin lines from the Montcalm Research Farm and Lake City Experiment Station trials were placed in the bins. The first samples were sugar-profiled and chip-processed at TechMark in November and then five more times until June 4, 2007. Samples were evaluated for chip- processing color, defects and glucose and sucrose were measured. Because of the extremely high sugar levels of some samples in November and December, 5 lines were dropped from the sugar profiling study. These high sugar levels were attributed to the poor fall harvest conditions and will be retested in 2007-8. Table 1 summarizes the chip-processing color and scab rating of 12 lines over the 7-month storage season. From November to April all lines chip-processed acceptably with a 1.0 color score. This is not surprising since the best chip-processing lines were selected for this study. In some cases, SED or hollow heart was observed in a few chips, but no patterns emerged. In June the color darkened for 9 of the 12 lines and the storage test was terminated. Based upon the data, many of these lines have potential to be further tested in storage tests. Six lines had a good combination of color, low defects and desirable sugar profiles. Figure 1 shows the TechMark sugar profiles of sucrose, glucose and undesirable color for three MSU lines (MSL007-B, MSM246-B and MSN191-2Y) that performed well in the study. MSL007-B has scab resistance. These and other lines will be tested further in 2007-8. 10 Table 1. 2006-2007 Early Generation Sugar Profiling Study SFA Chip Scores for seven months storage at the MPIC Demonstration Storage Male NY88 Line Female MSJ461-1LBR Tollocan MSA105-1 MSG227-2 MSL007-B MSI111-A MSG227-2 MSM102-A MSE274-A NY115 MSM246-B MSN099-B MSG015-C MSI111-A MSN191-2Y MSI234-6Y MSH098-2 MSF015-1 MSJ212-2 MSP292-7 ND5775-3 unknown unknown RHL167 Snowden W2133-1 unknown unknown W2310-3 W2324-1 Snowden RHL166 unknown unknown W2717-5 Average 11/6/06 12/4/06 1/15/07 2/26/07 4/11/07 6/4/07 Date 1.0 1.0 1.5 1.0 1.0 1.5 1.0 1.0 1.0 1.0 1.0 1.0 1.1 1.0 1.0 1.0 1.0 1.0 1.5 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.5 1.0 1.0 1.0 1.0 1.0 1.5 1.5 2.5 1.5 2.5 1.5 2.0 1.5 1.0 1.0 1.5 1.0 1.6 2006 Scab 1.8 0.8 1.5 2.5 1.3 2.5 1.8 2.0 2.0 1.8 2.6 2.5 1.9 *Note: These five lines were chipped at MSU beginning 1/15/07 SFA Chip Score 1-5 scale: 1=excellent; 5=poor (>= 2.5 is considered unacceptable). Scab Rating: 0: No Infection; 1: Low Infection <5%; 3: Intermediate; 5: Highly Susceptible. 11 B - 7 0 0 L S M B - 6 4 2 M S M Y 2 - 1 9 1 N S M 12 In 2007, only a few diploid populations were evaluated as single hills. From this III. Germplasm Enhancement breeding cycle, we plan to screen the selections chip-processing from storage. In addition, selections were made from over progeny that was obtained from the USDA/ARS at the University of Wisconsin. These families represent material from South American potato species and other countries around the world that are potential sources of resistance to Colorado potato beetle, late blight, potato early die, and ability to cold-chip process. Through GREEEN funding, we were able to initiate a breeding effort to introgress leptine- based insect resistance. From previous research we determined that the leptine-based resistance is effective against Colorado potato beetle. We will continue conducting extensive field screening for resistance to Colorado potato beetle at the Montcalm Research Farm and in cages at the Michigan State University Horticulture Farm in 2008. In 2004 we made crosses with late blight resistant diploid lines derived from Solanum microdontum to our tetraploid lines. This S. microdontum-based resistance is unique and very effective against the US-8 strains. These progeny are being grown in the greenhouse and now we have used DNA marker analysis to identify which lines have the late blight resistance. We have conducted lab-based detached leaf bioassays and have identified resistant lines. We will field test these in 2008. IV. Integration of Genetic Engineering with Potato Breeding Segregation of Transgenes and Selectable Markers in Tetraploid Potato Crosses The insertion of transgenes into cultivated potato offers the opportunity to introduce novel genes/traits into the cultivated germplasm. If a transgenic event is commercialized in the US, the progeny generated from the transgenic lines are also approved for growing. Thus, transgenic lines can be valuable parents in a breeding program. We have generated transgenic lines and made crosses to examine segregation of transgenes and the nptII selectable marker. In one set of crosses we examined the segregation of the Bt-cry1Ia1 gene and the nptII gene. We also tested a subset of the progeny for potato tuber moth resistance. We learned that the Bt gene is inherited in a simple genetic manner and all the progeny that carried the Bt gene were resistant. In another set of crosses we examined the segregation of the RB gene and the nptII genes. In some of these crosses the RB gene was co-integrated with the nptII gene in the transgenic line. In another transgenic line the RB gene was independently integrated from the nptII gene so that RB and nptII would segregate independently in the progeny. Segregation data showed that we were able to select progeny that carried the RB gene, but not the nptII gene. Hence the progeny do not have the antibiotic resistance gene. Separating out the nptII gene makes transgenic potatoes have greater public perception. In addition, we have been able to combine the RB gene for late blight resistance with the conventionally bred resistance genes. We will further test these progeny in 2008. Commercialization of Potato Tuberworm Resistant Potatoes in South Africa The potato tuberworm (Phthorimaea operculella Zeller) is a primary pest problem facing potato farmers in developing countries. Currently, the primary means to control the potato 13 tuberworm and avoid major crop losses is the use of chemical pesticides. Michigan State University (MSU), funded by the U.S. Agency for International Development (USAID), initiated biotechnology research on the development of potato tuberworm resistant varieties in 1992. A Bacillus thuringiensis (Bt)-cry1Ia1 gene, was successfully introduced into several potato varieties and shown to be highly resistant to potato tuberworm in the Spunta-G2 line (both tuber and foliage). This Bt potato will be one of the first public sector developed products to reach farmers in developing countries and will serve as a model for the public sector deployment of insect resistant transgenic crops. The commercialization project includes six components: Product Development, Regulatory File Development, Obtaining Freedom to Operate and Establishing Licensing Relationships, Marketing and Technology Delivery, Documentation of Socio-Economic Benefits, and Public Communication. This technology would also have benefits in controlling PTM in the US and reducing the need for insectcide-based protection. In 2007 we focused on collecting the regulatory data that has to be submitted to the review agency. We also evaluated 15 Bt-progeny in replicated trials at the Montcalm Research Farm. All these lines are potato tuber moth resistant and many are also late blight resistant. Based upon the agronomic data this year, we have reduced the number of progeny to further advance to 7. V. Variety Release We are planning to release MSJ036-A as Kalkaska in 2008. We are continuing to promote the seed production and testing of Beacon Chipper, a 2005 release. In addition, we are continuing to promote Michigan Purple, Jacqueline Lee for the tablestock markets. Boulder is being commercially grown in Quebec. Commercial seed production has been initiated for MSN105-1, a round white potato for the tablestock market. Lastly, commercial seed of MSH228-6, MSJ147-1, MSK061-4 and MSJ126-9Y are being produced and we will continue to seek commercial testing of these lines. We have also initiated a focused ribavirin-based virus eradication system to generate virus-free tissue culture lines for the industry. Thirty lines are in ribaviran treatment at this time to remove PVS and PVY from lines. This year 74 new breeding lines are being put into tissue culture. MSU Variety releases Michigan Purple Parentage: W870 x Maris Piper Developers: Michigan State University and the Michigan Agricultural Experiment Station Plant Variety Protection: Yes Strengths: Michigan Purple is a purple-skinned tablestock variety with brilliant white flesh with low incidence of internal defects. The tubers have an attractive round-ovoid shape and a strong iridescent purple skin. Yield is high under irrigated conditions, and also performs well under dryland conditions. Weaknesses: Susceptibility to common scab. 14 Incentives for production: The purple-skinned, white-fleshed tubers of Michigan Purple offer a unique type that could lend itself to the specialty variety market, such as gourmet restaurants and food stores, as well as farm and road-side markets. MSJ036-A Parentage: B1254-1 X S440 Developers: Michigan State University and the Michigan Agricultural Experiment Station. Plant Variety Protection: In preparation Strengths: MSJ036-A is a high yielding, round white potato with an attractive round appearance with shallow eyes.MSJ036-A has a strong vine and a full season maturity. This variety has resistance to Streptomyces scabies (common scab) stronger than Pike. MSJ036-A also has chip-processing storage characteristics and better tolerance to blackspot bruise than Snowden. Weaknesses: Sugar levels have to be watched at harvest during cold temperatures. Incentives for production: High yield and good tuber type combined with scab resistance. MSJ147-1 15 Parentage: NorValley X S440 Developers: Michigan State University and the Michigan Agricultural Experiment Station Plant Variety Protection: Will be considered. Strengths: MSJ147-1 is a round white chip-processing potato that has a bright skin, white flesh and round shape. In addition, it has been determined to store at temperatures below 50F and maintain low reducing sugar levels into May or June. Weaknesses: Small vine, slow to emerge. Incentives for production: MSJ147-1 produces many A-size tubers that are low in defects. Potatoes maintain low reducing sugar content for chip-processing out of the field and from storage. MSJ461-1 Parentage: Tollocan X NY88 Developers: Michigan State University and the Michigan Agricultural Experiment Station, Michigan Potato Industry Commission Plant Variety Protection: Plant Variety Protection is being considered for this variety. Strengths: MSJ461-1 is a round white chip-processing variety with an attractive round shape and bright skin. The primary strength of this variety is its strong foliar resistance to late blight (Phytophthora infestans) combined with chip-processing quality. MSJ461- 1 can also be marketed as tablestock because of its good culinary quality. The tubers will chip process out-of-the-field and from 10°C (50°F) storage. MSJ461-1 performed well in Michigan on-farm trials and regional testing. Under irrigated conditions, the yield is similar to Snowden. MSJ461-1 is being considered for release, although no name has yet been chosen for this line. Weaknesses: The specific gravity of MSJ461-1 is lower than Snowden in Michigan. 16 Incentives for production: High yield with uniform tuber size combined with strong foliar resistance to late blight, GN resistance and tolerance to verticillium wilt. Can be used for both chip-processing and table use. Jacqueline Lee (MSG274-3) Parentage: Tollocan x Chaleur Developers: Michigan State University and the Michigan Agricultural Experiment Station Plant Variety Protection: Yes Strengths: Jacqueline Lee has a bright golden skin, yellow flesh, attractive oval shape and excellent cooking qualities that make it suitable for tablestock use. In addition, it has been determined to have a high level of foliar resistance to the US-8 genotype of Phytophthora infestans under Michigan field and greenhouse conditions. Weaknesses: Susceptibility to common scab. Incentives for production: The tubers have an attractive tuber type, with bright and smooth skin and a yellow flesh, typical of many European varieties. The plants yield a heavy set of medium-sized (3-6 oz.), uniform tubers. The foliage has a high level of resistance to the US-8 genotype of Phytophthora infestans. These medium-sized, uniform, oval-shaped tubers of Jacqueline Lee offer a unique type that could lend itself to the specialty variety market, such as farm and road-side markets. 17 Boulder (MSF373-8) Parentage: MS702-80 x NY88 Developers: Michigan State University and the Michigan Agricultural Experiment Station Plant Variety Protection: In application Strengths: Boulder is a round white selection with medium specific gravity that can be used in both the tablestock and chip-processing markets. The tubers of Boulder are large in size with a low incidence of internal defects. Boulder yields well under both irrigated and dryland conditions. Weaknesses: Over-size tubers may have deep eyes similar to Red Pontiac. Incentives for production: High percentage of A-size tubers and excellent culinary quality. 18 Map-based cloning of a Major Late Blight Resistant QTL in Solanum microdontum (GREEEN Project) Problem Statement: Potato (Solanum tuberosum L.) is the fourth most important food crop in the world and the top vegetable crop is the United States. In Michigan the potato is approximately $120 million value crop of which the majority is processed as chips, making Michigan the premier state for supplying this market. Late blight caused by Phytophthora infestans (Mont.) de Bary is a significant constraint to potato production in the US and worldwide. One of the major goals of our potato breeding program is to introduce new market-quality cultivars with late blight resistance. Quantitative trait loci analysis (QTL) of a diploid mapping population identified closely linked markers associated with foliar resistance to late blight that explained about 70% of the disease reaction (Bisognin et al. 2004) and is resistant to all Michigan P. infestans isolates. Based upon the pedigree and resistance reaction of the S. microdontum germplasm, the resistance in this material is a unique and it needs to be utilized and combined with other late blight resistance genes. Recently other late blight resistance genes have been mapped and cloned from S. bulbocastanum (Song et al. 2003; van der Vossen et al. 2003), S. mochiquense (Smilde et al. 2004), and a complex genomic hybrid (Park et al. 2005). The resistance genes from these Solanum species offers race non-specific resistance unlike those previously utilized from S. demissum. Access to specific resistance genes combined with the ability to pyramid transgenes is a powerful strategy to study the interaction of P. infestans and host plant resistance and breed cultivars with durable host plant resistance. The purpose of this research is to initiate the map-based cloning of a major late blight QTL from S. microdontum. unique opportunity to pyramid late blight resistance genes in an analytic manner. In this way we could study the interaction of P. infestans and single and combined gene-based host plant resistance. Moreover, the pyramided resistance genes in a single genotype should be a better strategy to deploy late blight resistant potato varieties (Dangl and Jones 2001). Objectives: 1. The ability to transform major late blight resistance genes into potato provides a Construct a high resolution map of the late blight QTL region in S. microdontum to identify tightly linked flanking markers. Create a BAC library from S. microdontum. Conduct late blight assessment of mapping population. 2. 3. Accomplishments: 1. Construct a high resolution map of the late blight QTL region in S. microdontum to identify tightly linked flanking markers. A mapping population, based upon SSRs and AFLPs, was established between a late blight resistant S. microdontum selection (TF75-5) and a susceptible diploid clone (MSA133-57). SSR marker, STM0020, was identified to be tightly linked to a major 19 QTL affecting late blight resistance (Bisognin et al. 2004). We currently have 5 markers (including STM0020) linked to the late blight resistance QTL. The genetic marker STM0020 was placed on Chr. 4. A second marker, STM1002 (aka. S9101 and X67511), had earlier been placed in the same linkage group as STM0020 and it too has since been mapped to Chr.4, thus confirming the placement of our QTL on Chr. 4. Since that time, over 40 Chr. 4 specific markers (Table 1) have been screened using a subset of a mapping population to identify polymorphisms between late blight resistant and sensitive individuals. To date, none of these markers has resulted in a difference that allowed distinct identification of the resistance phenotype. Additional markers will need to be tested in order to develop a high resolution map of the region surrounding the late blight QTL. With this QTL being located on Chr. 4, it may be associated with the R-gene hotspot that already includes R2, R2-like and Rpi-blb3 genes for late blight resistance. An alternative PCR based approach for isolating resistance genes analogs (RGAs) has also begun. This approach uses conserved regions found in most of the cloned R genes to design primers which are then used to amplify RGAs from genomic DNA. This approach has been used by others to map resistance genes in a number of different plants. In our situation, if any RGAs are found that map to Chr. 4, they will be considered candidates genes from which additional markers can be generated. To date, this protocol has yielded a few classes of amplification products (Fig. 1) which will be sequenced and subsequently compared to databases to confirm they contain putative RGA DNA. 2. Conduct late blight assessment of mapping population. The greenhouse grown mapping population was subjected to detached leaf assays with three replications. Fully expanded and healthy leaflets were collected and placed in Petri dishes in which high moisture is maintained. Each leaflet was sprayed with a suspension of P. infestans US-8 isolate (Pi02-007, the most aggressive isolate). The leaflets will be evaluated for percent infection at 6, 9 and 12 days according to Kuhl et al. (2001). Based upon the 12 day percent infection the population had a continuous distribution for reaction to late blight. Some progeny were more resistant than the original S. microdontum source of resistance (TF75-5). This mapping population will be useful for fine-mapping studies 3. Create a BAC library from S. microdontum Clemson University Genomics Institute (CUGI) was chosen to produce a BAC library because of their extensive experience in creating custom large insert BAC libraries with an average insert size generally ranging between 120 and 160kb. CUGI has produced numerous plant, animal and microbial BAC libraries encompassing many different taxa in the tree of life. The S. microdontum BAC library was constructed using HindIII digested genomic DNA. Greater than 36,000 colonies/clones were picked, each containing inserts of at least 120kb of sequence which in total represents about 5 times coverage of the entire genome. The library was completed in June 2007 and we have plates containing each individual clone as well as arrayed filters for screening. 20 Impacts: We are making forward progress in cloning a putative R-gene from S. microdontum for late blight resistance. The ability to transform major late blight resistance genes into potato provides a unique opportunity to pyramid late blight resistance genes in an analytic manner. In this way we will be able to study the interaction of P. infestans and single and combined gene-based host plant resistance and extend our knowledge of fundamental host-pathogen interactions. Moreover, the pyramided resistance genes in a single genotype should be a more durable strategy to deploy late blight resistant potato varieties (i.e., should be more difficult to overcome multiple new R genes than one R gene at a time). The use of late blight resistant varieties will lessen the need for weekly protectant fungicides programs. As a result, production costs can be lowered and environmental impact of the fungicides will be lessened. Photos, charts, graphs: SCAR Markers Table 1. Screened Markers CAPS SSR Others Markers Markers E35M54.G TG506R STM0020 Th21 E32M48.b TGH2 STM1002 TG339 STM3016 CT229 cLPT5B19 E35R50.a STM5112 At4g09010 AF411807L E32M61.b STM5140 At3g16150 RGH3 STM5156 At1g42990 TG370F STG008 At1g76080 B57R 54I8L STG018 Blb22T 139K15L rpiblb3-1 STG020 STI001 rpiblb3-2 B10L Blb22S rpiblb3-3 STI012 Blb25S STI020 STI026 Blb25T STI055 GP511 GP180-a LITERATURE CITED Figure 1. Restriction Digest of Putative RGA DNA. PCR amplified DNA using degenerate primers was cloned into pGEM T-Easy (Promega), transformed into E.coli, cultures grown and plasmid isolated. The plasmid was digested with RsaI and run on a 1% agarose gel. Lane M is a 100bp DNA marker. Lanes 1-1 through 1-9 and 2-1 through 2-9 represent individual clones originating from different sets of primer pairs respectively. X is an empty lane. This image shows at least four distinct classes of insert DNA based on banding pattern. Lanes 2-3 through 2-7 insert DNA was not cut by RsaI. Bisognin, D.A. D.S. Douches, L. Buszka, G. Bryan and D. Wang. 2004. Mapping late blight resistance in Solanum microdontum Bitter. Crop Science 45: 340-345. Dangl, J.L. and J.D. Jones. 2001. Plant pathogens and integrated defence responses to infection. Nature 411:826-833. Kuhl, J.C., Hanneman, R.E. Jr. and Havey, M.J. 2001. Characterization and mapping of Rpi1, a late blight resistance locus from diploid (1EBN) Mexican Solanum pinnatisectum. Mol. Genet. Genom. 265: 977-985. 21 mochiquense chromosome IX carries a novel late blight resistance gene Rpi- moc1. Theor. Appl. Genet. 110:252-258. Song, J. Bradeen, J.M., Naess, S.K., Raasch, J.A., Wieglus, S.M., Haberlach, G.T., Lui, J., Kuang, H., Austin-Phillips, S., Buell, C.R., Helgeson, J.P. and Jiang, J. 2003. Gene RB cloned from Solanum bulbocastanum confers broad spectrum resistance to potato late blight. Proc. Nat. Acad. Sci. 100:9128-9133. van der Vossen, E.A., Sikkema, A., Hekkert, B.T.L., Gros., J. Stevens, P., Muskens, M. Wouters, D., Pereira, A., Stiekema, W.J., and Allefs, S. 2003. An ancient R gene from the wild species Solanum bulbocastanum confers broad-spectrum resistance to Phytophthora infestans in cultivated potato and tomato. Plant J. 36: 867-882. Park, T.H., Vleeshouwers, V.G.A.A., Hutten, C.B., van Eck, H.J., van der Vossen, E., Jacobsen, E. and Visser, R.G.F. 2005. High-resolution mapping and anlaysis of the resistance locus Rpi-abpt against Phytophthora infestans in potato. Mol. Breed. 16:33-43. Smilde, W. D., Brigneti, G., Jagger, L., Perkins, S. and Jones, J.D.G. 2004. Solanum 22 What has that Potato Breeding Program been doing? This year marks a time of 20 years at Michigan State University and I have been continuously involved in potato breeding and genetics research for 25 years. This spring will begin the 20th year of the breeding program since I made my first crosses in Michigan and it seemed like a time for reflection. I fondly remember meeting with Dick Chase, Ben Kudwa and a few growers during the interview process and learning what the industry needs. There was a need for a better storage chipper than Atlantic and varieties with improved internal quality, scab resistance, bruise resistance and with high specific gravity. Potato early die was also a concern. In the table market there was a need for a better Yukon Gold and Onaway market type. With an emphasis on round white potatoes, I set off to work towards these objectives. Ray Hammerschmidt and I teamed up on the scab resistance efforts and with George Bird on the potato early die research. I learned that the genetics of scab resistance is not well understood and characterizing scab resistance has a strong environmental interaction. There were also few lines that had scab resistance that were not russets. I these first four years we were trying to learn what parents could transfer the desired traits we needed. During that time we made and evaluated a few thousand crosses and this helped focus further crossing schemes to improve our chances of finding desirable varieties. Early on there was a common pattern: if the scab resistance was in a line, the chip quality was usually poor. The reverse was also common. Combining scab resistance with chip-processing quality was a challenge. We also had to establish a tissue culture lab so for line maintenance and for providing the industry with plantlets in seed increase. Today we are now using ribaviran to remove virus from the advanced breeding lines that are brought into tissue culture. In 1992 we moved the breeding program to Lake City where we had better disease and insect isolation. This helped reduce the leaf roll and PVY infection. Also Colorado potato beetle was developing resistance and we began looking into Bt genes and natural resistance from the wild species as a long-term effort to breed beetle resistant potatoes. We established research collaborations with Ed Grafius and Walter Pett. Through USAID we were able obtain funding to use genetic engineering techniques to introduce genes for insect resistance. This line of funding continues through 2008. In the second four years, Dr. Kaz Jastrzebski joined us from Poland and we identified many lines with excellent chip quality from storage. During this period we created the foundation for the chip processing quality in our breeding material. Scab resistance was elusive. We learned that the scab evaluation trials in the scab nursery required multiple years to confidently identify resistant lines, whereas other traits were more quickly characterized. Then in the mid-1990s came the re-emergence of late blight, but it was a more aggressive strain than what was observed in the past. All breeding programs across North America began to add late blight resistance to the breeding objectives. There was a lucky convergence in Michigan. Willie Kirk joined MSU and the Muck Soils Research Farm 23 was the best site in the US for testing for late blight resistance. Adding late blight resistance to our breeding objectives created new challenges. Identifying resistance and learning the breeding value of the resistance sources required extra effort and also led to another set of observations. The late blight resistant sources were very late maturing, scab susceptible and poor chippers. It was a challenge to combine chip-processing quality, scab resistance and late blight resistance. With the Muck Soils Farm Research farm being such a reliable late blight testing site. We proposed that that we could use early generation selection for late blight resistance. This effort increased our breeding efficiency. We were able to select numerous late blight resistant lines and began to find lines that combined chip-processing or scab resistance with late blight resistance. Comparing our breeding progress in late blight resistance to our progress in scab resistance, scab resistance breeding was not as efficient. We attributed this to the difficulty of accurately identifying resistant lines. We made the decision to expand the scab nursery, create higher levels of scab infection in the soil and attempt early generation selection. It took us five years to create a new scab nursery with high infection levels on the MSU campus and we then began to expand our scab evaluation to early generation selections in the breeding program. We now screen all our early generation selections (8, 20, 30 and 50-hill selections) for late blight resistance, scab resistance, specific gravity and chip processing each year and incorporate this data into the selection process in the field. We also have established a Colorado potato beetle nursery at the Montcalm Research Farm for screening the breeding material that has been bred for insect resistance. In the lab we use DNA analysis to identify the Golden Nematode and PVY resistant lines. Advanced breeding lines are evaluated for all these traits above along with vine maturity, blackspot bruise resistance, yield, internal defects and chip-processing from storage. Select lines are screened in the potato early die trial at Montcalm and advanced chip-processing lines are evaluated in the Demonstration Storage. Chris Long takes the promising lines from the program and moves them through on-farm trials that complement the data from the Montcalm Research Farm. The most promising chip-processing lines for commercialization are tested in the 10 and 500 cwt bins and also sugar profiled. Along side the development of the breeding program in the past two decades, there has been the concurrent development of the commercial seed production of MSU lines, commercial testing, construction of the Demonstration storage building, variety release mechanisms, plant variety protection, licensing of the varieties and determination of royalty structure. These steps, despite not being research oriented are critical to the successful commercialization and release of an MSU variety. In 2007 we have two MSU lines in the Demonstration storage bins. We see MSJ036-A (Kalkaska), a cross from 1997, being released by MSU and commercialized. It is a scab resistant chipper. We have a series of other scab resistant chipping lines that will be evaluated on commercial scale in the future (MSH228-6, MSK061-4, MSJ126-9Y and MSK409-1). Interestingly, the scab resistance in these chippers comes from different sources. This gives us the opportunity to make improvements in scab resistance. 24 Moreover, the pedigrees also indicate that chip-processing (low sugars) in these lines are from different sources. So we also have the ability to make further genetic improvements in chipping. Also in the storage is MSJ147-1. This line is an excellent long term storage chipper that can process from colder storage temperatures. If you study the pedigree you will see that multiple sources of chip-processing quality including two wild species from South America. On the female side ND860-2 (cold chipper derived from S. phureja) is crossed to Norchip. On the male side the cold chipping is introduced from S440 which has S. tarijense as a unique cold chipping source. A line that has been very important in our breeding program is MSJ461-1. This round white potato has high yield, uniform round white potatoes with low incidence of internal defects, strong late blight resistance, Golden nematode resistance along with Verticillium wilt resistance. It has become an important parent to combine with our scab resistant chipping potatoes. We are now a number of ‘next generation’ advanced breeding lines that combine late blight and scab resistance with chip -processing. One clone, MSQ070- 1, is being sugar profiled this storage season. With a desirable sugar profile, we will consider fast tracking this line. Three of the ‘next generation’ lines also are PVY resistant and many are Golden nematode resistant. We are very excited about the future! When I look at the breeding material and varieties in our program up to this time, we have an excellent genetic base. We have incorporated 15 different sources of scab resistance into our advanced lines and varieties, 9 sources of late blight resistance and 20 sources of chip-processing. We have also broadened the genetic base by using 6 different wild potato species to bring in traits such as scab resistance, late blight resistance, chip- processing from cold storage, PVY resistance, Verticillium wilt resistance, high specific gravity and Colorado potato beetle resistance. With this material we will be able to continue to make genetic improvements. When we combine this with our genetic engineering efforts, we are in for an exciting next 20 years! Lastly, for all this to work, the human capital is very important. The MSU breeding and genetics program will not work without the great work of Joe Coombs, Kelly Zarka, Jay Estelle, Devan Berry, Donna Kells, Dick Crawford (at Montcalm Research Farm) and many of the past technical staff over the years. In the industry, having great cooperators in the seed industry (Jeff Axford, Kruegers, Sklarzycks, Iotts), commercial growers (Sandyland, Lennards, Walthers, Sackett Potatoes, Sackett Acres, Crooks, Leep) have been valuable in moving the MSU advanced selections through the breeding program and along the commercialization path. I feel much honored to be hired by Michigan State University to run the potato breeding and genetics program. The opportunity to run my own potato breeding program and release varieties important to the industry is an ideal career and I am still working hard to achieve my goal of breeding improved varieties. 25 Departments of Crop and Soil Sciences and Plant Pathology Michigan State University East Lansing, MI 48824 Each year, the MSU potato breeding and genetics team conducts a series of INTRODUCTION variety trials to assess advanced potato selections from the Michigan State University and other potato breeding programs at the Montcalm Research Farm (Entrican). In 2007, we trialed 193 varieties and breeding lines. The variety evaluation also includes disease testing in the scab nursery (MSU Soils Farm, E. Lansing) and foliar and tuber late blight evaluation (Muck Soils Research Farm, Bath). The objectives of the evaluations are to identify superior varieties for fresh market or for processing, and to develop recommendations for the growing of those varieties. The varieties were compared in groups according to market class, tuber type, skin color, and to the advancement in selection. Each season, total and marketable yields, specific gravity, tuber appearance, incidence of external and internal defects, chip color (from field, 45°F and 50°F storage), as well as susceptibilities to common scab, late blight (foliar and tuber), and blackspot bruising are determined. PROCEDURE Entrican, MI. They were planted as randomized complete block designs with two to four replications. The plots were 23 feet long and spacing between plants was 12 inches. Inter-row spacing was 34 inches. Supplemental irrigation was applied as needed. The field experiments were conducted on new potato ground that was in corn the previous year. dates to evaluate early and late harvest potential (Date-of-Harvest trial: Early and Late). The other field trials were the Round White, Russet and Long-Types, Red-Skinned, Adaptation (chip-processors and tablestock), and Preliminary (chip-processors and tablestock) and Transgenic. In each of these trials, the yield was graded into four size classes, incidence of external and internal defects in > 3.25 in. diameter (or 10 oz. for Russet types) potatoes were recorded, and samples for specific gravity, chipping, disease tests, bruising, and cooking tests were taken. Chip quality was assessed on 25-tuber The most advanced selections in the breeding program were harvested at two Ten field experiments were conducted at the Montcalm Research Farm in Funding: Fed. Grant/MPIC 2007 POTATO VARIETY EVALUATIONS D.S. Douches, J. Coombs, J. Estelle, D. Berry, K. Zarka, C. Long, R. Hammerschmidt and W. Kirk 26 samples, taking two slices from each tuber. Chips were fried at 365°F. The chip color was measured visually with the SFA 1-5 color chart. Tuber samples were also stored at 45°F and 50°F for chip-processing out of storage in January and March. Advanced selections are also placed in the Commercial Demonstration Storage for monthly sampling. The scab nursery at the MSU Soils Farm and the late blight trial at the Muck Soils Research Farm are used for scab and foliar late blight assessment of lines in the agronomic trials. RESULTS A. Date of Harvest Trial Varieties: There were 17 entries that were compared at two harvest dates (98 and 141 days). Chip-processors and Tablestock (Tables 1 and 2) Atlantic, Snowden, Pike and three Frito-Lay clones were used as checks. The two new Frito-Lay clones evaluated this year were FL2053 and FL2101. The plot yields were average to above average in the early harvest (98 days), and specific gravity values were more typical to an average year. On average, there was only a 35 cwt/a increase in yield for the second harvest date (141 days). The results are summarized in Tables 1 and 2. Hollow heart and vascular discoloration were the most prevalent internal defects this year. FL1879, Atlantic, and FL2101 showed the highest incidence of hollow heart in the early harvest. There was a high incidence of above-average hollow heart in the late harvest ranging from FL1879 (43%), Beacon Chipper, Atlantic, Snowden, FL2101, to FL2053 (23%). In the early harvest trial, the best yielding lines were FL1879, MSN105- 1, and MSM171-A. MSN105-1 is a round-white tablestock line with bright skin, excellent type, moderate scab resistance, moderate foliar late resistance, and an early maturity. MSM171-A is also a round-to-oblong white tablestock line with scab resistance, strong foliar late resistance, and an early maturity. The highest yielder for the late harvest was FL1879, followed by MSJ036-A, Snowden, MSN105-1, MSJ316-A, and MSM171-A. MSJ036-A has high yield potential and shows scab resistance and chip- processing potential. MSJ316-A continues to be a consistent yielding line with scab resistance. MSJ147-1 is showing promise as a chipper out of colder and long term storage, and we were surprised by the low yield seen in 2007. In addition, MSJ036-A, MSJ126-9Y, MSJ316-A, MSH228-6, MSK061-4, and MSK409-1 offer scab resistance. The out-of-the-field chip scores for 2007 were more typical than we have seen in past years. All chip-processing lines made excellent chips out of the field, with many having above average chip quality (i.e. chip scores marked as 1.0! for Beacon Chipper, MSH228-6, MSJ147-1, MSK061-4, MSK409-1, and FL2101). 27 MSJ126-9Y – an earlier season chip-processing line with excellent chip quality MSJ147-1 – a full season storage chipper that also has some early sizing. It has MSK061-4 – an attractive round-white chip-processing line with good scab Beacon Chipper – a chip processing line that has high yield potential and MSH228-6 – a chip-processing line with moderate scab resistance. It has a good MSJ316-A – an MSU chip-processing selection. Has high yield potential and Variety Characteristics moderate scab tolerance along with excellent chip-processing quality. Beacon Chipper was named and released in 2005. type and has performed well in on-farm trials. MSJ036-A – an MSU chip-processing selection with high yield potential. It also has a high specific gravity and scab resistance. The tuber type of MSJ036-A is round and attractive. and long-term storage potential. This line also has moderate scab resistance and an attractive type. excellent chip-processing quality and a large percentage of A-size tubers. It has performed well in on-farm trials and has demonstrated an excellent long-term storage chipping profile. scab resistance and bright skin appearance. Currently in on-farm trials. There are concerns of Pike-type necrosis occurring sporadically. resistance. This line produces clean chips with good specific gravity and average yield, with low blackspot bruising. earlier maturing line has average yield and slightly lower specific gravity. strong foliar late blight resistance. This line also has an early maturity with an attractive set of tubers. blight resistance, moderate scab resistance, and an early maturity. This newer line produces excellent chips with a high specific gravity and low incidence of internal defects. MSK409-1 – a round-white chip-processing line with good scab resistance. This MSM171-A – a round-white tablestock line in moderate scab resistance and MSN105-1 – an attractive round-white tablestock line with moderate foliar late MSN191-2Y – an MSU chip-processing selection with a very uniform round type. 28 In December 2004, 2005 and 2007, MPIC sponsored a booth at the Great Lakes Expo to market Liberator, Michigan Purple and Jacqueline to the farm market/roadside stand market segment. The booth was not at the Great Lakes Expo in 2006 due to a scheduling conflict. There is an increasing interest in specialty potato varieties and a growing demand for new, unique potato varieties. We also show-cased some of the newer up-and-coming selections from the breeding program to get a sense of the interest from growers who stopped by the booth. The description of two of these varieties that fit the specialty potato market are below. MICHIGAN PURPLE - a tablestock selection with an attractive purple skin. This selection has high yield potential and the tubers have a low incidence of internal defects. The vine maturity is mid-season to mid-early. Do not let the tubers oversize. A thin skin makes this variety a challenge market on a large scale without making adjustments in harvest, washing and grading process. We regard this as a variety that can compete in the red market. It has great potential in the roadside stand and farm markets. JACQUELINE LEE – an MSU oval/oblong tablestock selection with a high tuber set. The tubers have the bright skinned, smooth and attractive appearance that is typical of many European cultivars. The tubers have very low incidence of internal defects and good baking quality. It is our best tasting potato! The strength of this selection is also its strong foliar resistance to the US8 genotype of late blight. Vine maturity is similar to Snowden. There is interest in California to market this variety. It has great potential in the roadside stand and farm markets. B. regional locations) to provide adaptability data for the release of new varieties from North Dakota, Minnesota, Wisconsin, Michigan and Canada. The funding situation in 2007 negatively affected the number of entries for these trials. Eleven breeding lines from 3 universities and 6 varieties were tested in Michigan in 2007 (compared to 18 breeding lines from 5 universities in 2006). The clones were incorporated in the Round White (4 entries), Russet (5 entries), or Red-Skinned (2 entries) trials according to market class, and the results are presented in Tables 3, 4, and 5. These lines are designated with the superscriptNCR in the tables. The MSU lines MSJ316-A, MSI005-20Y and MSA8254-2BRUS were the Michigan representatives included in the 2007 North Central Trial. MSJ316-A has a uniform type with scab resistance and good chip quality. MSI005-20Y is a yellow-fleshed line with high yield potential and an attractive round appearance. The russet line MSA8254-2BRUS has good agronomic characteristics including high yield potential and strong scab resistance. The most promising Wisconsin selections were W2324-1 (the highest yielder in the Round White Trial) and W2133-1. The North Central Trial is conducted in a wide range of environments (11 North Central Regional Trial Entries (Tables 3, 4, 5) 29 Round White Varieties (Table 3) Russet Varieties (Table 4) The russet trial had 18 lines evaluated in 2007 after 127 days. Russet Burbank C. The 17 lines in the Round White Trial consisted mainly of the round-white chip- processing entries from the North Central Regional Trial, as well as other breeding lines from New York, Wisconsin, and Colorado. The trial was harvested 134 days after planting. The top yielding lines were W2324-1, CO96141-4W, and MSJ316-A. The specific gravities were low comparable to a typical year in Michigan (1.078 for Atlantic, 1.074 for Snowden). Hollow heart and vascular discoloration were the predominant internal defects. The greatest hollow heart was seen in W2564-2 (43%), Atlantic (30%) and AC97097-14W (28%). Vascular discoloration was above average as noted in Snowden (58%). D. and Russet Norkotah were the reference varieties used in the trial and the results are summarized in Table 4. Scab resistance was prevalent among the lines tested. Hollow heart and vascular discoloration were the most prevalent internal defects. The most hollow heart was observed in CORN-3 (53%), A93157-6LS (48%), and AND98324- 1RUS (43%). Specific gravity measurements were below average with Russet Burbank and Russet Norkotah having 1.071 and 1.065 readings, respectively. The yield of the overall trial was below average for 2007, which has been typical for the Russet trials at the Montcalm Research Farm. Off type and cull tubers were found in nearly all lines tested, with the greatest pickouts from Russet Burbank (17%). Vine maturity varied among lines but it did not correlate with yield. The highest yielding entry was W5716- 1RUS, a new breeding line from Wisconsin. MSA8254-2BRUS is a high yielding MSU selection with excellent scab resistance that has also performed well in on-farm trials. Two of the Colorado Russet Norkotah Line Selections were also evaluated (CORN-3 and CORN-8). Two of the russets evaluated are being considered for release from Idaho (A93157-6LS) and Wisconsin (W2683-2RUS). E. Red-Skinned Varieties (Table 5) Eleven lines were harvested in the red trial in 2007 after 127 days. The highest yielding line was Red Pontiac, followed by ATND98459-1RY and Michigan Purple. In general, internal quality was good, with only Red Pontiac having 20% hollow heart. Among the reds in this trial, scab tolerance was noted in ND5002-3R, ND4659-5R, W2609-1R, and W3882-1R. MSL228-1 has unique splashes of color around the eyes that may make it attractive to the specialty market. This line is being considered for license to Garden’s Alive for catalog sales to home gardeners. 30 In the tablestock trial, Yukon Gold was the check variety and 13 advanced F. The Adaptation Trial was divided into chip-processing and tablestock trials. The majority of the lines evaluated in the Adaptation Trial were tested in the Preliminary Trial the previous year. Three reference cultivars (Atlantic, Snowden and Pike), and 16 advanced breeding lines are reported in the chip-processing trial. The trial was harvested after 141 days and the results are summarized in Table 6. The line MSJ461-1, which has chip quality and strong foliar late blight resistance, was the highest yielding line (145 cwt/a greater than Snowden). Multiple new breeding lines combine scab resistance and chip-processing: MSN190-2, MSN238-A, MSP516-A, MSQ029-1, MSQ070-1, MSQ089-1, and MSQ492-2. Of these lines, some also combine late blight resistance, scab resistance, and chip-processing: MSP516-A, MSQ029-1, MSQ070-1, and MSQ492- 2. MSQ029-1 also has resistance to PVY. MSL268-D has foliar late blight resistance. MS246-B is a good chip-processing line that has yield potential and a specific gravity comparable to Atlantic. breeding lines are summarized in the table. The trial was harvested after 134 days and the results are summarized in Table 7. In general, the yield was good in this trial and internal defects were low. Seven of the 13 lines have late blight resistance (including Jacqueline Lee) and 3 lines have moderate to strong scab resistance. Seven of the 13 lines also had early maturity, often combined with scab and/or late blight resistance. Boulder and MSK498-1 were the highest yielding lines and also have moderate scab resistance. Promising lines with attractive type for the tablestock market and strong foliar late blight resistance include MSL106-AY, MSL183-AY, MSM182-1, MSM137-2, MSQ176-5, and MSQ440-2. MSQ440-2 has excellent type and combines scab and late blight resistance with early maturity. MSM182-1 also has PVY resistance. Another line that has a very attractive, smooth type and bright skin is MSN084-3. It is exciting to see lines with combined traits for type, scab, late blight, and PVY resistance, and earlier maturity classes in more advanced selections in the breeding program. G. Preliminary Trial (Tables 8 and 9) selections from the MSU potato breeding program. The division of the trials was based upon pedigree assessment for chip-processing and tablestock utilization. The chip- processing Preliminary Trial had 37 advanced selections and two check varieties (Atlantic and Snowden). The chip-processing trial that is summarized in Table 8 was harvested after 135 days. Most lines chip-processed well from the field. Specific gravity values and yields were average for the trial. Twenty-two of the lines (60%) were also classified to be resistant or moderately resistant to scab (< 1.5 in 2007). Eight lines have demonstrated late blight resistance and 3 are moderately late blight resistant. Many of these lines combine chip quality with scab and late blight resistance/moderate resistance (MSQ035-3, MSQ130-4, MSQ134-5, MSR036-5, MSR041-5, MSR061-1, MSR102-3, The Preliminary trial is the first replicated trial for evaluating new advanced Adaptation Trial (Tables 6 and 7) 31 Table 9 summarizes the 36 tablestock lines evaluated in the Preliminary Trial, and MSR160-2Y). The two highest yielding lines were MSQ341-BY and MSR127-2. The two lines MSR061-1 and MSR160-2Y also have PVY resistance. including material from South Africa (Reba was used as the check variety). This tablestock trial was harvested and evaluated after 127 days. Five of the 35 lines were late blight resistant, and 11 were scab resistant or moderately resistant. One line, MSP084-3 has good yield potential and moderate resistance to Colorado potato beetle. MSS582-1, MSM224-1, and Michigan Purple Red Sport were the highest yielding lines. MSM183-1 and MSQ086-3 have good type and late blight resistance. MSM288-2Y has an excellent type, strong yellow flesh, and good scab tolerance. A few of the lines in this trial were considered for their unique color attributes for the specialty potato market: Michigan Purple Red Sport, MSQ461-2PP, MSR186-3P, MSQ558-2RR, MSR217-1R, MSQ443- 1RR. The purple and red flesh-pigmented lines MSQ461-2PP and MSQ558-2RR have also chipped out of the field. Interestingly, the South African lines were among the lowest yielding lines: Eden, Mnandi (late blight resistant), Darius, Calibra, Van der Plank, Caren, BP-1, Devlin, Esco, and Ronn. H. Transgenic Trial (Table 10) A field trial was conducted to continue to evaluate transgenic potato lines for agronomic performance. The results are summarized in Table 10. The trial this year (113 days) was used to evaluate a variety of different transgenic material. The Spunta RB line has the RB gene cloned from S. bulbocastanum which confers resistance to late blight. Three other lines express the Bt-cry3A gene which controls Colorado potato beetle (NO8.8, NO8.28 from Norwis, and YG8.8 from Yukon Gold). The majority of the lines were selections from two crosses to combine late blight resistance with the Bt- cry1Ia1 gene (from SpuntaG2) for resistance to potato tuberworm (Phthorimaea operculella). There were 10 selections from the MSR605 family (SpuntaG2 x MSJ461- 1) and 7 from the MSR606 family (SpuntaG2 x Jacqueline Lee). These selections had a range of performance for yield, specific gravity, and maturity. I. conducted to assess resistance to common scab. We are using a modified scale of a 0-5 ranking based upon a combined score for scab coverage and lesion severity. Usually examining one year's data does not indicate which varieties are resistant but it should begin to identify ones that can be classified as susceptible to scab. Our goal is to evaluate important advanced selections and varieties in the study at least three years to obtain a valid estimate of the level of resistance in each line. Table 11 categorizes many of the varieties and advanced selections tested in 2007 at the MSU Soils Farm Scab Nursery over a three-year period. The varieties and breeding lines are placed into six arbitrary categories based upon scab infection level and lesion severity. A rating of 0 indicates zero infection. A score of 1.0 indicates a trace amount of infection. A moderate Potato Scab Evaluation (Table 11) Each year, a replicated field trial at the MSU Soils Farm (E. Lansing, MI) is 32 In 2007, the late blight trial was conducted at the Muck Soils Research Farm, resistance (1.2 – 1.8) correlates with <10% infection. Scores of 4.0 or greater are found on lines with >50% infection and severe pitted lesions. The check varieties Russet Burbank, Russet Norkotah, Red Norland, NorValley, Yukon Gold, Red Pontiac, Pike, Atlantic and Snowden can be used as references (bolded in Table 11). In general, most russet lines were scab resistant. This year’s results continue indicate that we have been able to breed numerous lines for the chip-processing and tablestock markets with resistance to scab. A total of 84 lines, of the 167 tested, had a scab rating of 1.5 or lower in 2007. Most notable scab resistant MSU lines are MSA8254-2BRUS, MSH228-6, MSJ036-A, MSJ126-9Y, MSK061-4, MSK409-1, MSM171-A, MSM288-2Y, MSN073-2, MSN238-A, and MSP516-A; as well as some earlier generation lines MSQ070-1, MSQ089-1, MSQ289-5, MSQ440-2, MSR036-5, and MSR061-1. The greater number of MSU lines in the resistant and moderately resistant categories indicates we are making progress in breeding more scab resistant lines for the chip-processing and tablestock markets. Scab results from the disease nursery are also found in the Trial Summaries (Tables 2-10). J. Late Blight Trial (Table 12) Bath, MI. This year 147 entries were planted for evaluation in replicated plots. The field was planted on June 11 and inoculated July 27 with a combination of isolates (see Table 12). The late blight differential lines LBR8 and LBR9 were resistant in 2007 as in previous years (not shown in table). Twenty-eight MSU lines were highly resistant to late blight. The late blight resistance of the MSU lines is derived from Tollocan (a Mexican variety), B0718-3 (USDA clone), AWN96518-2 (USDA clone), Stirling (Scottish variety), Torridon (Scottish variety), NY121 (Cornell University clone) Jacqueline Lee (MSU variety), and the wild potato species S. microdontum and S. berthaultii. The line RB Spunta has resistance derived from a gene cloned from S. bulbocastanum. These resistant progeny indicate that we can continue to breed for resistance using this group of resistant clones. We find these late blight resistant lines valuable because many of them also have marketable maturity and some are more tolerant to scab as compared to the first generation of late blight resistant lines. Also, some of these lines have chip-processing quality. The MSU Muck Soils Research Farm continues to be an excellent site for evaluating foliar late blight resistance in inoculated field trials. Tuber late blight resistance is currently being evaluated on many of the selections with foliar late blight resistance. K. Potato Early Die Trial (Table 13) Montcalm Potato Research Farm for tolerance to the Early-Die Disease Complex. This trial has traditionally been conducted by Dr. George Bird and his team. For 2007, the breeding program worked with Dr. Bird for planting, harvesting, and data collection. Sixteen breeding lines and control varieties were evaluated in 2007. The results of the Since 1998, selected potato varieties and lines have been evaluated annually at the 33 trial were somewhat surprising in that multiple lines did not demonstrate a yield advantage for fumigated versus non-fumigated conditions (Table 13). The control variety Russet Norkotah exhibited high levels of susceptibility, although Atlantic did not. This may be a result of the unusually low yield performance of Atlantic in this trial. The surprisingly low yields of many of the lines in this trial may also contribute to differentiating yield differences between fumigated and non-fumigated plots. Over the previous nine years, the variety Boulder has been classified as tolerant to Blackspot Bruise Susceptibility (Table 14) Evaluations of advanced seedlings and new varieties for their susceptibility to PED, which was not the case this year. The breeding line MSJ461-1 did exhibit some tolerance this year and was one of the most Verticillium-resistant clones evaluated by Dr. Shelley Jansky (USDA/ARS, U. of Wisconsin, pers. comm.). Additional years of testing should help in classifying the PED resistance in potato breeding lines. The rootlesion nematode population pressure is not reported in this trial. L. blackspot bruising are also important in the variety evaluation program. Based upon the results collected over the past years, the non-bruised check sample has been removed from our bruise assessment. A composite bruise sample of each line in the trials consisted of 25 tubers (a composite of 4 reps) from each line, collected at the time of grading. The 25 tuber sample was held in 50°F storage overnight and then was placed in a hexagon plywood drum and tumbled 10 times to provide a simulated bruise. The samples were peeled in an abrasive peeler in October and individual tubers were assessed for the number of blackspot bruises on each potato. These data are shown in Table 13. The bruise data are represented in two ways: percentage of bruise free potatoes and average number of bruises per tuber. A high percentage of bruise-free potatoes is the desired goal; however, the numbers of blackspot bruises per potato is also important. Cultivars which show blackspot incidence greater than Atlantic are approaching the bruise-susceptible rating. In addition, the data is grouped by trial, since the bruise levels can vary between trials. Conducting the simulated bruise on 50°F tubers has helped to standardize the bruise testing. We are observing less variation between trials since we standardized the handling of the bruise sample. resistant lines this year from the advanced trials were MSJ126-9Y, MSN105-1, FL2101, MSK061-4, MSM102-A, MSQ089-1, MSQ440-2, MSL106-AY, MSL183-AY, MSN073-2, ND6095-1, MSP292-7, MSQ130-4, MSR159-2, MSM288-2Y, MSP197-1, MSJ316-A, and MSA8254-2BRUS. The most susceptible lines from the advanced trials were Atlantic, Beacon Chipper, Snowden, MSP516-A, MSP115-3, MSR127-2, MSR158- 4, AC97097-14W, and Canela. The bruise resistant MSU entries in the US Potato Board/Snack Food Association Trial were MSJ147-1, and MSJ316-A. Beacon Chipper was the most bruise susceptible in this trial. In 2007, the bruise levels were comparable to previous years. The most bruise 34 Table 1 DATE OF HARVEST TRIAL: EARLY HARVEST MONTCALM RESEARCH FARM May 8 to August 13, 2007 (98 days) MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS PERCENT (%) 3-YR AVG TOTAL CWT/A PERCENT OF TOTAL1 US#1 378 363 349 327 307 293 269 267 244 240 238 236 233 224 215 136 270 68 US#1 Bs As OV PO 2 95 92 0 1 96 1 96 0 91 90 4 0 92 0 91 85 2 1 88 0 92 0 97 90 0 1 93 0 89 67 0 LINE FL1879 MSN105-1LBMR MSM171-ALBR Atlantic Snowden FL2053 MSJ316-A FL2101 MSK409-1 MSK061-4 Pike Beacon Chipper MSN191-2Y MSJ126-9Y MSH228-6 MSJ147-1 MEAN LSD0.05 LBR Line(s) demonstrated foliar resistance to Late Blight ( Phytopthora infestans ) in inoculated field trials at the MSU Muck Soils Research Farm. 1SIZE: B: < 2 in.; A: 2-3.25 in.; OV: > 3.25 in.; PO: Pickouts. 2CHIP SCORE: Snack Food Association Scale (Out of the field); Ratings: 1-5; 1: Excellent, 5: Poor. 3QUALITY: HH: Hollow Heart; BC: Brown Center; VD: Vascular Discoloration; IBS: Internal Brown Spot. Percent of 40 Oversize and/or A-size tubers cut. SP GR 1.072 1.081 1.061 1.084 1.078 1.090 1.073 1.089 1.081 1.081 1.079 1.079 1.087 1.074 1.081 1.081 1.079 0.004 399 395 363 341 336 324 292 295 286 272 258 243 260 239 243 204 297 72 70 88 66 86 86 85 85 88 85 86 89 82 88 87 88 67 TUBER QUALITY3 CHIP SCORE2 HH VD IBS BC 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1.0 1.5 3.0 1.0 1.5 1.5 2.0 1.5 1.0 1.5 1.0 1.0 1.0 2.0 1.0 2.0 48 3 5 28 13 8 0 23 0 0 5 5 5 3 0 0 0 0 0 3 8 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 25 4 30 10 5 5 7 3 1 2 3 16 2 7 0 0 4 8 3 3 9 6 8 9 13 11 8 3 10 5 11 33 US#1 CWT/A 287 239* 296* 259 240 277* 153 - 207* 161 171 217 - 206* 167 186 * Two-Year Average 35 Table 2 MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS DATE OF HARVEST TRIAL: LATE HARVEST MONTCALM RESEARCH FARM May 8 to September 25, 2007 (141 days) CWT/A PERCENT OF TOTAL1 PERCENT (%) CHIP TUBER QUALITY3 TOTAL 3 9 9 10 10 5 7 4 3 12 11 6 15 12 12 16 46 74 86 79 81 77 66 73 76 71 82 86 76 78 87 80 76 54 23 5 12 8 13 26 14 19 25 6 3 18 5 2 8 7 0 0 0 0 0 0 3 6 1 0 1 0 0 2 0 0 1 0 406 422 392 396 384 376 377 340 326 355 349 300 323 296 273 258 288 345 72 US#1 394 383 359 354 345 344 327 322 315 310 309 282 269 261 241 215 155 305 69 US#1 Bs As OV PO SP GR SCORE2 HH VD IBS BC SCAB4 MAT5 1.3 97 2.8 91 91 2.0 1.3 90 4.8 90 92 1.0 1.0 87 1.5 95 97 3.0 1.8 87 3.5 89 1.3 94 83 2.0 2.0 88 1.3 88 83 1.0 2.5 54 LINE FL1879 MSJ036-A† Snowden MSN105-1LBMR MSJ316-A MSM171-ALBR FL2053 Atlantic Beacon Chipper FL2101 MSH228-6 MSJ126-9Y MSK061-4 Pike MSN191-2Y MSK409-1 MSJ147-1 MEAN LSD0.05 LBR Line(s) demonstrated foliar resistance to Late Blight ( Phytopthora infestans ) in inoculated field trials at the MSU Muck Soils Research Farm. 1SIZE: B: < 2 in.; A: 2-3.25 in.; OV: > 3.25 in.; PO: Pickouts. 2CHIP SCORE: Snack Food Association Scale (Out of the field); Ratings: 1-5; 1: Excellent, 5: Poor. 3QUALITY: HH: Hollow Heart; BC: Brown Center; VD: Vascular Discoloration; IBS: Internal Brown Spot. Percent of 40 Oversize and/or A-size tubers cut. 4SCAB DISEASE RATING: MSU Scab Nursery; 0: No Infection; 1: Low Infection <5%; 3: Intermediate; 5: Highly Susceptible. 5MATURITY RATING: August 23, 2007; Ratings 1-5; 1: Early (vines completely dead); 5: Late (vigorous vine, some flowering). †MSJ036-A had a poor stand count in DOH, data from the Transgenic Trial. 1.071 1.075 1.072 1.077 1.077 1.058 1.087 1.081 1.076 1.083 1.077 1.070 1.076 1.076 1.084 1.081 1.082 1.077 0.003 43 5 30 0 8 10 23 38 40 25 0 5 0 0 3 3 7 13 8 27 0 5 0 3 8 10 5 5 5 33 10 0 13 7 1.0 ND 1.0 ND 1.0 ND 1.0 1.0 1.0! 1.0! 1.0! 1.0 1.0! 1.0 1.0 1.0! 1.0! 0 3 0 0 3 0 0 0 0 0 0 0 0 0 0 3 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 3 0 0 2.0 0.8 2.6 2.0 1.9 1.3 1.8 2.4 1.8 1.5 1.5 1.3 1.0 1.4 1.5 0.8 1.0 3-YR AVG US#1 CWT/A 348 - 318 266* 306 295* 290* 315 343 - 247 252* 221 215 - 202* 216 * Two-Year Average 36 US#1 TOTAL US#1 Bs As OV PO SP GR SCORE2 HH VD IBS BC SCAB4 MAT5 Table 3 ROUND WHITE TRIAL MONTCALM RESEARCH FARM May 8 to September 18, 2007 (134 days) CWT/A PERCENT OF TOTAL1 PERCENT (%) CHIP TUBER QUALITY3 82 92 90 85 92 87 88 84 89 82 80 85 80 85 76 81 80 5 7 10 11 7 5 11 8 11 14 17 9 19 14 23 17 20 79 84 80 82 88 63 85 70 80 75 76 74 78 84 76 78 79 13 1 1 4 1 8 1 8 0 4 2 6 1 1 1 2 1 3 8 10 3 4 24 2 13 9 7 5 11 2 1 0 3 1 556 417 423 433 394 402 383 393 341 365 350 322 319 293 326 264 270 368 68 455 386 379 368 363 350 336 329 303 299 281 273 255 249 247 215 214 312 71 LINE W2324-1NCR CO96141-4W MSJ316-ANCR SnowdenNCR NY139 W2564-2 W2133-1NCR MSI005-20YNCR CO97043-14W AC97097-14W NorValleyNCR AtlanticNCR W2978-3 CO97065-7W W2310-3 CO95051-7W W4016-4 MEAN LSD0.05 LBR Line(s) demonstrated foliar resistance to Late Blight ( Phytopthora infestans ) in inoculated field trials at the MSU Muck Soils Research Farm. NCR North Central Regional Entry 1SIZE: B: < 2 in.; A: 2-3.25 in.; OV: > 3.25 in.; PO: Pickouts. 2CHIP SCORE: Snack Food Association Scale (Out of the field); Ratings: 1-5; 1: Excellent, 5: Poor. 3QUALITY: HH: Hollow Heart; BC: Brown Center; VD: Vascular Discoloration; IBS: Internal Brown Spot. Percent of 40 Oversize and/or A-size tubers cut. 4SCAB DISEASE RATING: MSU Scab Nursery; 0: No Infection; 1: Low Infection <5%; 3: Intermediate; 5: Highly Susceptible. 5MATURITY RATING: August 23, 2007; Ratings 1-5; 1: Early (vines completely dead); 5: Late (vigorous vine, some flowering). 1.079 1.069 1.079 1.074 1.076 1.067 1.075 1.064 1.073 1.077 1.068 1.078 1.067 1.075 1.082 1.077 1.072 1.074 0.003 1.5 1.0 1.5 2.0 2.5 2.5 1.0 ND 1.0 1.0 1.5 1.0 1.0 1.0 1.0 1.0 1.5 20 3 25 13 0 43 0 0 0 28 3 30 0 0 0 0 5 28 10 10 58 20 0 8 8 15 10 13 18 5 0 0 23 10 0 3 0 0 0 0 3 0 0 0 0 3 0 0 0 0 0 0 0 0 3 0 0 0 0 3 0 0 5 0 0 0 0 0 2.5 2.3 2.0 2.6 1.5 1.0 1.8 2.0 3.0 3.3 2.0 2.5 1.5 2.0 2.0 1.5 2.7 MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS 3-YR AVG US#1 CWT/A 494* - - 378 - - 308 355 - - 304* 331 - - 231 212 - 3.5 1.0 4.5 2.5 2.8 4.5 3.5 1.8 1.5 2.0 1.3 1.8 1.0 1.3 2.0 3.0 3.5 * Two-Year Average 37 Table 4 RUSSET and LONG TYPES TRIAL MONTCALM RESEARCH FARM May 8 to September 11, 2007 (127 days) CWT/A PERCENT OF TOTAL1 PERCENT (%) TUBER QUALITY2 10 11 13 16 10 13 9 12 15 7 8 9 5 2 7 5 3 3 3 7 7 8 4 5 5 4 7 11 3 6 5 17 2 5 2 1 15 16 16 14 15 20 22 15 14 23 15 17 28 24 34 31 35 37 71 66 64 62 71 62 65 69 64 58 74 69 63 57 57 59 59 59 US#1 TOTAL 316 306 287 285 276 265 263 261 255 251 239 237 219 195 185 179 156 144 240 83 388 396 376 368 340 353 359 322 320 381 294 305 325 334 287 280 250 231 328 82 US#1 Bs As OV PO SP GR HH VD IBS BC SCAB3 MAT4 3.8 82 3.3 77 76 3.5 3.2 77 81 3.0 3.3 75 3.8 73 2.3 81 80 2.5 2.0 66 2.8 81 78 3.8 2.3 67 3.0 58 64 1.3 1.5 64 1.0 62 62 3.7 LINE W5716-1RUS W3328-1RUS CORN-3 MSA8254-2BRUSNCR AND98324-1RUSNCR MSL794-BRUSLBR W2683-2RUSNCR CO95086-8RUS A95109-1 CO97087-2RUS Canela A93157-6LS ND7882B-7RUS Russet BurbankNCR W1879-1RUSNCR CORN-8 Russet NorkotahNCR AOA95154-1 MEAN LSD0.05 LBR Line(s) demonstrated foliar resistance to Late Blight ( Phytopthora infestans ) in inoculated field trials at the MSU Muck Soils Research Farm. NCR North Central Regional Entry 1SIZE: B: < 4 oz.; A: 4-10 oz.; OV: > 10 oz.; PO: Pickouts. 2QUALITY: HH: Hollow Heart; BC: Brown Center; VD: Vascular Discoloration; IBS: Internal Brown Spot. Percent of 40 Oversize and/or A-size tubers cut. 3SCAB DISEASE RATING: MSU Scab Nursery; 0: No Infection; 1: Low Infection <5%; 3: Intermediate; 5: Highly Susceptible. 4MATURITY RATING: August 23, 2007; Ratings 1-5; 1: Early (vines completely dead); 5: Late (vigorous vine, some flowering). 1.073 1.065 1.070 1.064 1.077 1.073 1.067 1.066 1.067 1.074 1.077 1.075 1.070 1.071 1.070 1.066 1.065 1.077 1.070 0.003 10 8 53 28 43 0 3 5 3 3 3 48 0 13 5 0 3 0 8 8 3 5 28 5 13 18 15 10 20 8 8 10 8 10 0 23 3 0 3 3 0 8 3 0 0 0 0 3 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1.0 1.0 1.5 0.5 3.0 1.8 0.5 0.0 0.8 0.5 0.3 1.0 0.7 1.0 0.8 2.3 2.0 0.5 MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS 3-YR AVG US#1 CWT/A - 318* - 303 310* 328 275 266* 259* - - 235* 233* 219* 153 - 151 - * Two-Year Average 38 Table 5 LINE Red Pontiac ATND98459-1RY Michigan Purple Rio Colorado ND5002-3RNCR MSQ441-6R W2609-1R Red NorlandNCR W3882-1R ND4659-5RNCR MSL228-1 RED-SKINNED TABLESTOCK TRIAL MONTCALM RESEARCH FARM May 8 to September 11, 2007 (127 days) MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS CWT/A PERCENT OF TOTAL1 PERCENT (%) TUBER QUALITY2 US#1 TOTAL US#1 Bs As OV PO SP GR HH VD IBS BC SCAB3 MAT4 2.0 456 326 2.0 1.3 312 1.0 310 251 3.5 1.3 246 1.0 213 1.5 213 206 1.0 1.0 202 180 1.3 1.056 1.068 1.061 1.063 1.059 1.053 1.055 1.053 1.055 1.060 1.072 535 398 363 366 317 276 251 241 249 244 217 3.0 2.0 2.3 1.5 0.3 2.0 0.8 1.5 1.0 0.5 ND 69 80 73 77 76 85 84 88 83 78 80 85 82 86 85 79 89 85 88 83 83 83 9 16 8 13 20 10 14 9 16 16 8 20 0 3 13 0 0 0 0 5 0 0 5 0 3 3 8 0 3 0 8 0 10 16 2 13 7 3 4 1 0 0 5 3 6 2 6 2 1 0 1 3 1 1 9 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 314 61 265 58 MEAN LSD0.05 LBR Line(s) demonstrated foliar resistance to Late Blight (Phytopthora infestans ) in inoculated field trials at the MSU Muck Soils Research Farm. NCR North Central Regional Entry 1SIZE: B: < 2 in.; A: 2-3.25 in.; OV: > 3.25 in.; PO: Pickouts. 2QUALITY: HH: Hollow Heart; BC: Brown Center; VD: Vascular Discoloration; IBS: Internal Brown Spot. Percent of 40 Oversize and/or A-size tubers cut. 3SCAB DISEASE RATING: MSU Scab Nursery; 0: No Infection; 1: Low Infection <5%; 3: Intermediate; 5: Highly Susceptible. 4MATURITY RATING: August 23, 2007; Ratings 1-5; 1: Early (vines completely dead); 5: Late (vigorous vine, some flowering). 1.060 0.003 39 Table 6 ADAPTATION TRIAL, CHIP-PROCESSING LINES MONTCALM RESEARCH FARM May 8 to September 25, 2007 (141 days) MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS CWT/A PERCENT OF TOTAL1 CHIP TUBER QUALITY3 PERCENT (%) US#1 TOTAL US#1 Bs As OV PO SP GR SCORE2 HH VD IBS BC SCAB4 MAT5 90 90 85 88 93 91 88 93 91 80 82 88 84 88 88 85 70 68 84 9 9 14 10 7 7 9 7 5 15 17 10 16 11 8 12 20 30 14 79 83 80 76 73 83 71 85 79 75 78 80 80 85 71 81 68 64 79 11 7 5 12 19 9 17 8 12 5 4 8 3 3 17 4 2 4 5 1 1 1 2 0 1 3 0 4 5 1 1 0 1 4 3 10 2 2 425 380 369 326 322 314 279 278 276 270 262 258 255 252 247 235 230 162 147 278 71 472 422 433 370 348 343 316 300 303 336 321 292 305 285 281 276 330 240 173 323 72 LINE MSJ461-1LBR Snowden MSQ070-1LBR MSQ089-1 MSQ029-1LBR,PVYR MSQ108-1 MSL292-A MSN238-A Atlantic MSL268-DLBR MSQ492-2LBR MSM246-B MSM060-3 Pike MSN099-B MSP516-ALBR MSN313-A MSN190-2 MSM102-A MEAN LSD0.05 LBR Line(s) demonstrated foliar resistance to Late Blight (Phytopthora infestans ) in inoculated field trials at the MSU Muck Soils Research Farm. 1SIZE: B: < 2 in.; A: 2-3.25 in.; OV: > 3.25 in.; PO: Pickouts. 2CHIP SCORE: Snack Food Association Scale (Out of the field); Ratings: 1-5; 1: Excellent, 5: Poor. 3QUALITY: HH: Hollow Heart; BC: Brown Center; VD: Vascular Discoloration; IBS: Internal Brown Spot. Percent of 40 Oversize and/or A-size tubers cut. 4SCAB DISEASE RATING: MSU Scab Nursery; 0: No Infection; 1: Low Infection <5%; 3: Intermediate; 5: Highly Susceptible. 5MATURITY RATING: August 23, 2007; Ratings 1-5; 1: Early (vines completely dead); 5: Late (vigorous vine, some flowering). 1.075 1.080 1.089 1.073 1.081 1.079 1.073 1.080 1.081 1.072 1.069 1.081 1.088 1.082 1.069 1.071 1.078 1.082 1.078 1.078 0.005 1.0 1.0 1.0 1.5 1.0 1.5 1.0! 1.5 1.5 1.0 1.5 1.0! 1.0 1.0 1.0 1.0! 1.5 1.5 1.0 1.8 2.6 0.8 1.0 1.3 2.0 2.3 1.3 2.4 1.5 1.3 2.3 1.8 1.4 1.8 1.0 1.8 1.3 2.0 5 63 8 8 13 10 5 10 13 20 13 13 23 10 8 25 3 3 0 0 18 8 0 20 5 8 13 30 0 0 3 5 3 10 0 5 5 0 10 3 10 0 0 0 0 0 3 0 18 0 3 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 3.7 2.3 4.8 3.3 4.0 1.5 1.5 2.0 1.5 2.5 3.3 2.0 1.4 2.5 1.5 3.0 3.5 1.0 1.7 40 Table 7 ADAPTATION TRIAL, TABLESTOCK LINES MONTCALM RESEARCH FARM May 8 to September 18, 2007 (134 days) MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS CWT/A PERCENT OF TOTAL1 PERCENT (%) TUBER QUALITY2 96 92 89 93 88 95 86 81 82 90 91 55 85 91 2 7 7 5 10 5 13 19 13 6 8 42 13 9 50 81 80 84 85 82 85 80 79 77 69 55 83 83 46 10 9 9 4 13 1 0 3 13 22 0 3 8 2 1 4 2 2 0 1 0 5 4 1 3 2 1 US#1 TOTAL US#1 Bs As OV PO SP GR HH VD IBS BC SCAB3 MAT4 3.3 440 3.3 426 389 1.0 1.5 378 1.0 317 315 1.0 2.5 306 1.3 282 264 2.3 1.0 245 3.8 239 234 3.0 1.0 225 192 1.3 304 69 LINE Boulder MSK498-1Y MSM070-1 MSN170-A MSL183-AYLBR MSN084-3 MSM182-1LBR,PVYR MSQ425-4Y MSM137-2LBR Yukon Gold MSQ176-5LBR Jacqueline LeeLBR MSL106-AYLBR MSQ440-2LBR MEAN LSD0.05 LBR Line(s) demonstrated foliar resistance to Late Blight (Phytopthora infestans ) in inoculated field trials at the MSU Muck Soils Research Farm. 1SIZE: B: < 2 in.; A: 2-3.25 in.; OV: > 3.25 in.; PO: Pickouts. 2QUALITY: HH: Hollow Heart; BC: Brown Center; VD: Vascular Discoloration; IBS: Internal Brown Spot. Percent of 40 Oversize and/or A-size tubers cut. 3SCAB DISEASE RATING: MSU Scab Nursery; 0: No Infection; 1: Low Infection <5%; 3: Intermediate; 5: Highly Susceptible. 4MATURITY RATING: August 23, 2007; Ratings 1-5; 1: Early (vines completely dead); 5: Late (vigorous vine, some flowering). 1.076 1.064 1.072 1.076 1.061 1.056 1.067 1.064 1.064 1.070 1.060 1.075 1.060 1.053 1.066 0.004 460 466 439 408 358 332 355 349 323 272 263 425 264 212 352 66 1.8 2.0 1.5 1.3 2.8 3.0 2.0 3.0 2.3 2.8 2.0 2.3 2.8 1.0 0 28 13 13 10 23 5 15 3 8 10 3 3 23 3 0 8 0 0 0 0 0 0 15 13 0 0 0 0 0 0 0 0 0 0 0 0 3 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 41 Table 8 PRELIMINARY TRIAL, CHIP-PROCESSING LINES MONTCALM RESEARCH FARM May 8 to September 19, 2007 (135 days) MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS LINE US#1 TOTAL US#1 Bs As OV PO CWT/A PERCENT OF TOTAL1 MSQ341-BY MSR127-2 Snowden MSM205-A Atlantic MSR159-19LBMR MSR160-2YLBR PVYR MSR036-5LBR MSR156-7 MSR061-1LBMR PVYR MSP459-5 MSQ035-3LBMR MSP497-1 MSR159-10 MSN148-A MSR131-5 MSQ134-5LBR MSR159-06 MSR090-1Y MSP102-5 ND7519-1 MSR159-07Y MSR167-3Y MSR128-4Y MSR102-3LBR continued on next page: 401 373 360 352 346 341 335 326 322 321 312 312 311 311 302 302 298 282 272 272 271 266 246 243 225 439 408 411 428 364 381 430 359 348 370 375 358 351 345 370 348 343 322 292 406 313 317 303 298 263 91 92 88 82 95 90 78 91 93 87 83 87 89 90 82 87 87 88 93 67 87 84 81 81 86 8 8 12 11 3 8 22 7 7 13 13 10 9 8 17 13 13 12 4 28 11 15 16 15 11 81 84 85 81 86 71 78 80 89 86 81 79 73 79 80 87 87 79 63 67 86 81 80 77 68 10 8 3 2 9 19 0 11 4 1 3 8 15 11 2 0 0 9 30 0 1 3 2 4 17 1 0 1 7 1 2 1 2 1 0 3 3 3 1 1 0 0 0 3 5 3 2 3 4 3 PERCENT (%) CHIP TUBER QUALITY3 SP GR SCORE2 HH VD IBS BC SCAB4 MAT5 2.0 1.074 4.0 1.079 3.0 1.074 1.080 2.0 2.0 1.083 2.0 1.070 1.082 2.5 4.5 1.081 3.0 1.082 3.0 1.073 1.072 1.0 4.0 1.068 3.0 1.064 4.5 1.078 1.083 2.0 3.0 1.083 2.5 1.065 1.070 1.0 3.0 1.067 2.5 1.087 1.0 1.079 1.086 1.0 2.5 1.072 3.5 1.078 1.076 5.0 1.5 1.0 1.0 1.5 1.5 1.0 1.5 1.5 1.0 1.0 1.0 ND 1.0 1.5 1.0! 1.0 1.5 1.0 1.5 2.0 1.0 1.0 1.5 1.5 1.5 1.5 1.0 2.6 1.3 2.5 1.5 1.3 1.0 1.8 1.0 1.0 1.5 1.8 1.8 - 1.0 1.5 1.7 3.0 1.5 2.0 1.7 1.0 1.0 0.5 15 0 45 20 20 10 0 10 10 5 10 5 0 0 20 15 5 0 0 0 30 0 0 5 10 0 0 20 0 20 30 5 0 0 0 25 5 25 5 0 0 0 0 0 0 0 5 30 5 5 5 0 10 0 0 0 0 0 0 0 0 0 0 15 0 0 0 0 5 0 5 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 10 0 0 0 0 42 PRELIMINARY TRIAL, CHIP-PROCESSING LINES MONTCALM RESEARCH FARM May 8 to September 19, 2007 (135 days) LINE continued: MSQ130-4LBR MSR041-5LBR MSR125-1 MSR130-1 MSR049-4 MSP408-10YLBR MSN073-2 MSP115-3 ND8305-1 MSP292-7 ND6095-1 MSR089-14Y MSR089-9LBR ND8304-2 MEAN LSD0.05 CWT/A PERCENT OF TOTAL1 PERCENT (%) CHIP TUBER QUALITY3 US#1 TOTAL US#1 Bs As OV PO SP GR SCORE2 HH VD IBS BC SCAB4 MAT5 220 218 216 209 205 201 188 168 164 161 160 145 124 115 261 90 246 254 237 253 246 268 232 207 236 202 273 218 178 179 312 96 89 86 91 83 83 75 81 81 69 80 59 66 70 64 11 14 8 14 15 23 15 15 29 13 39 32 23 34 74 81 89 83 83 75 79 80 69 77 59 65 63 64 16 5 2 0 0 0 2 1 0 3 0 1 6 0 0 0 1 3 1 2 4 4 1 7 2 2 8 1 1.070 1.076 1.082 1.075 1.067 1.070 1.069 1.084 1.083 1.073 1.070 1.076 1.077 1.067 1.076 0.005 1.0 1.5 1.0 1.0 1.0 2.0 1.5 1.5 1.0 1.5 1.0 1.5 1.0 ND 40 0 0 0 0 0 5 65 10 5 0 0 0 0 0 10 5 10 0 5 0 15 5 0 25 30 10 25 15 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1.5 1.0 1.3 1.0 2.0 0.8 1.0 2.0 2.0 1.0 2.7 2.3 2.0 2.5 1.0 3.0 1.0 3.0 3.5 3.5 1.5 5.0 1.0 1.0 1.0 1.0 2.3 1.0 LBR Line(s) demonstrated foliar resistance to Late Blight (Phytopthora infestans ) in inoculated field trials at the MSU Muck Soils Research Farm. 1SIZE: B: < 2 in.; A: 2-3.25 in.; OV: > 3.25 in.; PO: Pickouts. 2CHIP SCORE: Snack Food Association Scale (Out of the field); Ratings: 1-5; 1: Excellent, 5: Poor. 3QUALITY: HH: Hollow Heart; BC: Brown Center; VD: Vascular Discoloration; IBS: Internal Brown Spot. Percent of 20 Oversize and/or A-size tubers cut. 4SCAB DISEASE RATING: MSU Scab Nursery; 0: No Infection; 1: Low Infection <5%; 3: Intermediate; 5: Highly Susceptible. 5MATURITY RATING: August 23, 2007; Ratings 1-5; 1: Early (vines completely dead); 5: Late (vigorous vine, some flowering). 43 Table 9 LINE MSS582-1 MSM224-1 MI Purple Red Sport Reba MSR081-14 MSR051-1 MSR158-4 MSQ461-2PP MSR605-15 MSP084-3CPBMR MSR214-2P MSM183-1LBR MSR159-2LBR MSR161-2 MSP197-1 MSQ505-4 MSM288-2Y MSQ086-3LBR NY121LBR Eden MnandiLBR MSQ279-1 Darius Calibra Van der Plank continued on next page: PRELIMINARY TRIAL, TABLESTOCK LINES MONTCALM RESEARCH FARM May 8 to Septmeber 11, 2007 (127 days) MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS PERCENT (%) CWT/A PERCENT OF TOTAL1 US#1 TOTAL US#1 Bs 4 517 10 422 7 398 383 5 15 369 11 358 356 14 9 345 18 341 340 9 9 323 20 301 15 299 297 10 8 296 9 286 286 18 11 284 28 280 280 18 21 275 3 273 253 19 13 224 219 14 577 487 451 401 439 406 415 387 426 395 372 393 360 350 350 334 356 321 399 374 359 296 324 259 278 90 87 88 95 84 88 86 89 80 86 87 76 83 85 85 86 80 88 70 75 77 92 78 87 79 As 72 78 72 68 79 85 75 80 71 86 87 73 78 80 72 56 77 85 67 75 74 71 74 76 68 OV 17 9 16 28 6 3 11 10 9 0 0 3 5 5 13 30 3 3 4 0 2 21 4 11 11 PO 6 3 4 0 1 1 0 2 2 5 4 3 2 6 7 5 1 0 2 7 2 5 4 0 7 TUBER QUALITY3 SP GR HH VD IBS BC 0 1.064 0 1.063 0 1.056 1.059 0 0 1.054 0 1.059 1.071 0 0 1.067 0 1.057 1.084 10 0 1.057 0 1.073 0 1.076 1.073 0 0 1.063 0 1.058 1.066 0 0 1.068 0 1.070 1.066 0 0 1.061 0 1.065 1.071 5 0 1.073 1.055 0 15 0 0 5 10 5 20 0 0 10 5 5 10 5 10 0 0 10 0 0 5 0 20 20 35 0 10 5 40 5 0 0 0 10 10 0 0 15 10 30 5 0 30 15 10 0 5 25 35 5 0 0 0 0 0 0 0 0 0 5 0 0 0 0 5 0 0 0 0 0 0 0 5 0 0 SCAB4 MAT5 2.0 3.5 1.0 3.0 4.5 4.5 4.0 2.0 3.5 2.0 4.5 4.5 5.0 4.5 1.0 4.0 1.0 3.0 1.0 1.5 2.5 3.5 3.5 4.0 2.5 2.0 1.8 ND 1.8 2.0 2.0 2.3 1.3 2.0 2.3 2.0 2.5 1.3 1.0 2.3 2.0 1.3 2.0 2.0 3.0 2.0 1.8 2.0 1.0 2.5 44 PRELIMINARY TRIAL, TABLESTOCK LINES MONTCALM RESEARCH FARM May 8 to Septmeber 11, 2007 (127 days) PERCENT (%) CWT/A PERCENT OF TOTAL1 US#1 TOTAL US#1 Bs As OV PO TUBER QUALITY3 SP GR HH VD IBS BC SCAB4 MAT5 4.0 2.5 4.5 2.3 2.5 1.0 1.0 5.0 5.0 5.0 4.0 77 80 70 71 80 58 72 77 63 55 48 12 15 28 14 13 42 17 22 26 37 24 77 85 72 77 85 58 77 77 63 55 48 282 248 294 270 243 311 227 149 172 161 169 334 161 216 212 211 208 207 181 174 114 108 89 81 272 145 LINE continued: Caren MSR157-1Y BP-1 MSR186-3P Devlin MSQ558-2RR MSR217-1R MSQ443-1RR Esco Ronn MSQ437-2PP MEAN LSD0.05 LBR Line(s) demonstrated foliar resistance to Late Blight ( Phytopthora infestans ) in inoculated field trials at the MSU Muck Soils Research Farm. 1SIZE: B: < 2 in.; A: 2-3.25 in.; OV: > 3.25 in.; PO: Pickouts. 2CHIP SCORE: Snack Food Association Scale (Out of the field); Ratings: 1-5; 1: Excellent, 5: Poor. 3QUALITY: HH: Hollow Heart; BC: Brown Center; VD: Vascular Discoloration; IBS: Internal Brown Spot. Percent of 20 Oversize and/or A-size tubers cut. 4SCAB DISEASE RATING: MSU Scab Nursery; 0: No Infection; 1: Low Infection <5%; 3: Intermediate; 5: Highly Susceptible. 5MATURITY RATING: August 23, 2007; Ratings 1-5; 1: Early (vines completely dead); 5: Late (vigorous vine, some flowering). 1.073 1.063 1.061 1.054 1.076 1.064 1.056 1.075 1.055 1.061 1.059 1.065 0.009 1.5 1.3 2.8 1.3 2.3 2.0 1.5 1.0 2.3 1.7 1.3 12 0 0 9 1 0 6 1 11 7 28 0 10 50 0 25 0 0 10 0 5 5 0 6 2 6 5 0 5 0 0 0 0 5 5 0 10 20 0 15 0 5 20 0 20 0 0 5 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 45 Table 10 LINE MSJ036-A Spunta RB NO8.28 NO8.8 MSR605-15 MSR605-08 MSR606-10 MSR606-08 MSR606-09 MSR605-17 MSR605-01 MSR605-14 MSR606-05 MSR605-07 MSR605-04 YG8.8 MSR605-05 MSR605-10 MSR606-02 MSR605-02 MSR606-03 MSR606-06 MEAN LSD0.05 TRANSGENIC TRIAL MONTCALM RESEARCH FARM May 17 to September 6, 2007 (113 days) MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS CWT/A PERCENT OF TOTAL1 PERCENT (%) TUBER QUALITY2 US#1 TOTAL US#1 Bs As OV PO SP GR HH VD IBS BC MAT3 2.8 383 2.8 321 306 2.3 2.0 296 3.3 267 1.0 255 251 3.0 1.5 246 2.3 221 197 3.0 2.3 187 1.5 185 1.0 178 177 2.7 2.7 171 1.0 170 144 1.0 2.3 141 1.5 138 1.3 137 130 1.0 1.0 99 1.075 1.057 1.061 1.063 1.062 1.058 1.069 1.072 1.066 1.070 1.062 1.063 1.059 1.058 1.063 1.071 1.065 1.066 1.059 1.056 1.059 1.056 422 374 321 308 329 290 321 381 288 253 225 217 219 210 221 189 204 177 182 194 194 177 86 62 87 83 75 79 74 64 73 73 80 85 72 78 73 87 70 78 71 71 65 56 91 86 95 96 81 88 78 65 77 78 83 86 81 84 77 90 70 79 76 71 67 56 9 8 4 4 17 8 16 34 20 15 11 10 13 12 17 9 29 21 23 25 30 40 5 23 9 13 6 9 4 0 4 5 3 1 10 7 5 3 0 1 4 0 2 0 0 6 0 0 2 4 6 2 3 7 6 4 5 3 5 1 1 0 1 4 3 3 5 0 0 0 0 0 13 0 0 0 3 0 0 0 0 3 0 0 0 0 0 0 8 78 15 10 10 20 20 18 20 25 3 3 8 0 20 13 5 0 15 13 13 3 3 8 0 0 0 3 0 55 0 0 0 0 0 17 10 0 5 0 0 0 0 0 3 3 0 3 0 3 0 0 0 3 0 0 0 13 0 0 0 0 0 3 0 3 209 73 259 79 1.063 0.003 1SIZE: B: < 2 in.; A: 2-3.25 in.; OV: > 3.25 in.; PO: Pickouts. 2QUALITY: HH: Hollow Heart; BC: Brown Center; VD: Vascular Discoloration; IBS: Internal Brown Spot. Percent of 40 Oversize and/or A-size tubers cut. 3MATURITY RATING: August 23, 2007; Ratings 1-5; 1: Early (vines completely dead); 5: Late (vigorous vine, some flowering). 46 Table 11 MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS 3-YR* AVG. - 0.6* 0.4 - - - 0.2 - - 0.4 0.8 0.7* 0.9 0.8 1.2 - 0.4 - 1.0 - 1.6 1.0 1.3 1.2 1.4 1.0* LINE Sorted by ascending 2007 Rating; CO95086-8RUS Canela ND5002-3RNCR AOA95154-1 CO97087-2RUS MSA8254-2BRUS MSR102-3 ND4659-5R W2683-2RUSNCR A95109-1 ND7882B-7RUSNCR MSJ036-A MSK409-1 MSP408-10Y MSQ070-1LBR W1879-1RUSNCR W2609-1R A93157-6LS Calibra MSJ147-1 MSK061-4 MSN073-2 MSP292-7 MSP459-5 MSP516-ALBR MSQ089-1 MSQ289-5 MSQ440-2 MSQ443-1RR MSR036-5 MSR041-5 MSR061-1 MSR127-2 MSR128-4Y MSR130-1 MSR131-5 MSR161-2 MSR167-3Y Russet BurbankNCR W2564-2 W3328-1RUS W3882-1R W5716-1RUS 0.8* 1.4* - - - - - - - - - - 1.6* 1.3* - - - 2005-2007 SCAB DISEASE TRIAL SUMMARY SCAB NURSERY, EAST LANSING, MI 2006 2007 2006 2007 2007 RATING WORST N 2006 RATING WORST N 2005 2005 RATING WORST N 2005 0.0 0.3 0.3 0.5 0.5 0.5 0.5 0.5 0.5 0.7 0.7 0.8 0.8 0.8 0.8 0.8 0.8 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 1 1 1 1 1 1 1 1 1 1 3 1 1 1 1 1 1 1 1 1 1 1 2 1 2 4 4 4 4 4 4 2 4 8 3 3 4 4 4 4 4 4 4 1 4 4 4 4 4 4 3 4 4 4 3 2 4 3 3 2 1 3 1 4 4 4 4 4 0.3 - 1.0 - - 0.0 - - 0.3 1.7 0.8 1.2 1.0 1.8 - 0.3 - 1.4 - 1.8 1.3 1.3 1.7 2.0 1.0 - 0.5 1.8 - - - - - - - - - - 2.3 - 1.5 - - 1 - 1 - - 0 - - 1 3 1 2 1 2 - 3 - 3 - 2 2 2 2 2 1 - 1 2 - - - - - - - - - - 2 - 2 - - 4 - 4 - - 4 - - 4 3 4 3 4 3 - 4 - 4 - 4 3 4 3 4 1 - 4 4 - - - - - - - - - - 4 - 4 - - 1.0 - - - - 0.0 - - 0.3 0.0 - 0.8 0.7 1.0 - 0.3 - 0.8 - 2.0 0.8 1.5 1.0 1.3 - - - - - - - - - - - - - - - - - - - 1 - - - - 0 - - 1 0 - 1 1 2 - 1 - 2 - 2 1 2 1 2 - - - - - - - - - - - - - - - - - - - 3 - - - - 5 - - 6 4 - 4 3 4 - 3 - 4 - 4 4 2 4 3 - - - - - - - - - - - - - - - - - - - 47 - - - - 1.7* 3-YR* AVG. 1.5* 1.3 - 1.0 1.2 - - - 1.4 1.3 - LINE Sorted by ascending 2007 Rating; MSJ126-9Y MSM046-4 MSM058-A MSM171-ALBR MSM205-A MSM288-2Y MSN170-A MSN190-2 MSN238-A MSQ461-2PP MSQ492-2LBR MSR066-1 MSR157-1Y MSR159-2 MSR160-2Y MSQ029-1LBR MSQ437-2PP MSR125-1 MSR186-3P Pike Caren CO95051-7W CORN-3 FL2101 MSH228-6 MSL183-AYLBR MSL268-DLBR MSM070-1 MSN191-2Y MSP102-5 MSQ035-2LBR MSQ130-4 MSQ134-5 MSQ341-BY MSR090-1Y MSR159-19 MSR217-1R NY139 Red NorlandNCR Rio Colorado W2978-3 MSM183-1 MSR159-06 MSR159-07Y Ronn - - - 1.2 1.8* 1.1 - - 1.3 2.2 1.6 - 1.8 - - - - - - - - - - - - - - 1.3* 2.3* 2005-2007 SCAB DISEASE TRIAL SUMMARY SCAB NURSERY, EAST LANSING, MI 2006 2007 2006 2007 2007 RATING WORST N 2006 RATING WORST N 2005 2005 RATING WORST N 2005 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.4 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.7 1.7 1.7 1.7 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 3 2 2 2 2 2 2 2 2 2 3 3 2 2 2 3 2 2 3 2 2 3 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 3 3 3 3 8 4 4 4 4 4 2 4 4 4 4 2 4 4 2 4 4 2 4 4 4 4 3 3 3 3 1.5 - 1.0 1.3 - - - 1.6 1.5 - 1.8 - - - - 2.0 - - - 1.4 2.0 1.4 - - 1.4 3.0 2.3 - 2.5 - 3.0 - - - - - - - 1.0 - - - - - - 2 - 1 2 - - - 2 2 - 2 - - - - 2 - - - 2 2 2 - - 2 3 3 - 3 - 3 - - - - - - - 2 - - - - - - 4 - 4 4 - - - 4 4 - 3 - - - - 1 - - - 7 4 4 - - 4 3 4 - 4 - 2 - - - - - - - 4 - - - - - - 1.0 - 0.8 1.0 - - - 1.3 1.0 - - - - - - - - - - 1.0 - 0.5 - - 1.0 2.0 1.0 - 1.5 - - - - - - - - - - - - - - - - 1 - 1 1 - - - 2 1 - - - - - - - - - - 1 - 1 - - 1 2 2 - 2 - - - - - - - - - - - - - - - - 3 - 4 3 - - - 4 4 - - - - - - - - - - 8 - 2 - - 4 4 4 - 2 - - - - - - - - - - - - - - - - 48 3-YR* AVG. - 1.5 1.7* 2.1* - 1.6 1.8 1.5 - 1.4 1.9 - - - - - - 1.6 1.5 - - LINE Sorted by ascending 2007 Rating; A96517-2 Beacon Chipper Boulder FL2053 MSJ143-4 MSJ461-1LBR MSL794-BRUSLBR MSM060-3 MSM224-1 MSN099-B MSN313-A MSP497-1 MSQ279-1 MSR089-9 MSR156-7 MSR159-10 Reba W2133-1NCR MSJ316-A ATND98459-1RY CO97065-7W Darius FL1879 Mnandi MSI005-20YNCR MSK498-1Y MSM102-A MSM182-1LBR MSN105-1LBMR MSP115-3 MSQ086-3LBR MSQ108-1LBR MSQ176-5LBR MSQ441-6R MSQ505-4 MSQ558-2RR MSR049-4 MSR051-1 MSR081-14 MSR089-14Y MSR214-2P MSR605-15 MSS582-1 ND7519-1 2.3* 2.3 - 1.9 1.9 1.5 2.1 1.5 - 1.5* 2.2* 2.3* 2.5* - - - - - - - - - - 2005-2007 SCAB DISEASE TRIAL SUMMARY SCAB NURSERY, EAST LANSING, MI 2006 2007 2006 2007 2007 RATING WORST N 2006 RATING WORST N 2005 2005 RATING WORST N 2005 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.9 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 3 2 2 2 2 3 3 2 3 2 2 2 3 3 2 3 2 2 3 2 2 3 2 2 2 3 2 3 3 3 2 2 2 2 3 3 3 3 3 3 2 3 3 2 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 8 4 4 4 4 1 4 4 4 4 4 4 4 4 4 3 4 4 4 4 4 4 4 4 5 4 - 1.8 1.6 2.5 - 1.8 2.5 1.8 - 1.3 3.0 - - - - - - 2.0 1.6 - - 2.5 2.6 - 2.5 2.0 1.6 2.7 1.5 - 1.0 2.3 2.5 3.0 - - - - - - - - - - - 2 2 3 - 2 3 2 - 2 3 - - - - - - 2 2 - - 3 3 - 3 2 2 3 2 - 1 3 3 3 - - - - - - - - - - - 4 4 4 - 4 4 3 - 4 4 - - - - - - 4 4 - - 2 4 - 4 4 4 3 2 - 4 3 2 2 - - - - - - - - - - - 1.0 - - - 1.3 1.3 1.0 - 1.3 1.0 - - - - - - 1.0 1.0 - - - 2.3 - 1.3 1.8 1.0 1.8 1.0 - - - - - - - - - - - - - - - - 1 - - - 2 2 1 - 2 2 - - - - - - 1 1 - - - 3 - 2 2 1 2 1 - - - - - - - - - - - - - - - - 4 - - - 7 4 4 - 4 4 - - - - - - 4 4 - - - 3 - 4 4 4 4 3 - - - - - - - - - - - - - - - 49 3-YR* AVG. - 2.5* - 1.8 1.8 - - 2.2* 2.1* 2.3* 2.2 1.9 - 1.9 - 2.3 - LINE Sorted by ascending 2007 Rating; ND8305-1 NorValleyNCR NY121 Russet NorkotahNCR W2310-3 CO96141-4W CORN-8 Devlin Esco Jacqueline LeeLBR Michigan Purple MSL292-A MSM137-2 MSM246-B MSP084-3 MSP197-1 MSR158-4 Saginaw Gold Atlantic ND8304-2 Van der Plank W2324-1NCR SnowdenNCR W4016-4 BP-1 MSL106-AY ND6095-1 Yukon Gold AND98324-1RUS CO97043-14W Eden MSN084-3 MSQ425-4Y Red Pontiac AC97097-14W 2.8* 2.6 - - - 2.3* 2.3 - - 2.6* 2.5 - 3.0* 2.5* - - - - 2005-2007 SCAB DISEASE TRIAL SUMMARY SCAB NURSERY, EAST LANSING, MI 2006 2007 2006 2007 2007 RATING WORST N 2006 RATING WORST N 2005 2005 RATING WORST N 2005 2.0 2.0 2.0 2.0 2.0 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.4 2.5 2.5 2.5 2.6 2.7 2.8 2.8 2.8 2.8 3.0 3.0 3.0 3.0 3.0 3.0 3.3 3 3 2 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 4 4 3 3 3 4 3 4 1 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 16 4 2 4 18 3 4 4 4 4 1 4 4 1 1 4 3 - 3.0 - 2.2 1.8 - - 2.2 2.0 - 2.8 2.5 - 2.4 - 3.0 - 2.3 2.8 - - 2.6 2.8 - 2.3 - - - 3.0 - 2.5 2.5 - - - - 3 - 3 3 - - 3 2 - 3 3 - 4 - 3 - 3 3 - - 3 3 - 3 - - - 4 - 3 3 - - - - 4 - 3 4 - - 3 1 - 4 4 - 4 - 4 - 4 16 - - 4 16 - 4 - - - 4 - 4 4 - - - - - - 1.3 1.5 - - - - 2.3 1.5 1.0 - 1.0 - 1.5 - - 1.6 - - - 2.0 - - - - - - - - 2.3 - - - - - - 2 2 - - - - 3 2 1 - 2 - 2 - - 2 - - - 3 - - - - - - - - 3 - - - - - - 4 4 - - - - 4 6 3 - 4 - 4 - - 11 - - - 12 - - - - - - - - 4 - - - SCAB DISEASE RATING: MSU Scab Nursery plot rating of 0-5; 0: No Infection; 1: Low Infection <5%, no pitted leisions; 3: Intermediate >20%, some pitted leisions (Susceptible, as commonly seen on Atlantic); 5: Highly Susceptible, >75% coverage and severe pitted leisions. LSD0.05 = LBR Line(s) demonstrated foliar resistance to Late Blight ( Phytopthora infestans ) in inoculated field trials at the MSU Muck Soils Research Farm. NCR North Central Regional Entry N = Number of replications (observations). 0.9 0.9 0.9 50 Table 12 2007 LATE BLIGHT VARIETY TRIAL MUCK SOILS RESEARCH FARM MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS RAUDPC1 LINE Sorted by ascending RAUDPC value: MEAN Female Male LINE RAUDPC1 MEAN MSJ461-1 MSG274-3 MSJ461-1 S. bulbocastanum SFH NY103 0.0 0.0 0.7 0.8 0.9 1.0 1.0 1.0 1.2 1.3 1.6 1.7 1.8 1.9 2.2 2.3 2.3 2.3 2.4 2.4 2.5 2.5 2.6 2.9 3.4 3.4 3.7 4.1 4.2 4.3 4.9 5.0 5.0 5.0 5.5 6.4 6.4 7.3 7.5 8.8 10.5 MSG141-3 9.6 Pike MSG004-3 MSE230-6 Onaway NY121 MSL757-1 Stirling K214-1R MSB106-7 J. Lee Tollocan J. Lee Eramosa Stirling A95053-61 MSJ461-1 NY88 MSJ461-1 S. microdontum MSK061-4 Tollocan Pike S. berthaultii MSI152-A Torridon S. berthaultii MSI152-A Foliar Susceptibility Category (select lines) 2 : CORN-3 MSJ036-A MSJ316-A MSH228-6 W2324-1 W2133-1 MSJ147-1 FL2101 Yukon Gold Snowden Beacon Chipper Rio Colorado W1879-1RUS MSI005-20Y W3328-1RUS A93157-6LS W5716-1RUS ATND98459-1RY W2978-3 Atlantic MSA8254-2BRUS NY139 FL1879 Russet Burbank Pike MSK061-4 NorValley AC97097-14W CORN-8 CO97065-7W MSJ126-9Y FL2053 Russet Norkotah CO97043-14W Red Norland Reba Saginaw Gold Foliar Resistance Category (select lines): J138K6A22 Kufri Jeevan BER 141 MSQ176-5 MSM183-1 BER 83 MSQ176-6 LBR9 LBR8 MCR 205 97A-51 MCR 140 MSQ070-1 MSJ461-1 MSP516-A ND99362B-1RUS MCR 150 Malinche MSL268-D MCR 214 MSN230-6RY MSM137-2 391046.22 MSM182-1 MSL794-BRUS B0718-3 MSQ492-2 MSQ134-5 MSL106-AY MSQ086-3 MSR160-2Y ND039051B-1R MSL603-319Y Jacqueline Lee A96517-2 MSR158-4 MSM171-A MSQ440-2 MSM224-1 RB Spunta/CSPAG.13 MSN105-1 LSD0.05 1 Ratings indicate the average plot RAUDPC (Relative Area Under the Disease Progress Curve). 2 147 potato varieties and advanced breeding lines were tested in all. For brevity purposes, only selected varieties and breeding lines are listed. Phytopthora infestans isolates US-1 (Pi 95-3); US-6 (Pi 95-2); US-8 (Pi 02-007); US-10 (SR83-84); US-11 (Pi 96-1); US-14 (Pi 98-1, Pi 99-2) were inoculated on 7/27/07. Planted as a randomized complete block design consisting of 3 replications of 4 hill plots on 6/11/2007. 22.2 23.1 28.0 28.2 29.5 29.9 30.0 30.1 32.3 33.2 33.4 33.8 33.8 34.5 34.6 34.6 35.4 35.5 35.6 35.6 35.7 36.0 36.1 36.3 37.2 37.3 37.7 38.1 38.3 39.6 40.1 41.0 41.2 42.4 42.8 43.7 43.8 MSJ461-1 MSJ461-1 MSH098-2 MSJ461-1 MSJ126-9Y MSJ126-9Y MSE221-1 MSJ461-1 J. Lee MSG227-2 Chaleur J. Lee Norland MSG274-3 NY121 A91194-4 S. microdontum S. microdontum J. Lee 51 Table 13 Entry Atlantic Boulder FL1879 MSH228-6 MSI005-2 MSJ036-A MSJ316-A MSJ461-1 MSK061-4 MSK409-1 MSK498-1 MSM171-A MSN105-1 MSQ176-5 MSQ441-6 R.Norkotah 2007 POTATO EARLY DIE TRIAL MONTCALM RESEARCH FARM May 18 to September 26, 2007 (132 days) MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS USNo1 (cwt/a) Fumigated Non-fumigated lsmean lsmean 182 362 255 257 275 317 218 301 233 195 344 307 219 164 219 250 122 242 214 260 247 235 215 270 152 150 230 256 177 147 162 139 P<0.05 * * * * * Yld Advantage Yld Advantage USNo1 (cwt/a) USNo1 (%) Total (cwt/a) Fumigated Non-fumigated lsmean lsmean 60 120 41 -2 28 83 2 31 80 45 115 51 43 18 57 111 49 50 19 -1 11 35 1 12 53 30 50 20 24 12 35 79 199 385 263 278 292 339 232 330 248 219 359 320 238 170 229 332 133 256 228 281 277 248 227 297 166 170 249 273 194 152 172 213 P<0.05 * * * * * * Yields were significantly different (a = 0.05), demonstrating a significant difference for yield between funigated and non-funigated plots 52 Table 14 MICHIGAN STATE UNIVERSITY POTATO BREEDING and GENETICS 2007 BLACKSPOT BRUISE SUSCEPTIBILITY TEST SIMULATED BRUISE SAMPLES* NUMBER OF SPOTS PER TUBER 1 0 ENTRY 2 DATE OF HARVEST: LATE HARVEST 2 MSJ126-9Y MSN105-1 0 4 FL2101 2 MSK061-4 Pike 7 5 MSH228-6 3 MSJ147-1 3 MSJ316-A MSN191-2Y 4 4 MSM171-A 8 FL2053 MSJ036-A 4 5 FL1879 5 MSK409-1 8 Snowden Beacon Chipper 7 4 Atlantic 21 21 16 16 13 12 16 13 14 12 10 13 8 7 9 5 2 2 3 5 6 5 7 2 7 5 7 6 3 7 8 3 2 7 3 1 1 1 4 1 1 2 1 4 4 4 3 6 6 ADAPTATION TRIAL, CHIP-PROCESSING LINES MSM102-A MSQ089-1 MSN099-B MSN238-A MSQ492-2 MSN190-2 MSM060-3 MSL268-D MSM246-B Pike MSQ029-1 MSL292-A MSN313-A MSQ108-1 Atlantic MSJ461-1 19 18 14 14 12 16 12 7 8 6 12 0 6 6 7 5 4 5 8 9 9 3 5 9 9 9 1 15 8 6 5 10 2 2 3 1 3 2 4 8 5 4 4 6 1 6 6 4 0 1 2 2 1 3 4 5 3 9 5 4 2 4 5+ 1 1 1 1 1 0 3 2 1 1 2 2 2 0 1 2 2 0 2 2 4 1 1 1 1 4 PERCENT (%) BRUISE FREE AVERAGE SPOTS/TUBER 84 84 64 64 52 48 64 52 56 48 40 52 32 28 36 20 8 76 72 56 56 48 64 48 28 32 24 48 0 24 24 28 20 0.2 0.2 0.5 0.5 0.8 0.8 0.8 0.8 0.8 0.8 1.0 1.1 1.3 1.4 1.5 2.2 2.4 0.3 0.4 0.6 0.6 0.7 0.9 1.1 1.1 1.1 1.5 1.5 1.6 1.6 1.6 1.7 1.8 53 2007 BLACKSPOT BRUISE SUSCEPTIBILITY TEST SIMULATED BRUISE SAMPLES* NUMBER OF SPOTS PER TUBER ENTRY MSQ070-1 MSP516-A Snowden 0 8 7 2 1 4 2 6 2 4 6 4 3 4 6 6 ADAPTATION TRIAL, TABLESTOCK LINES MSQ440-2 MSL106-AY MSL183-AY MSM137-2 Yukon Gold MSQ425-4Y MSQ176-5 MSM182-1 MSK498-1Y Boulder Jacqueline Lee MSN170-A MSM070-1 22 21 21 21 21 17 16 14 15 11 6 6 6 1 1 1 1 0 3 3 3 2 2 9 7 6 2 3 3 3 3 5 6 6 5 7 7 6 6 2 2 4 2 5 6 1 4 3 4 1 1 1 0 1 0 0 1 PRELIMINARY TRIAL, CHIP-PROCESSING LINES MSN073-2 ND6095-1 MSP292-7 MSQ130-4 MSR036-5 MSR159-19 ND7519-1 MSP497-1 MSR159-06 MSR128-4Y MSQ134-5 MSR130-1 MSR159-07Y MSQ035-3 MSR102-3 MSR131-5 MSR061-1 MSR049-4 MSR156-7 20 21 19 19 18 18 17 19 18 17 17 16 13 14 12 14 16 14 14 5 3 5 4 5 6 6 4 4 5 6 6 10 7 9 6 3 3 3 0 1 2 2 0 2 1 3 3 0 2 2 2 4 3 4 4 5 2 1 4 2 2 1 0 2 1 1 0 1 5+ 2 6 1 1 1 PERCENT (%) BRUISE FREE AVERAGE SPOTS/TUBER 32 28 8 88 84 84 84 84 68 64 56 60 44 24 24 24 80 84 76 76 72 72 68 76 72 68 68 64 52 56 48 56 64 56 56 1.8 1.9 2.6 0.2 0.2 0.2 0.2 0.2 0.4 0.5 0.7 0.8 1.1 1.4 1.6 1.6 0.2 0.3 0.3 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.5 0.5 0.6 0.7 0.7 0.7 0.8 0.9 0.9 54 2007 BLACKSPOT BRUISE SUSCEPTIBILITY TEST SIMULATED BRUISE SAMPLES* ENTRY MSR167-3Y MSP408-10Y MSN148-A MSP459-5 MSR090-1Y MSR041-5 MSQ341-BY MSR159-10 MSR125-1 ND8305-1 MSM205-A MSR089-14Y MSR160-2Y MSR127-2 Snowden MSP115-3 NUMBER OF SPOTS PER TUBER 0 13 10 11 14 12 6 14 9 7 7 8 10 9 7 6 6 1 3 1 6 4 5 6 4 4 9 4 4 2 3 1 3 2 2 7 4 4 2 5 4 1 7 3 3 7 4 3 6 3 3 3 2 2 3 3 1 4 1 4 4 5 5 3 4 6 6 3 4 1 1 0 1 1 1 2 1 1 3 3 2 4 4 5+ 2 1 4 3 3 3 3 7 PRELIMINARY TRIAL, TABLESTOCK LINES MSR159-2 Esco MSM288-2Y MSP197-1 Caren MSQ437-2PP MSR214-2P Eden MSR186-3P Ronn BP-1 MSQ279-1 MSS582-1 Mnandi MSR157-1Y MSR605-15 Van der Plank MI Purple Red Sport MSQ443-1RR MSR217-1R MSQ461-2PP 23 22 22 22 21 21 21 21 20 22 20 21 20 19 19 18 20 15 17 16 18 2 3 3 3 4 4 4 3 5 1 4 2 4 5 3 5 2 10 7 8 3 1 2 1 1 0 0 3 2 2 0 1 4 1 1 1 1 1 PERCENT (%) BRUISE FREE AVERAGE SPOTS/TUBER 52 56 44 56 48 30 56 36 28 35 32 40 36 28 24 24 92 88 88 88 84 84 84 84 80 88 80 84 80 76 76 72 80 60 68 64 72 0.9 1.1 1.1 1.1 1.1 1.3 1.3 1.4 1.4 1.5 1.5 1.8 1.9 2.2 2.3 2.7 0.1 0.1 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.3 0.3 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.4 55 2007 BLACKSPOT BRUISE SUSCEPTIBILITY TEST SIMULATED BRUISE SAMPLES* NUMBER OF SPOTS PER TUBER ENTRY Calibra MSM224-1 Devlin MSQ505-4 MSR051-1 MSR161-2 MSP084-3 Reba MSQ086-3 MSQ558-2RR Darius MSR081-14 MSM183-1 NY121 MSR158-4 0 18 15 14 17 14 13 16 14 14 7 9 10 7 7 1 ROUND-WHITE TRIAL W2978-3 MSJ316-A CO96141-4W CO97065-7W W2310-3 MSI005-20Y CO97043-14W CO95051-7W NorValley Atlantic W4016-4 W2324-1 NY139 W2564-2 W2133-1 Snowden AC97097-14W 21 19 19 18 16 17 13 15 9 10 10 9 6 9 7 4 3 1 4 7 8 5 6 6 5 7 4 15 9 5 8 8 5 4 5 4 4 7 4 8 5 12 7 6 6 8 5 6 7 3 2 1 3 3 1 4 6 1 1 4 3 6 8 9 5 2 1 2 2 2 2 3 4 4 2 5 7 7 3 6 10 7 3 2 1 1 1 2 3 1 2 1 3 9 1 1 1 0 6 3 2 3 6 4 3 8 4 0 1 0 1 4 1 0 1 1 0 1 1 0 1 5+ 1 1 1 1 4 1 1 1 1 1 3 PERCENT (%) BRUISE FREE AVERAGE SPOTS/TUBER 72 60 56 68 56 52 64 56 56 28 36 40 28 28 4 84 76 76 72 64 68 52 60 36 40 40 36 24 36 28 16 12 0.5 0.5 0.6 0.6 0.7 0.7 0.8 0.8 0.8 0.8 1.0 1.1 1.2 1.4 2.9 0.2 0.3 0.3 0.4 0.4 0.6 0.7 0.7 0.8 1.2 1.2 1.2 1.4 1.5 1.6 1.6 2.4 56 2007 BLACKSPOT BRUISE SUSCEPTIBILITY TEST SIMULATED BRUISE SAMPLES* NUMBER OF SPOTS PER TUBER 4 5+ 1 1 1 1 2 1 2 1 2 1 1 3 3 2 5 2 5 3 5 5 5 3 5 7 1 2 3 4 2 4 3 3 3 2 1 1 1 2 1 1 3 2 2 3 1 6 1 ENTRY RUSSET TRIAL Russet Norkotah MSA8254-2BRUS CO95086-8RUS AND98324-1RUS CO97087-2RUS W5716-1RUS CORN-8 A93157-6LS A95109-1 W3328-1RUS Russet Burbank AOA95154-1 ND7882B-7RUS W1879-1RUS CORN-3 MSL794-BRUS W2683-2RUS Canela RED TRIAL MSQ441-6R ND4659-5R W2609-1R W3882-1R Red Norland Michigan Purple ND5002-3R Rio Colorado MSL228-1 ATND98459-1RY Red Pontiac TRANSGENIC TRIAL MSR606-06 MSR605-07 MSR605-14 MSR606-05 MSR606-09 0 24 21 18 19 14 14 17 15 15 14 13 10 15 10 8 7 6 5 21 21 21 18 17 16 16 13 14 12 14 25 24 24 12 23 1 1 3 5 3 10 8 3 6 4 7 6 11 2 8 10 11 11 5 4 4 4 6 6 6 5 10 7 10 7 1 1 1 2 PERCENT (%) BRUISE FREE AVERAGE SPOTS/TUBER 96 84 72 76 56 56 68 60 60 56 52 40 60 40 32 28 24 20 84 84 84 72 68 64 64 52 56 48 56 100 96 96 92 92 0.0 0.2 0.4 0.4 0.5 0.6 0.6 0.7 0.7 0.7 0.8 0.8 0.8 1.0 1.0 1.2 1.3 1.8 0.2 0.2 0.2 0.3 0.4 0.5 0.5 0.6 0.6 0.6 0.6 0.0 0.0 0.0 0.1 0.1 57 2007 BLACKSPOT BRUISE SUSCEPTIBILITY TEST SIMULATED BRUISE SAMPLES* NUMBER OF SPOTS PER TUBER ENTRY YG8.8 MSR605-05 MSR605-01 MSR605-10 MSR606-02 MSR606-03 NO8.28 MSR606-10 MSR605-04 NO8.8 MSR606-08 MSR605-08 MSR605-17 MSJ036-A 0 22 21 23 20 19 20 20 8 6 17 17 18 11 5 1 2 3 0 4 5 4 2 2 1 6 6 5 7 11 2 1 1 1 1 1 0 2 1 1 2 2 1 2 9 3 0 1 1 0 4 USPB/SFA TRIAL CHECK SAMPLES (Not bruised) CO95051-7W MSJ316-A Snowden MSJ147-1 W2324-1 CO96141-7W Atlantic Beacon Chipper W2133-1 25 25 25 23 23 23 22 18 19 2 2 1 0 7 2 1 2 1 2 2 USPB/SFA TRIAL BRUISE SAMPLES CO96141-7W MSJ147-1 MSJ316-A Atlantic W2324-1 CO95051-7W Snowden W2133-1 Beacon Chipper 4 5 5 6 5 9 8 11 10 19 18 18 17 15 13 12 10 4 1 2 2 2 5 2 4 4 6 1 1 1 4 5+ 1 4 1 0 1 1 PERCENT (%) BRUISE FREE AVERAGE SPOTS/TUBER 88 84 92 80 76 80 80 73 75 68 68 72 44 20 100 100 100 92 92 92 88 72 76 76 72 72 68 60 52 48 40 16 0.2 0.2 0.2 0.2 0.3 0.3 0.4 0.4 0.4 0.4 0.4 0.5 1.1 1.2 0.0 0.0 0.0 0.1 0.1 0.1 0.3 0.3 0.5 0.4 0.4 0.4 0.4 0.6 0.6 0.8 0.8 1.5 * Twenty or twenty-five A-size tuber samples were collected at harvest, held at 50 F at least 12 hours, and placed in a six-s plywood drum and rotated ten times to produce simulated bruising. Samples were abrasive-peeled and scored 11/8/07. The table is presented in ascending order of average number of spots per tuber. 58 Funding: Federal Grant, MPIC and USPB/SFA 2007 On-Farm Potato Variety Trials Chris Long, Dr. Dave Douches, Fred Springborn (Montcalm), Dave Glenn (Presque Isle), Dr. Doo-Hong Min and Chris Kapp (Upper Peninsula) Introduction On-farm potato variety trials were conducted with 12 growers in 2007 at a total of 18 locations. Ten of the locations evaluated processing entries and eight evaluated fresh market entries. The processing cooperators were Crooks Farms, Inc. (Montcalm), Walther Farms, Inc. (St. Joseph), Lennard Ag. Co. (Monroe), 4-L Farms, Inc. (Allegan), Main Farms (Montcalm) and Sackett Potatoes (Mecosta). The United States Potato Board/Snack Food Association (USPB / SFA) chip trial was at Sandyland Farms, LLC (Montcalm). Fresh market trial cooperators were Crawford Farms, Inc. (Montcalm), DuRussel’s Potato Farms, Inc. (Washtenaw), R & E Farms (Presque Isle), Horkey Bros. (Monroe), TJJ VanDamme Farms (Delta), Lennard Ag. Co. (St. Joseph), Sandyland Farms, LLC. (Montcalm) and Walther Farms, Inc. (St. Joseph). Procedure There were five types of processing trials conducted this year. The first type contained 20 entries which were compared with the check varieties Snowden, Pike and FL1879. This trial type was conducted at Main Farms, Lennard Ag. Co. and 4-L Farms. Varieties in these trials were planted in 100’ strip plots. Seed spacing was grower dependent, but in general ranged from 8 to 11 inches. The second type of processing trial, referred to as a “Select” trial, contained from four to nine lines which were compared to the variety in the field. In these trials each variety was planted in a 15’ row plot. Seed spacing and row width was 10” and 34”, respectively. These trials were conducted on Crooks Farms, Inc. The third processing trial format was conducted at Sackett Potatoes in Mecosta County. Two varieties were commercially planted in two separate four row blocks. The rows were 500’ long by 32” wide. Three 23’ yield digs were performed in each block at harvest. These varieties were planted at 10”spacings. The fourth was a four replication processing variety trial conducted at Walther Farms, Inc. in which 22 test varieties were compared to the check varieties FL1867 and FL1879. The plots were 17.5’ by 34” and the seed was planted at 10 inches. The USPB / SFA trial was the 5th chip processing trial type. For procedural details on this trial reference the 2007 annual report published by the United States Potato Board. Within the fresh market trials, there were 34 entries evaluated. There were 5 to 21 lines planted at each of the following locations: Branch, Delta, Monroe, Montcalm, Presque Isle, St. Joseph, and Washtenaw counties. The varieties in each trial ranged from mostly round white varieties to mostly russet varieties. These varieties were planted in 100’ strip plots. Seed spacing varied from 8 to 12 inches depending upon grower production practices and variety. At Walther Farms, Inc (St. Joseph), a four replication trial was evaluated. The plots were 23’ long by 34” wide and seed spacing was 12”. 59 Results A. Processing and “Select” Processing Variety Trial Results A description of the processing varieties, their pedigree and scab ratings are listed in Table 1. The overall averages of the three locations of Allegan, Montcalm and Monroe counties are shown in Table 2. The overall averages of the “Select” processing trial, which are averaged across five locations, are in Table 3. Table 4 contains the date from the Sackett Potatoes variety trial. The data from Walther Farms, Inc. in St. Joseph County is in Table 5. Processing Variety Highlights W2324-1; this clone was developed at the University of Wisconsin and has excellent yield potential. In 2007, W2324-1 was the top yielding variety in 3 of four trials averaging over 470 cwt/A US#1 (Table 2). This variety was susceptible to common scab and had hollow heart in 20% of the oversize tubers (Table 3). In the 2007 USPB/SFA trial, this clone yielded 564 cwt/A US#1 (Table 6). The size profile was good and the specific gravity was above average. The tuber type was marginal and internal defects were higher than desired. Beacon Chipper; this variety continues to exhibit a strong yield performance and size profile. In 2007, Beacon Chipper was the highest yielding line at 585 cwt/A US#1 in the USPB / SFA Variety Trial (Table 6). Beacon Chipper also performed well in the Walther Farms trial at 375cwt/A yield of US#1 size tubers (Table 5). The specific gravity for this clone was generally average. Tuber type was excellent, with moderate scab tolerance and a small amount of internal defects. This variety again had good storage chip quality in mid-February when stored at 50 ºF. Processor response to this variety has been good, but some negative comments have been made regarding the high percentage of oversize tubers. Monticello; this variety had a three year average yield of 360 cwt/A US#1 (Table 2). Chip and internal quality was good. Monticello set 10-12 tubers per plant and had a specific gravity below average (Table 5). The general size profile of this variety was small with only a very small percentage of oversize tubers recorded in 2007. Monticello exhibited the ability to store well into May and June. MSJ036-A (Kalkaska); this Michigan State University developed clone had above average yield of uniform round tubers (Table 3) and excellent resistance to common scab. MSJ036-A has a three year average yield of 387 cwt/A US#1 with an average specific gravity (Table 2). Vine vigor was excellent with some resistance to early die. This variety exhibited a short term storage profile and can be stored until January. W2133-1; this University of Wisconsin developed variety performed well at 408 cwt/A US#1 (Table 2). W2133-1 has had good chip quality across trial locations. This variety has shown variable agronomic performance and virus susceptibility and is slated to be dropped in 2008. 60 B. USPB / SFA Chip Trial Results The Michigan location of the USPB / SFA chip trial was on Sandyland Farms, LLC in Montcalm County in 2007. Table 6 shows the yield, size distribution and specific gravity of the entries when compared with Atlantic and Snowden. Table 7 shows the at harvest raw tuber quality results. Table 8 shows the out of the field chip quality evaluations from samples processed and scored by Herr Foods, Inc., Nottingham, PA and Table 9 provides the blackspot bruise susceptibility of each entry. Tables 10 and 11 provide pre-harvest panels for each of the nine varieties in the trial. They compare tuber specific gravity, percent glucose and sucrose ratings on two different dates. USPB / SFA Chip Trial Highlights The varieties in the 2007 trial that displayed the greatest potential for commercialization were Beacon Chipper, W2324-1 and W2133-1. Yield potential and specific gravity were excellent for W2324-1 (Table 6). Beacon Chipper had the top yield but average specific gravity (Table 6). Beacon Chipper had a slight amount of hollow heart recorded (Table 7). W2133-1 had an average yield performance, but tuber and chip quality were very good (Tables 7, 8,9). MSJ147-1 exhibited excellent long-term storage quality. MSJ147-1 displayed the best post harvest chip quality at Herr Foods (Table 8) and was among the top four varieties with the least amount of black spot bruising (Table 9). MSN105-1; this is a new, very promising, selection for the Michigan State University potato breeding program. This variety had an average yield of 334 cwt/A US#1 (Table 13). This clone had foliar late blight resistance, common scab tolerance and an excellent bright appearance. Rio Colorado; a Colorado State selection had above average yield of 413 cwt/A US#1 with excellent red skin color (Table 13). The variety had a very attractive smooth skin with a round to oval tuber appearance. Internal quality was good and specific gravity averaged 1.069. C. Fresh Market and Variety Trial Results A description of the fresh pack varieties, their pedigree and scab ratings are listed in Table 12. Table 13 shows the overall average of eight locations: Branch, Delta, Monroe, Montcalm (2), Presque Isle, St. Joseph and Washtenaw counties. Fresh Market Variety Highlights One round white, one red skin and five russet lines are worthy of mention from the 2007 variety trials. They are MSN105-1 (the round white), Rio Colorado (the red variety) and the russets, W3328-1Rus, Freedom Russet, CO95086-8Rus, Corn #8 and Canela. 61 W3328-1Rus; this University of Wisconsin variety was the top yielding russet in 2007 at 463 cwt/A US#1 with 30 percent oversize and no hollow heart found in 30 cut tubers (Table 13). The specific gravity was 1.072 with no internal defects noted. Freedom Russet (W1836-3Rus); this University of Wisconsin selection was at eight locations this season (Table 13). The variety has a very full season maturity, possibly 140 days. The US#1 yield was excellent at 416 cwt/A (Table 13). Six percent hollow heart was recorded with a 1.071 specific gravity. This variety does not generally have a very consistent type. CO95086-8Rus; this variety continues to perform better than standard Norkotah, with a 356 cwt/A US#1 yield and average specific gravity (Table 13). Tuber type was blocky with a nice skin type. There are concerns this variety masks PVY. This issue alone will prevent this variety from moving forward. Corn #8; this variety performs better than the stand Norkotah in Michigan (Table 13). The tuber type for this variety was better than the Corn #3. Yield, appearance and internal quality are good. Canela (AC92009); this variety from the Colorado State University breeding program yielded 335 cwt/A US#1 with an above average specific gravity (Table 13). The variety has been noted to have some hollow heart, but skin type and overall appearance was good. 62 Table 1. 2007 MSU Processing Potato Variety Trials Entry Pedigree Atlantic (B6987-56) Wauseon X Lenape Beacon Chipper (UEC) MegaChip (W1201) Monticello (NY102 or K9-29) Pike (NYE55-35) Snowden (W855) AC97097-14W Unknown Wischip X FYF 85 Steuben X Kanona Allegany X Atlantic B5141-6 X Wischip Brodick X A91746-8 CO95051-7W AC88456-6W X BC0894-2W CO96141-4W BC0894-2 X AC87340-2 CO97043- 14W AC91817-5 X AC87340-2 2007 Scab Rating* Characteristics 2.4 1.8 - - 1.8 2.6 3.3 1.5 2.3 3.0 High yield, early maturing, high incidence of internal defects, check variety, high specific gravity High yield, mid-season maturity, some heat stress, good internal quality, scab tolerance, medium low specific gravity High yield, medium to late maturity, slight deep eyes, early bulking, sticky stolon early out of the field, strong vine vigor, high specific gravity Average yield, Mid to late season maturity, good long term storability, low internal defects, vine rot susceptible, medium specific gravity Average yield, early to mid-season maturity, small size tuber profile, early storage check variety, some internal defects, medium specific gravity High yield, late maturity, late season storage check variety, reconditions well in storage, medium to high specific gravity Average yield, mid-season maturity, medium – small size, oblong tuber type, white skin, medium specific gravity Low – average yield, medium to late maturity, high percent of US#1 tubers, low internal defects, medium specific gravity Average yield, early – mid maturity, oval tuber type, white skin, medium specific gravity Average to high yield, medium maturity, white skin, oblong tuber type, medium specific gravity *Scab rating based on 0-5 scale; 0 = most resistant and 5 = most susceptible. 63 Table 1 continued. Entry Pedigree CO97065-7W FL1867 FL1879 FL1922 FL2053 AC92513-3 X Chipeta FL 162 x ATLANTIC Snowden X FL 1207 FL1533 X FL1207 FL1922 X ‘FL1831 MSH228-6 MSC127-3 OP MSJ036-A A7961-1 X Zarevo MSJ126-9Y Penta OP MSJ147-1 MSJ316-A MSK061-4 Norvalley X S440 Pike X MSB0718-3 MSC148-A X Dakota Pearl 2007 Scab Rating* Characteristics 2.0 - 2.0 - 1.8 1.8 0.8 1.3 1.0 1.9 1.0 Average to high yield, early maturity, white skin, round tuber type, medium specific gravity High yield, early maturity, medium-high specific gravity High yield, late maturity, large tuber type, late season storage, medium specific gravity, check variety Average yield, mid-season maturity, oval to oblong tubers, common scab and black spot bruise resistant, good chip quality out of late storage, medium to low specific gravity Average yield, mid-season maturity, round to oblong tuber type, good bruise tolerance, fresh or early season storage, highly susceptible to growth crack, medium-high specific gravity Average yield, mid-season maturity, blocky flat tuber type, shallow eyes, medium specific gravity Medium – high yield, mid-season maturity, nice round uniform tuber type, warm harvest recommended, medium high specific gravity Medium – high yield, cold chipper from 45º F, uniform A-size tubers, attractive appearance, good internal quality, long term storage potential, low - medium specific gravity Average yield, mid to late season maturity, good internal quality, very good chip quality late in storage, medium specific gravity Medium to high yield, late maturity, some internal defects noted, round tuber type, scab tolerant, good type, medium specific gravity Average yield, mid-season maturity, good chip quality, breaks dormancy easily, sprouts easily, medium specific gravity *Scab rating based on 0-5 scale; 0 = most resistant and 5 = most susceptible 64 Table 1 continued. Entry Pedigree 2007 Scab Rating* Characteristics MSK409-1 MSL007-B MSN191-2Y MSN238-A NY 139 (Y28-9) W2133-1 W2310-3 W2324-1 MSC148-A X Liberator MSA105-1 X MSG227-2 MSI234-6Y X MSH098-2 Marcy X MSH098-2 NY120 X NY115 Snowden X RHL 167 Pike X RHL167 Snowden X RHL166 0.8 - 1.5 1.3 1.5 1.8 2.0 2.5 Medium to high yield, early to mid-season maturity, storage chipper, flat oval tuber type, medium specific gravity Below average yield, early to mid-season maturity, uniform small tuber type, medium specific gravity Below average yield, early to mid-season maturity, small round uniform tuber type, medium – high specific gravity Low to average yield, early – medium vine maturity, medium specific gravity High yield, mid-late season maturity, medium specific gravity Medium to high yield, mid to late maturity, good internal quality, nice tuber type, 42- 45ºF cold chipper, medium specific gravity Below average yield, medium maturity, small round oblong tuber type, medium brown skin, medium to high specific gravity Very high yield, late maturity, uniform tuber type, strong vine vigor, medium to high specific gravity *Scab rating based on 0-5 scale; 0 = most resistant and 5 = most susceptible. 65 Table 2. 2007 Processing Potato Variety Trial Overall Average - Three Locations Allegan, Monroe, Montcalm Counties NUMBER OF LOCATIONS LINE 3 2 3 3 3 3 3 2 3 2 3 2 3 3 3 3 3 3 3 3 3 3 3 W2324-1 W2133-1 FL1879 Snowden Monticello MSJ126-9Y MSK409-1 CO97043-14W Beacon Chipper CO97065-7W MSJ036--A MSH228-6 MSK061-4 CO96141-4W MSN238-A FL2053 AC97097-14W Pike MSJ147-1 W2310-3 CO95051-7W MSL007-B MSN191-2Y MEAN CWT/A US#1 474 408 395 369 358 348 347 337 336 328 325 321 308 302 300 285 269 260 259 257 252 250 248 319 TOTAL US#1 503 438 406 393 397 385 397 364 352 341 373 345 351 334 329 327 314 301 310 295 275 289 292 353 94 92 97 92 89 90 85 93 95 96 87 93 87 90 91 87 83 84 83 86 92 86 85 89 PERCENT OF TOTAL1 OV Bs 5 8 As 86 PO 1 CHIP TUBER QUALITY2 SP GR SCORE3 HH VD IBS BC 1.078 0 1.3 5 13 0 TOTAL CUT 30 VINE MAT4 3.3 8 3 3 7 6 8 7 4 4 9 6 7 8 8 7 7 10 10 9 6 10 11 79 81 81 88 87 79 87 86 89 85 90 82 85 88 85 78 82 79 86 89 86 83 13 16 11 1 3 6 6 9 7 2 3 5 6 4 2 4 1 4 1 2 0 2 0 0 5 4 3 6 0 1 0 4 0 6 2 1 7 10 7 6 5 2 4 5 1.079 1.075 1.074 1.073 1.071 1.077 1.076 1.074 1.078 1.076 1.075 1.078 1.067 1.077 1.082 1.070 1.076 1.080 1.081 1.076 1.073 1.082 1.076 1.0 1.5 1.0 1.3 1.3 1.0 1.0 1.2 1.3 1.0 1.0 1.0 1.0 1.0 1.0 1.2 1.0 1.0 1.0 1.0 1.0 1.2 1.1 0 6 1 3 0 1 2 0 0 1 1 1 0 0 0 1 0 1 0 2 1 0 2 7 12 7 5 10 1 7 3 4 5 22 6 2 3 4 8 3 2 10 3 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 1 0 1 0 0 0 0 0 1 0 0 0 0 0 0 4 0 0 0 1 0 0 20 30 30 30 30 30 20 30 20 30 20 30 30 30 30 30 30 30 30 30 30 30 2.5 1.0 1.8 2.3 1.8 1.0 2.0 2.8 1.0 3.3 3.0 2.5 1.5 1.8 1.5 1.5 1.5 2.0 1.8 2.3 2.0 1.5 2.0 1SIZE Bs: < 1 7/8" 2TUBER QUALITY (number of tubers per total cut) HH: Hollow Heart 3CHIP COLOR SCORE - Snack Food Association Scale (Out of the field) As: 1 7/8" - 3.25" VD: Vascular Discoloration OV: > 3.25" IBS: Internal Brown Spot PO: Pick outs BC: Brown Center Ratings: 1 - 5 1: Excellent 5: Poor 4 MATURITY RATING Date Taken: 18-Sept-07 Ratings: 1 - 5 1: Early (Vines Completely Dead) 5: Late (vigorous vine, some flowering) 3-YR AVG US#1 CWT/A - - 384 429 360 - - - 381 - 387 379 354 - - - - 320 323 - - - - COMMENTS pitted scab, sticky stolon, rough type surface & raised scab surface & pitted scab, growth cracks, large type sl pitted scab small bright round tuber type, tr pitted scab netted skin, round uniform type flat oval type, tr surface scab tr pitted scab, flat round type sl surface scab, large type uniform round type nice uniform round type blocky flat type heat sprouts, vascular discoloration sl surface & pitted scab, SED small round type, tr pitted scab growth cracks, sl pitted scab oval to oblong type, internal heat necrosis noted tr surface scab, small bright round type bright uniform round type, tr pitted scab tr surface & pitted scab surface scab, sticky stolon heavy netted skin, uniform type small round uniform type, sl pitted scab, yellow flesh tr = trace, sl = slight, NA = not applicable SED = stem end defect 66 Table 3. 2007 "Select" Processing Potato Variety Trial Overall Average - Crooks Farms, Inc., Five Locations (Montcalm County): Eply, Holland, Klees, Nevins & Waterwheel Roads NUMBER OF LOCATIONS 2 5 2 2 5 5 2 1 2 2 2 LINE W2324-1 MSJ036-A (Utz) MSK061-4 Snowden MSJ036-A (Herr) MSJ036-A (Crooks) Pike FL1867 MSJ126-9Y MSJ147-1 W2310-3 1SIZE Bs: < 1 7/8" MEAN CWT/A US#1 905 490 477 477 460 433 341 313 280 279 255 428 TOTAL US#1 946 557 513 503 524 504 374 355 328 348 298 477 95 87 93 96 87 85 91 88 85 80 86 88 PERCENT OF TOTAL1 Bs OV 31 4 As 64 PO 1 CHIP SP GR SCORE3 1.085 1.0 TUBER QUALITY2 VD 2 IBS 1 HH 4 BC 0 TOTAL CUT 20 VINE MAT4 2.0 pitted scab COMMENTS 13 7 4 13 15 9 12 15 19 14 83 85 74 82 81 89 86 83 77 82 4 8 22 5 4 2 2 2 3 4 0 0 0 0 0 0 0 0 1 0 1.080 1.078 1.082 1.081 1.080 1.077 1.081 1.067 1.085 1.079 1.080 1.3 1.0 1.8 1.2 1.3 1.0 1.0 1.3 1.0 1.5 1.2 1 0 7 0 1 0 0 0 0 0 3 9 7 3 7 0 0 1 2 1 3 0 1 3 5 0 0 0 0 0 0 0 2 3 0 0 0 0 0 0 50 20 20 50 50 20 10 20 20 20 3.2 1.5 3.5 3.2 3.2 3.0 2.0 1.5 2.0 1.5 2.4 uniform round type, SED & IBS noted round to oval type tr heat necrosis noted uniform round type, tr IBS, uniform round type, good size, vascular discoloration noted, tr IBS small uniform type tr pitted scab small size, yellow flesh tr surface scab, oval to round type small flat round type tr = trace, sl = slight, NA = not applicable SED = stem end defect 2TUBER QUALITY (number of tubers per total cut) 3CHIP COLOR SCORE - Snack Food Association Scale HH: Hollow Heart As: 1 7/8" - 3.25" VD: Vascular Discoloration OV: > 3.25" PO: Pick outs IBS: Internal Brown Spot BC: Brown Center (Out of the field) Ratings: 1 - 5 1: Excellent 5: Poor 4Vine Maturity Rating Date taken: Ratings 1-5 1: Early (vines completely dead) 5: Late (vigorous vine, some flowering) 67 Table 4. CWT/A LINE MSK061-4(3) MSK061-4(2) MSK061-4(1) MSJ316-A(3) MSJ316-A(1) MSJ316-A(2) US#1 416 411 407 411 486 464 420 456 MEAN MEAN TOTAL US#1 467 445 440 451 515 509 459 494 90 93 92 92 94 91 91 92 2007 Processing Potato Variety Trial Sackett Potatoes - Mecosta County Harvest 10-Oct-07 DD, Base 405 145 Days 3361 PERCENT OF TOTAL1 OV Bs 9 8 7 7 4 7 3 8 10 As 82 86 88 91 83 81 5 7 7 PO 1 0 1 1 2 2 1.080 1.078 CHIP SP GR SCORE3 TUBER QUALITY2 VD 3 2 3 IBS 0 0 0 HH 0 0 1 BC 0 0 1 TOTAL CUT 10 10 10 1.0 0.33 2.67 0.00 0.33 0 0 0 0 5 2 0 1 2 0 4 0 10 10 10 1.0 0.00 2.33 1.00 1.33 VINE MAT4 1.0 3.5 COMMENTS knobs, tr surface scab round, flat, tr surface scab misshapen, 7 heat necrosis sticky stolon, 1 heat necrosis, tr misshapen mostly round, flat, tr surface scab tr = trace, sl = slight, NA = not applicable SED = stem end defect 1SIZE Bs: < 1 7/8" 2TUBER QUALITY (number of tubers per total cut) HH: Hollow Heart 3CHIP COLOR SCORE - Snack Food Association Scale (Out of the field) As: 1 7/8" - 3.25" VD: Vascular Discoloration Ratings: 1 - 5 OV: > 3.25" IBS: Internal Brown Spot 1: Excellent PO: Pick outs BC: Brown Center 5: Poor 4 MATURITY RATING Date Taken: 18-Sept-07 Ratings: 1 - 5 1: Early (Vines Completely Dead) 5: Late (vigorous vine, some flowering) Planted: Vines Killed: Days from Planting to Vine Kill: Seed Spacing : No Fumigation 18-May-07 18-Sep-07 123 10" 5MAWN STATION: Entrican 68 Table 5. LINE F1879 FL1867 Beacon Chipper MSL007-B W2324-1 MSK409-1 W2133-1 CO97065-7W FL2053 Monticello MegaChip MSJ126-9Y MSH228-6 CO95051-7W AC97097-14W W2310-3 CO96141-4W FL1922 CO97043-14W MSJ036-A MSN191-2Y MSJ147-1 MSK061-4 MSN238-A MEAN 1SIZE Bs: < 2" As: 2 - 3 1/2" OV: > 3 1/2" PO: Pickouts 2007 Processing Potato Variety Trial Walther Farms - St. Joseph County 128 Days 3345 Harvest: 20-Sep-07 DD, Base 405 US# 1 Yield in CWT/A 421 Total Yield in CWT/A 430 US#1 98 PERCENT OF TOTAL1 Bs OV 0 2 As 98 CHIP SP GR SCORE3 1.078 1.0 HH 7 TUBER QUALITY2 VD 0 IBS 0 BC 0 TOTAL CUT 20 PO 0 380 375 324 323 318 311 308 281 280 280 270 264 263 257 257 256 253 249 248 244 220 213 206 283 406 408 370 378 360 369 339 379 327 344 305 295 325 297 295 332 319 282 295 294 308 279 276 334 93 92 88 85 88 85 91 74 86 81 89 90 81 87 87 77 79 89 84 83 71 76 75 85 4 3 8 4 8 7 1 3 11 3 8 4 6 5 4 6 12 5 5 13 25 4 3 85 87 88 75 83 82 91 74 86 77 89 84 81 84 87 77 79 89 84 83 69 76 75 8 5 0 10 5 3 0 0 0 4 0 6 0 3 0 0 0 0 0 0 2 0 0 3 5 4 11 4 8 8 23 3 16 3 6 13 8 9 17 9 6 11 4 4 20 22 1.087 1.074 1.073 1.080 1.083 1.080 1.072 1.090 1.075 1.081 1.070 1.078 1.079 1.077 1.084 1.070 1.077 1.073 1.086 1.094 1.076 1.073 1.076 1.079 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.5 1.0 1.0 1.0 1.0 1.0 1.5 1.0 1.0 1.5 1.0 1.0 1.0 1.0 1.1 7 0 6 8 2 0 3 0 2 0 2 1 0 1 2 0 1 3 1 0 1 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 0 0 0 5 0 1 0 2 1 0 1 5 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 COMMENTS pitted scab, pink eye sheep nose greening, misshapen, 2 SED nice type, heavy netting, small pitted scab, sticky stolon, greening, knobs tr pitted scab uniform type growth crack greening, misshapen netted skin tr scab, flat, oval, 3/20 pink eye heat sprouts, 2 blackleg, SED, greening pink eye, oblong, surface & pitted scab, points tr scab greening, tr scab, oblong to oval, flattened poor type, not uniform tr surface scab small, netted skin nice type, heavy netting small type, good appearance, greening, misshapen oval to oblong, tr pitted scab greening, misshapen tr = (trace), sl = (slight), NA = Not applicable SED = stem end defect 2TUBER QUALITY (number of tubers per total cut) HH: Hollow Heart VD: Vascular Discoloration IBS: Internal Brown Spot BC: Brown Center 3CHIP COLOR SCORE - Snack Food Association Scale (Out of the field) Ratings: 1 - 5 1: Excellent 5: Poor Planted: Vines Killed: Days from Planting to Vine Kill: Seed Spacing : 15-May-07 3-Sep-07 111 10" Fumigated 5MAWN STATION: Mendon 69 Table 6. Yield ,Size Distribution*, Specific Gravity Yield (cwt/A) Percent Size Distribution Entry TOTAL Small Mid-Size Large 2 3 3 4 5 5 7 15 29 600 598 501 434 403 385 384 279 259 427 US#1 585 564 487 404 378 366 351 238 184 395 Beacon Chipper W2324-1 Snowden Atlantic W2133-1 CO96141-4W MSJ316-A CO95051-7W MSJ147-1 US#1 97 95 97 93 94 95 92 85 71 91 *small <1 7/8"; mid-size 1 7/8"-3 1/4"; large >3 1/4" Table 7. At Harvest Tuber Quality. Sandyland Farms, Howard City, Michigan. 18 13 16 14 10 3 3 0 0 MEAN Specific Culls Gravity 1.077 1.081 1.078 1.079 1.083 1.067 1.076 1.074 1.085 1.078 1 2 0 3 1 0 1 0 0 79 82 81 79 84 92 89 85 71 IBS 0 0 0 1 0 0 0 0 0 Internal Defects1 Entry Total Cut 30 30 30 30 30 30 30 30 30 1Internal Defects. HH = hollow heart, VD = vascular discoloration, IBS = internal brown spot, BC = brown center. Beacon Chipper W2324-1 Snowden Atlantic W2133-1 CO96141-4W MSJ316-A CO95051-7W MSJ147-1 BC 0 0 1 0 0 0 1 0 0 HH 4 2 5 14 1 0 0 0 0 VD 3 2 5 3 2 4 2 1 0 70 Table 8. 2007 Post-Harvest Chip Quality1. Entry Beacon Chipper W2324-1 Snowden Atlantic W2133-1 CO96141-4W MSJ316-A CO95051-7W MSJ147-1 Agtron Color 68.0 62.9 61.8 63.9 61.4 61.4 64.0 64.0 59.7 SFA2 Specific Color Gravity 1.075 1.078 1.073 1.073 1.078 1.062 1.072 1.074 1.080 1 2 2 2 2 2 2 2 2 Internal External Percent Chip Defects3 Total 14.2 15.4 16.3 34.5 8.6 9.5 8.0 10.0 5.8 10.0 13.9 15.2 12.8 6.4 7.9 3.1 8.2 3.8 4.2 1.5 1.1 21.7 2.2 1.6 4.9 1.2 2.0 1 Samples collected at harvest October 4th and processed by Herr Foods Inc., Nottingham, PA on October 8, 2007 (4 days). Chip defects are included in Agtron and SFA samples. 2 SFA Color: 1 = lightest, 5 = darkest 3 Percent Chip Defects are a percentage by weight of the total sample; comprised of undesirable color, greening, internal defects and external defects. Table 9. Black spot Bruise Test A. Check Samples1 B. Simulated Bruise Samples2 Entry Beacon Chipper W2324-1 Snowden Atlantic W2133-1 CO96141-4W MSJ316-A CO95051-7W MSJ147-1 Total # of Bruises Per Tuber 0 1 2 3 4 5 Tubers 18 7 23 2 25 22 0 2 1 19 2 2 2 23 1 1 25 25 23 2 25 25 25 25 25 25 25 25 25 Percent Average Bruise Bruises Per Free 76 92 100 88 76 92 100 100 92 Tuber 0.3 0.1 0.0 0.3 0.5 0.1 0.0 0.0 0.1 Total # of Bruises Per Tuber 0 1 2 3 4 5 Tubers 4 10 6 4 1 15 5 5 12 8 4 1 17 6 2 10 11 4 19 4 1 1 18 5 2 13 9 2 1 18 5 2 25 25 25 25 25 25 25 25 25 Percent Average Bruise Bruises Per Free 16 60 48 68 40 76 72 52 72 Tuber 1.5 0.6 0.8 0.4 0.8 0.4 0.4 0.6 0.4 1Tuber samples collected at harvest and held at room temperature for later abrasive peeling and scoring. 2Tuber samples collected at harvest, held at 50ºF for at least 12 hours, then placed in a 6 sided plywood drum and rotated 10 times to produce simulated bruising. They were then held at room temperature for later abrasive peeling and scoring. 71 Table 10. Pre-Harvest Panels, 8.9.07 Average5 Entry Beacon Chipper W2324-1 Snowden Atlantic W2133-1 CO96141-4W MSJ316-A CO95051-7W MSJ147-1 % Canopy Number of Specific Glucose1 Sucrose2 Gravity 1.070 1.068 1.068 1.074 1.075 1.069 1.063 1.072 1.067 Tuber Rating Rating3 Uniform.4 Hills Stems Weight 4.68 1.006 2.27 0.568 0.613 2.67 4.02 0.673 3.51 0.497 3.48 0.243 1.860 2.74 2.92 0.514 0.776 1.87 0.004 0.003 0.003 0.002 0.001 0.001 0.014 0.001 0.004 100 100 100 100 90 90 100 90 100 95 95 95 85 80 75 100 80 95 16 10 16 14 14 15 14 19 13 4 2 5 3 4 4 6 5 4 1Percent Glucose is the percent of glucose by weight in a given amount of fresh tuber tissue. 2Sucrose Rating is the percent of sucrose by weight in a given amount of fresh tuber tissue X10. 3 The Canopy Rating is a percent rating of green foliage (0 is all brown dead foliage, 100 is green vigorus foliage). 4 The Canopy Uniformity is a percentage of how uniform the foliage health is at the date of observation. 5 The Average Tuber Weight is the total tuber weight collected divided by the number of tubers reported in ounces. Table 11. Pre-Harvest Panels, 8.21.07 Average5 Entry Beacon Chipper W2324-1 Snowden Atlantic W2133-1 CO96141-4W MSJ316-A CO95051-7W MSJ147-1 % Canopy Number of Specific Glucose1 Sucrose2 Gravity 1.077 1.078 1.079 1.071 1.079 1.069 1.069 1.077 1.080 Tuber Rating Rating3 Uniform.4 Hills Stems Weight 6.37 0.546 4.13 0.462 5.95 0.368 5.23 0.497 0.439 4.32 4.43 0.252 4.77 0.976 3.15 0.409 0.396 2.01 0.002 0.003 0.001 0.002 0.001 0.001 0.006 0.001 0.002 90 85 90 90 85 85 90 90 90 12 16 16 16 20 16 13 15 14 95 90 95 85 75 70 90 95 95 4 3 4 4 5 4 6 4 3 1Percent Glucose is the percent of glucose by weight in a given amount of fresh tuber tissue. 2Sucrose Rating is the percent of sucrose by weight in a given amount of fresh tuber tissue X10. 3 The Canopy Rating is a percent rating of green foliage (0 is all brown dead foliage, 100 is green vigorus foliage). 4 The Canopy Uniformity is a percentage of how uniform the foliage health is at the date of observation. 5 The Average Tuber Weight is the total tuber weight collected divided by the number of tubers reported in ounces. 72 Table 12. 2007 MSU Freshpack Potato Variety Trials Entry Pedigree 2007 Scab Rating* Blazer Russet (A8893-1) A7816-14 X Norking Russet Boulder (MSF373-8) MS702-80 X NY88 Canela (AC92009-4Rus) A83043-12 X A8784-3 Chieftain (Iowa 57410) La1354 X Ia1027-18 Corn #3 Russet Norkotah Line Selection Corn #8 Russet Norkotah Line Selection Dakota Jewel (ND3196-1R) ND2223-8R X ND649-4R Defender (A90586-11) KSA195-90 X Ranger Russet Freedom Russet (W1836-3rus) ND 14-1 Rus X W 1005-Rus Katahdin (USDA42667) USDA40568 X USDA24642 - 1.8 0.3 - 1.5 2.3 - - - - *Scab rating based on a 0-5 rating; 0 = most resistant and 5 = most susceptible. Characteristics High yield, mid-early maturity, oblong russet, medium-to-large tuber size, light netting, brown-to-tan skin, cream- white or white flesh, medium specific gravity, dual purpose High yield, large tuber size, medium specific gravity, low internal defects, med.-deep eyes Average yield, oblong blocky russet, good storability, above average specific gravity High yield, slightly oval - large tuber size, red waxy skin type, low internal defects High yield, large tuber size, mid-season maturity, tubers are white flesh, long to slightly oblong, medium to heavy russetted skin, eyes are shallow, numerous and well distributed tuber set, medium specific gravity Average yield, early to mid-season maturity, tubers are white flesh, long to slightly oblong, medium to heavy russetted skin, eyes are shallow, numerous and well distributed tuber set, medium specific gravity Average yield, early tuber maturity, smooth round tubers, nice red color out of the field, white flesh, shallow apical eyes, stores well, low specific gravity, some brown center noted. Medium to high yield, late maturing, medium to large size, long tuber type, late blight resistant, common scab susceptible, high specific gravity High yield, late vine maturity, long blocky russet tubers, exhibits superior tuber bulking rate when harvested at 120 days, highly resistant to Verticillium wilt, resistant to common scab Medium to high yield, large size, round white tuber type, excellent storability, medium specific gravity, shallow eyes, check variety 73 Table 12 continued. Entry Pedigree Onaway USDA X96-56 X Katahdin Premier Russet (A93157-6LS) A87149-4 X A88108-7 Reba (NY 87) Monona X Allegany Rio Colorado (NDC5281-2R) ND3196-1R X ND2224-5R Russet Norkotah (ND534-4 Rus) ND9526-4 Rus X ND9687-5 Rus Silverton (A83064-6) Vivaldi (VDZ 87-105) A95109-1Rus A76147-2 x A 7875-5 TS 77-148 x Monalisa Blazer Russet X Summit Russet AOA95154-1Rus Bannock Russet X A89152-4 AOTX95265-4Rus A89216-9 x A86102-6 CO95086-8Rus CO87009-4Rus X Silverton Russet CO97087-2Rus CO87009-4 x W1005 2007 Scab Rating* - 1.0 1.8 1.5 2.0 - - 0.7 0.5 - 0.0 0.5 Characteristics High yield, early maturity, round tuber type, low specific gravity, smooth skin, white flesh, eyes medium – deep, few internal defects, check variety Average yield, maintains low levels of reducing sugars even after extended storage, Med to late maturity, dual purpose usage, PVY resistant, high specific gravity High yield, bright tubers, low incidence of internal defects, mid to late season maturity, medium – low specific gravity Medium to high yield, medium maturity, medium tuber size, nice red color, round to oval shape, medium to low specific gravity Average yield, mid-season maturity, long to oval tubers, heavy russet skin, check variety, low specific gravity High yield, oblong to long blocky tuber type, medium russet skin, masks PVY, medium specific gravity High yield, smooth oval buff skinned tuber, light yellow flesh, slightly tolerant to common scab, low specific gravity Below average yield, early maturity, attractive appearance, fresh market use, low - medium specific gravity Medium yield, late maturity, long russetted tubers, high specific gravity, good fry color from storage, High yield, mid-late maturity, oblong to long russetted tubers, generally nice appearance Good market yield, medium maturity, resistant to black spot bruise, little internal defects, good size profile, medium yield potential, dual purpose russet, medium specific gravity, good processing from storage. Average yield, medium maturity, oblong flat russet, medium specific gravity, dual purpose *Scab rating based on a 0-5 rating; 0 = most resistant and 5 = most susceptible. 74 Table 12 continued. Entry Pedigree 2007 Scab Rating* Characteristics MSI005-20Y MSA097-1Y X Penta MSL268-D MSM060-3 MSM171-A NY103 X Jacqueline Lee MSG007-1 X ND2676-10 Stirling X MSE221-1 MSN105-1 MSG141-3 X Jacqueline Lee MWTX2609-4Rus Russet Burbank X Ontario & 4xhybrid TX 112 TX 296 W2609-1R W2683-2Rus W3328-1Rus W3882-1R Russet Norkotah Line Selection Russet Norkotah Line Selection Dark Red Norland X W774R ND4093-4 X CO80011-5 W1099Rus X AC88064-6Ru3 Nordonna X AC88064-6Rus 2.0 1.5 1.8 1.3 2.0 - - - 0.8 0.5 1.0 1.0 High yielding, early to mid-season maturity, low internal defects, strong yellow flesh color Medium yield, late blight resistant, round to oval tuber type Yield similar to Pike, medium specific gravity, scab resistant, round blocky tuber type High yield, late maturity, smooth shape, large round tuber type, superior skin type, late blight resistant, low specific gravity Average yield, early maturity, large heavy set tuber type, bright skin, medium specific gravity, moderate late blight resistance High yield, mid to late maturity, long large tuber type, light russet skin, medium specific gravity Yields higher than standard Norkotah, oblong to long tuber type, smooth medium russet, white flesh, good appearance, earlier maturity, low specific gravity High yields, later maturity than standard Norkotah, heat resistant, low specific gravity Below average yield, early maturity, light red netted skin, small tuber type, low – medium specific gravity High yield, medium to late maturity, oblong to long tuber type, dark brown heavy russet skin, medium low specific gravity High yield, medium to late maturity, oblong to long blocky tuber type, dark brown heavy russet skin, medium low specific gravity Below average yield, medium maturity, uniform round tuber type, netted skin, good red color, low specific gravity *Scab rating based on a 0-5 rating; 0 = most resistant and 5 = most susceptible. 75 Table 13. 2007 Freshpack Potato Variety Trial Overall Averages - Eight Locations Branch, Delta, Monroe, Montcalm (2), Presque Isle, St. Joseph & Washtenaw Counties TUBER QUALITY2 VD 0 IBS 0 BC 0 TOTAL CUT 10 VINE MAT3 4.0 nice yellow flesh COMMENTS 5 0 0 4 6 1 0 0 0 0 1 1 0 3 0 0 0 0 0 0 1 0 0 0 0 0 3 1 0 0 6 1 0 0 1 0 0 1 0 0 0 0 0 0 1 0 0 4 0 0 0 40 10 30 80 10 40 10 30 10 100 10 30 40 40 30 30 10 3.5 NA 4 4 yellow flesh, surface scab, oval to oblong knobs, misshapen, tr pitted scab NA deep apical eye, tr surface scab, bright appearance 4 not uniform type, misshapen NA pitted scab, nice type 3 uniform type NA not uniform type, tr pitted scab tubular type, not very uniform knobs, light red, growth cracks slight surface scab, nice red skin color, round to oval appearance 4 NA 3 3 NA tr scab, uniform, small round type knobs, heat sprouts 4 2 2.5 large percentage of "As" 3-YR AVG US#1 CWT/A 456 - 325* - 418 317* 435 426 445 - - - - - - - - NUMBER OF LOCATIONS LINE 1 3 1 3 6 1 4 1 3 1 8 1 3 2 4 1 1 1 MSI 005-20Y MSM171-A Vivaldi W3328-1Rus Corn #3 Katahdin W2683-2Rus Boulder Reba Onaway Freedom Russet Chieftain Rio Colorado TX 296 MSL268-D MWTX2609-4Rus AOTX95265-4Rus TX 112 CWT/A US#1 599 494 471 463 453 452 438 428 426 418 416 416 413 395 380 378 374 364 TOTAL US#1 633 537 501 516 538 465 531 442 442 439 519 458 469 469 422 631 517 403 95 94 94 89 85 97 82 97 96 95 79 90 87 85 90 60 72 91 PERCENT OF TOTAL1 OV Bs 3 32 As 63 4 6 8 8 3 5 3 3 5 16 4 12 9 8 12 13 9 64 94 59 61 73 46 65 66 82 61 50 81 51 79 44 53 71 30 0 30 24 24 36 32 30 13 18 40 6 34 11 16 19 20 PO 2 2 0 3 7 0 13 0 1 0 5 6 1 6 2 28 15 0 SP GR 1.080 1.061 1.056 1.072 1.073 1.066 1.071 1.073 1.070 1.056 1.071 1.061 1.069 1.065 1.074 NA NA 1.066 continued on next page: HH 0 0 0 0 23 0 3 0 0 0 6 1 0 5 4 4 3 0 76 TOTAL US#1 82 84 87 83 74 72 82 76 95 65 85 82 91 71 86 38 432 404 392 398 444 450 387 402 318 420 346 332 282 361 266 417 441 PERCENT OF TOTAL1 OV Bs 15 18 As 64 PO 3 SP GR 1.069 12 6 16 11 14 12 21 5 14 10 13 7 27 10 54 61 64 79 58 57 64 56 90 57 71 75 89 61 79 38 23 23 4 16 15 18 20 5 8 14 7 2 10 7 0 4 7 1 15 14 6 3 0 21 5 5 2 2 4 8 1.061 1.081 1.074 1.076 1.074 1.065 1.082 1.062 1.044 1.066 1.082 1.066 1.062 1.066 1.068 1.068 LINE CO95086-8Rus US#1 356 341 335 334 326 325 320 312 303 301 297 273 256 256 227 158 367 Corn #8 Canela MSN105-1 A93157-6LS CO97087-2Rus Russet Norkotah AOA95154-1Rus W2609-1R Silverton A95109-1 Rus MSM060-3 W3882-1R Blazer Russet Dakota Jewel Defender MEAN 1SIZE Bs: < 1 7/8" or < 4 oz. 2TUBER QUALITY (number of tubers per total cut) HH: Hollow Heart As: 1 7/8" - 3.25" or 4 - 10 oz. VD: Vascular Discoloration OV: > 3.25" or > 10 oz. IBS: Internal Brown Spot PO: Pick outs BC: Brown Center Table 13 continued. CWT/A NUMBER OF LOCATIONS 7 6 5 6 6 5 6 4 2 2 3 5 3 1 2 1 VINE MAT3 COMMENTS 3-YR AVG US#1 CWT/A nice blocky type, no scab, misshapen pick outs tr pitted scab, misshapen pick outs, generally good appearance misshapen small size, bright appearance, tr scab growth cracks, blocky type, knobs misshapen, generally poor appearance 3 3 4 4 4 3 3 4 NA light red skin color, netted skin, small type 3 NA tr pitted scab, nice blocky type 4 3 tr pitted scab, growth cracks, misshapen pick outs uniform type, netted skin, good red color NA tubular, no scab, heavy russeting, uniform type 2 NA 3.3 good red skin color, uniform round type severe scab tr = trace, sl = slight, NA = not applicable SED = stem end defect 274 - - 343* 312 - 228 - - 331* 260 - - - 227 - * Two-Year Average TUBER QUALITY2 VD 3 IBS 1 BC 0 TOTAL CUT 90 7 4 1 3 2 2 6 0 0 2 1 2 1 1 0 0 0 0 3 0 0 2 0 5 0 3 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 80 70 60 80 70 80 40 20 40 30 50 30 10 20 10 3MATURITY RATING Ratings: 1 - 5 1: Early (Vines Completely Dead) 5: Late (vigorous vine, some flowering) HH 8 0 8 1 27 1 1 3 0 2 2 3 3 6 6 1 77 Darryl Warncke Department of Crop & Soil Sciences Michigan State University Response of potato to phosphorus and AVAIL. 2007 SUMMARY Increasing the amount of P2O5 applied tended to increase total tuber yield and yield of grade A tubers, although the differences were not significant at p<0.05. Manganese was the only element to increase in concentration in the leaf at mid-season in response to P application. P rate did not increase the P concentration in the leaf. The P concentration in the leaf was consistently higher when AVAIL was applied, although the difference was not significant at p<0.05. ………………………… A study was conducted on a Hillsdale-Spinks sandy loam at the Michigan State University Montcalm Potato Research Farm to evaluate the response of potatoes to phosphorus applied without and with AVAIL, a product of Specialty Fertilizer Products, Inc. which is indicated to improve phosphorus availability. The previous crop was alfalfa. It was killed with roundup and plowed in the fall. The initial available nitrogen content of the soil averaged about 25 lb N per acre in the top foot. Soil test values averaged: pH 5.4, P-150 ppm, K-123 ppm with a CEC near 8.7 and organic matter near 1.9%. Potash, 200 lbs K20 per acre, was spread in the spring prior to tilling the soil. The P treatments are indicated in Tables 1 to 3. Phosphorus was supplied as 10-34-0 and was blended with 28-0-0 to supply a constant amount of nitrogen (35 lb/a). The fertilizer was applied in bands 2 inches to each side and slightly below the seed pieces. The plots were two rows 32 inches apart and 50 feet long. Two untreated rows were between the treatment rows. The potatoes (cv. FL 1879) were planted on May 10. Admire, a systemic insecticide, was sprayed over the seed pieces before covering with soil. All rows received a topdress application of 150 lbs N/a as urea just prior to hilling. All treatments were replicated four times. Samples of the youngest fully expanded leaves, including petioles, were collected on July 11 for determination of phosphorus and other elements. Temperatures were well above normal during July and August with rainfall being below normal. The plots were irrigated as needed with a center pivot irrigation system. On September 21 tubers were harvested from 35 feet of each of the two treatment rows. The tubers were washed and graded for size. Specific gravity was determined for the A size tubers, 2 to 3.25 inch. Results: The concentrations of the primary elements in the potato leaves on July 11 are shown in Table 1. Sulfur was the only element to show a significant difference. Potatoes receiving __________________ Use of commercial products does not imply endorsement. 78 no P and no AVAIL had a lower S concentration than potatoes receiving the other treatments. Although the average P concentration in the leaves was consistently higher in the leaves of potatoes receiving the AVAIL, the difference was not statistically significant due to variability. Table 1. Primary element content of potato leaves in relation to phosphorus and AVAIL treatments. AVAIL* Applied N Ca Mg - - - - % - - - - K P S No No No No 4.98 5.13 4.90 5.10 0.24 0.25 0.25 0.25 3.55 2.92 3.08 3.05 1.62 1.74 1.66 1.72 0.74 0.80 0.77 0.76 0.28 0.31 0.30 0.31 Yes Yes Yes Yes Lsd.05 CV, % 5.17 5.11 5.00 5.24 ns 3.6 0.28 0.27 0.27 0.27 ns 10.6 3.19 3.35 2.85 2.69 ns 11.6 1.58 1.63 1.77 1.61 ns 7.1 0.74 0.75 0.85 0.74 ns 9.4 0.32 0.32 0.32 0.31 0.02 4.6 * Product of Specialty Fertilizer Products, Inc. Table 2. Micro-element content of potato leaves in relation to phosphorus and AVAIL treatments. AVAIL* Applied B Fe - - - - % - - - - Mn Cu Zn Phosphate Rate lbs P2O5/a 00 40 80 120 00 40 80 120 Phosphate Rate lbs P2O5/a 00 40 80 120 00 40 80 120 Al 33 44 30 33 31 32 33 35 ns 25.7 40.7 37.2 36.7 42.5 34.0 34.5 33.0 38.7 ns 24.6 115 152 97 125 111 110 104 119 ns 28.5 No No No No 30.2 27.5 27.5 28.0 7.5 8.2 7.5 8.2 201 232 236 314 Yes Yes Yes Yes Lsd.05 CV, % 27.7 29.0 28.5 26.2 ns 10.3 8.7 8.5 8.0 7.0 ns 15.0 194 205 209 306 72 20.7 * Product of Specialty Fertilizer Products, Inc. 79 Concentrations of the micronutrients, except manganese, in the potato leaves were not affected by the various treatments (Table 2). The manganese concentration was higher in potatoes receiving 120 lbs P2O5 per acre, but was unaffected by the other rates of phosphorus. Without AVAIL total tuber yield topped out with 80 lbs P2O5 per acre (Table 3). When AVAIL was included with the P fertilizer the highest total tuber yield was achieved with 120 lbs P2O5 per acre. However, this was not significantly better than the yield with the 80 lbs P2O5 per acre with or without AVAIL. Application of AVAIL at the other phosphorus rates did not improve total tuber yield. Effects of the treatments on yield of tubers 2 to 3.25 inches in diameter (A grade) were similar to those of total tuber yields. Yields of the large (> 3.25 inch) tubers and culls were not related to treatment. Although there were significant differences in cull tubers, there was no consistent relation to treatment. Specific gravity of the tubers was similar across all phosphorus rates and AVAIL treatments. Table 3. Influence of phosphorus rate and AVAIL* on potato (FL 1879) tuber Tuber Yield Specific Total >3.25” A’s B’s Culls Gravity - - - - cwt/a - - - - 9.1 17.4 10.5 22.7 9.6 27.4 11.3 20.5 10.9 23.3 9.2 30.7 11.0 26.6 12.1 22.7 3.5 ns 22.7 22.0 1.073 1.074 1.073 1.073 1.074 1.074 1.074 1.075 ns 0.14 yield and specific gravity. 370 393 415 395 No No No No AVAIL* Applied Phosphate Rate lbs P2O5/a 00 40 80 120 00 40 80 120 * Product of Specialty Fertilizer Products, Inc. 46.3 7.8 99 89 114 107 Yes Yes Yes Yes 384 397 425 458 Lsd.05 CV 104 240 83 277 107 271 109 254 251 268 273 316 ns 22.5 33.5 9.7 80 Evaluation of control release N materials for use in potato production. 2007 Darryl Warncke Department of Crop & Soil Sciences Michigan State University SUMMARY A number of slow or controlled release nitrogen materials were evaluated in comparison with a standard N management program and a planting time only N treatment for potato production. The low N potatoes had a lower N content in the leaves and appeared yellowish throughout much of July and August whereas potatoes receiving adequate N remained green until near senescence. There were no appearance differences among the N sources. Differences in tuber yield were observed only in the 2 to 3½ inch size. Total and U.S. No. 1 tuber yields did not differ among the N sources or N programs. Introduction: This study was conducted to evaluate the use of several controlled-release N products in comparison to a standard nitrogen management program for production of potatoes. The control release/ slow release N products (CRN) were Nitamin 30L, Nitamin GP-43G, Dicyanamide and ESN. The Nitamin materials are products of the Georgia Pacific company and ESN is a product of Agrium. Each of these materials were applied over the row at cracking just prior to cultivation. At planting a 19-17-0 liquid fertilizer was applied in bands 3 inches to sides of the side piece. This supplied 40 lbs N/ acre. Seed pieces of Frito Lay variety 1879, a commonly grown chipping potato, were planted 9 inches apart in rows 32 inches apart. Planting took place on May 10. Admire, a systemic insecticide, was sprayed over the seed pieces before covering with soil. ESN was broadcasted to supply 135 lbs N/ acre just prior to planting. The CRN materials were applied over the row at cracking just prior cultivation to supply 135 lbs N/acre. The standard N management program included, 40 lbs N/acre at planting, 75 lbs N/acre as UAN at cracking and 60 lbs N/acre as Urea at hilling. A summary of the treatments is presented in Table 1. Each of the treatments were replicated four times with a randomized complete block design. Plots were 4 rows 50 feet long. This study was conducted at the Michigan State University Montcalm Research Farm in Montcalm County. It is the main potato research station in Michigan. The research plots were in an area of Hillsdale-Spinks sandy loam soil. The previous crop was alfalfa. It was killed with roundup and plowed in the fall. The initial available nitrogen content of the soil averaged about 25 lb N per acre in the top foot. Soil test values averaged: pH 5.4, P-150 ppm, K-123 ppm with a CEC near 8.7 and organic matter near 1.9 %. Potash, 200 lbs K20 per acre, was spread in the spring prior to tilling the soil. Temperatures were well above normal during July and August with rainfall being below normal. The plots were irrigated as needed with a center pivot irrigation system. Leaf samples (20 per plot) 81 were collected from the two center rows on July 11 to provide a mid-season evaluation of the nitrogen treatments. At harvest on September 21 the two center rows were dug for determination of tuber yield. The tubers were washed and graded according to size. Specific gravity was determined on washed samples. Table 1. Controlled release nitrogen materials, application rates and times used 40 40 40 40 40 40+135-ESN 00 00 zero 75 - UAN 60 135 - Nita.30L 00 135 - GP-43G 00 135 - Dicyan. 00 00 65 200 200 200 200 200 in potato (cv. FL 1879) production study. Timing Primary N Total N1 Planting2 Cracking3 Hilling4 Source - - - - - lb N per acre - - - - - 19-17-0 UAN Nitamin 30L GP-43G Dicyanamide ESN 1 Includes soil N credit of 25 lbs N/acre. 2 Applied as 19-17-0 (liquid) 3 UAN = urea-ammonium nitrate, Nita. 30L = Nitamin 30L, GP-G43 = granular Nitamin, Dicyan.=Dicyandiamide, ESN=ESN. 4 Applied as UAN. Results: Beginning in early July the potatoes receiving only starter nitrogen began to appear lighter green than the rest of the potatoes. On July 26, Potato Field Day, the low N potatoes could easily be distinguished by the yellow color from the other potatoes. No visual differences could be discerned among potatoes receiving the other treatments. On July 11 the total N content of the potato leaves, including petiole, was lower in the potatoes receiving only the 40 lbs N/a at planting time than potatoes receiving 175 lbs N/a (Table 2). Application of adequate N tended to improve P content in the leaves, but there was no difference about N sources. Concentrations of K, Ca, Mg and S in the leaves varied among N sources, but there no one source consistently resulted in higher or lower nutrient concentrations. The same was true with the micronutrient concentrations in the leaves. Boron, Cu and Zn concentrations were relatively consistent among N sources. The unusually high Mn levels probably reflect the spraying of a Mn containing fungicide. Even though the foliage of the low N potatoes had a lower leaf N content and appeared yellowish through much of July and August, the total tuber yield was nearly comparable to potatoes receiving the standard N program or the controlled release N (CRN) materials at 175 lbs supplemental N per acre (Table 4). Significant differences in yield occurred 82 only within the 2 to 3½ inch diameter tubers. Yields of this size tuber were significantly less with GP-43G, Dicyanamide, and ESN than with Nitamin 30L, UAN+urea, or starter N only. Table 2. Total content of N and other selected elements in the youngest fully S % P % K % Ca % N % Mg % developed potato leaves including petiole. July 11. Primary N Source Table 3. Total content of N and other selected elements in the youngest fully starter only UAN Nitamin 30L GP-43G Dicyanamide ESN 1.70 0.75 1.75 0.83 1.63 0.80 1.65 0.78 1.55 0.79 1.76 0.86 3.44 2.72 3.05 3.37 2.99 3.00 6.7 7.7 0.16 0.09 0.27 0.33 0.34 0.29 0.33 0.28 4.43 5.55 5.43 5.37 5.68 5.30 CV Lsd.05 12.3 0.56 10.9 0.5 4.0 0.31 0.34 0.35 0.35 0.33 0.34 0.33 1.0 0.3 Fe ppm Zn ppm B ppm 32 27 27 29 31 29 Cu Mn ppm ppm starter only UAN + Urea Nitamin 30L GP-43G Dicyanamide ESN developed potato leaves including petiole. July 11. Primary N Source Table 4. Effect of N management and control-release N materials on potato (cv. FL 1879) tuber size, yield and specific gravity. Spinks sandy loam. Primary N Non-Starter 8 9 11 9 11 9 39 39 32 39 32 43 Yield 213 325 312 380 206 436 94 155 199 105 118 102 Specific CV Lsd.05 21.0 11.0 24.5 3.6 58.0 102. 21.3 100. 7.1 2.9 83 N Rate Total No. 1 lb/acre - - cwt/ acre - - 2 to 3½ B Size 374 397 401 378 396 360 284 9.9 283 10.4 284 10.8 240 8.7 266 14.1 264 9.6 Source1 starter only 0 407 UAN 135 431 Nitamin 30L 135 421 397 GP-43G 135 Dicyanamide 135 421 ESN2 392 135 Lsd.05 Lsd.10 CV (%) P < 36.5 30.2 6.1 0.25 17.9 4.1 41.1 14.8 3.4 34.0 7.3 7.2 25.1 0.41 0.029 0.11 1 Materials applied at cracking and/or hilling. Gravity 1.078 1.076 1.075 1.076 1.075 1.075 .0016 .0014 0.10 0.029 84 Weed Control and Potato Crop Tolerance  Christy Sprague and Gary Powell  MSU Crop and Soil Science      Several herbicides were evaluated for preemergence (PRE) and postemercence (POST) weed  control in potato.  The variety ‘Snowden’ was planted May 9, with PRE applications May 23,  after hilling.  POST applications were made June 15, with potato at 12” height, and annual  weeds ½ to 6 inch height.    Common lambsquarters was the most difficult weed species to control.  PRE application of Dual  Magnum (trt #13) resulted in very poor control of both lambsquarters and redroot pigweed.   The addition of Reflex to the PRE application of Dual (trt #14) greatly improved lambsquarters  control and resulted in excellent pigweed control.  A PRE tank‐mix of Matrix + Dual  followed by  Matrix  POST  (trt #9) resulted in fair lambsquarters control; this same PRE tank‐mix followed by  Valent’s experimental V‐10142 POST (trt #10) resulted in excellent lambsquarters control.  A  PRE application of V‐10142 resulted in fair to good lambsquarters control (trt #1‐3), while this  same PRE application followed by V‐10142 applied POST resulted in good to excellent  lambsquarters control (trt #4,5,6,8).  Boundary (a premix of Dual + Sencor) applied PRE alone or  tank‐mixed with Reflex (trt #15,16) resulted in excellent weed control.    A PRE application of Valent’s Chateau (trt # 12) resulted in the only injury to potato.  Injury  consisted of severe potato stunting and stand reduction.            MSU Weed Science Research Program Weed Control and Potato Crop Tolerance Trial ID: POT01-07 Study Dir.: Sprague, Powell Conducted: Montcalm Investigator: Christy Sprague Date Planted: 5/9/07 Row Spacing: 34" IN Variety: Snowden No. of Reps: 4 Population: 12" Seed Spacing % OM: 2.5 Soil Type: Loamy Sand pH: 4.9 Plot Size: 10 X 30 FT Design: RANDOMIZED COMPLETE BLOCK Tillage: Moldboard Plowed and raked 5/9/07 Fertilizer: 250lb Potash Plowdown 20 gallon 19-17-0 with planter 8oz Admire with planter 85 Crop and Weed Description CHENOPODIUM ALBUM L. ECHINOCHLOA CRUS-GALLI AMARANTHUS RETROFLEXUS L. CHEAL ECHCG AMARE LAMBSQUARTERS, COMMON BARNYARDGRASS PIGWEED, REDROOT SOLTU POTATO B 6/15/07 15 80 F 36 77 F 5 5 Weed Code Common Name Scientific Name 1. 2. 3. Crop Code Common Name 1. Application Description A Application Timing: PRE POST Date Treated: 5/23/07 Time Treated: 8:15 pm 9:30 am % Cloud Cover: 10 Air Temp., Unit: 80 F % Relative Humidity: 25 Wind Speed/Unit/Dir: 2 mph W 1 mph W Soil Temp., Unit: 76 F Soil/Leaf Surface M: 5 5 Soil Moist (1=w 5=d): 5 5 Crop Stage at Each Application A Crop Name: SOLTU SOLTU Height (In.): - 10-12 Stage (L): - many Weed Stage at Each Application A Weed 1 Name: CHEAL CHEAL Height (In.): - 1/2-3" Stage (L): - coty-12 Weed 2 Name: ECHCG ECHCG Height (In.): - 2" Stage (L): - 1-2 Weed 3 Name: AMARE AMARE Height (In.): 1" Stage (L): 6 Weed Density (plants/sq. ft.) 1 4 Date: 7/16/07 7/16/07 7/16/07 7/16/07 Weed Name: ECHCG CHEAL AMARE POLCO Density: <1 2 <1 <1 Application Equipment Appl Sprayer Speed Nozzle Nozzle Nozzle Nozzle Boom A B MPH Type Size Height Spacing Width GPA Carrier PSI 100 19 water 27 3.8 AirMix 11003 22" 3.8 AirMix 11003 20" 100 19 water 27 Type Cub Cub B B 2 3 20 20 86 MSU Weed Science Research Program 92 99 L L L V-10142 78 91 92 81 94 99 97 97 V-10142 V-10142 0 0 0 0 oz/a PRE A 0 0 0 0 0 0 oz/a PRE A 75 WG 8.5 75 WG 6.4 75 WG 8.5 75 WG 8.5 75 WG 6.4 75 WG 6.4 75 WG 10.67 oz/a PRE A V-10142 V-10142 Acitvator 90 (NIS) V-10142 V-10142 Acitvator 90 (NIS) Form Form Conc Type Rate Unit Stg Rate Grow Appl V-10142 V-10142 Acitvator 90 (NIS) oz/a PRE A oz/a POST B 0.25 % v/v POST B oz/a PRE A oz/a POST B 0.25 % v/v POST B 75 WG 10.67 oz/a PRE A 75 WG 8.5 oz/a POST B 0.25 % v/v POST B Weed Control and Potato Crop Tolerance Trial ID: POT01-07 Study Dir.: Sprague, Powell Conducted: Montcalm Investigator: Christy Sprague Weed Code Crop Code Rating Data Type Rating Unit Rating Date Trt-Eval Interval Trt Treatment No. Name 1 2 3 4 4 4 5 5 5 6 6 6 7 Untreated 8 8 Dual Magnum 8 8 9 Matrix 9 Dual Magnum 9 Matrix 9 10 Dual Magnum 10 Sencor 10 V-10142 10 Acitvator 90 (NIS) 11 Dual Magnum 11 Sencor 11 Matrix 11 Acitvator 90 (NIS) 12 Chateau 13 Dual Magnum 14 Dual Magnum 14 Reflex 15 Boundary 16 Boundary 16 Reflex LSD (P=.05) Standard Deviation CV pt/a PRE A oz/a PRE A oz/a POST B 0.25 % v/v POST B pt/a PRE A oz/a PRE A oz/a POST B 0.25 % v/v POST B oz/a PRE A pt/a PRE A oz/a POST B 0.25 % v/v POST B oz/a PRE A pt/a PRE A oz/a POST B 0.25 % v/v POST B 7.62 EC 1 75 WG 4 75 WG 8.5 75 WG 6.4 7.62 EC 75 WG 8.5 1 7.62 EC 1 75 WG 4 25 WG 1 25 WG 1 7.62 EC 1 25 WG 1 V-10142 Acitvator 90 (NIS) pt/a PRE A pt/a PRE A pt/a PRE A pt/a PRE A Acitvator 90 (NIS) 6.5 EC 2 L 7.62 EC 2 L 51 WG 1.5 2.1 1.4 51.32 1.0 0.7 15.93 pt/a PRE A pt/a PRE A oz/a PRE A 0 0 0 0 0 0 0 0 4.4 3.1 3.35 6.5 EC 7.62 EC 8.4 5.9 7.5 V-10142 96 99 99 99 15 96 1.5 1.5 0.5 0 0 0 0 0 94 0 99 99 98 99 99 0 0 0 0 0 0 0 L L L L 1 1 1 35 99 92 99 98 99 98 99 73 45 0 injury CHEAL ECHCG control SOLTU SOLTU control injury percent percent percent percent percent percent percent percent 6/7/07 6/15/07 6/15/07 6/15/07 6/28/07 6/28/07 6/28/07 6/28/07 15 DA-A 23 DA-A 23 DA-A 23 DA-A 36 DA-A 36 DA-A 36 DA-A 36 DA-A Code ECHCG CHEAL AMARE control SOLTU injury control control 0 0 0 0 0 0 0 0 0 0 0 33 0 0 0 0 92 99 91 98 73 73 79 73 99 99 99 99 99 92 99 97 95 99 0 99 0 96 0 99 99 75 99 99 99 99 99 98 99 85 99 99 99 99 98 30 79 96 92 97 25 99 98 99 9.0 9.0 6.3 6.3 311.77 6.95 11.3 7.9 10.12 2.6 1.8 2.08 87 MSU Weed Science Research Program 99 99 98 95 99 91 V-10142 V-10142 V-10142 L L L 99 99 87 99 98 99 74 85 88 86 99 99 99 99 control 99 99 control oz/a PRE A oz/a PRE A 75 WG 8.5 75 WG 6.4 75 WG 8.5 75 WG 8.5 75 WG 6.4 75 WG 6.4 75 WG 10.67 oz/a PRE A V-10142 V-10142 Acitvator 90 (NIS) V-10142 V-10142 Acitvator 90 (NIS) V-10142 V-10142 Acitvator 90 (NIS) oz/a PRE A oz/a POST B 0.25 % v/v POST B oz/a PRE A oz/a POST B 0.25 % v/v POST B Form Form Conc Type Rate Unit Stg Rate Grow Appl 75 WG 10.67 oz/a PRE A 75 WG 8.5 oz/a POST B 0.25 % v/v POST B Weed Control and Potato Crop Tolerance Trial ID: POT01-07 Study Dir.: Sprague, Powell Conducted: Montcalm Investigator: Christy Sprague AMBEL ECHCG CHEAL AMARE Weed Code Crop Code control Rating Data Type control percent percent percent percent Rating Unit 6/28/07 7/26/07 7/26/07 7/26/07 Rating Date 36 DA-A 64 DA-A 64 DA-A 64 DA-A Trt-Eval Interval Trt Treatment No. Name Code 1 2 3 4 4 4 5 5 5 6 6 6 7 Untreated 8 8 Dual Magnum 8 8 9 Matrix 9 Dual Magnum 9 Matrix 9 10 Dual Magnum 10 Sencor 10 V-10142 10 Acitvator 90 (NIS) 11 Dual Magnum 11 Sencor 11 Matrix 11 Acitvator 90 (NIS) 12 Chateau 13 Dual Magnum 14 Dual Magnum 14 Reflex 15 Boundary 16 Boundary 16 Reflex LSD (P=.05) Standard Deviation CV pt/a PRE A oz/a PRE A oz/a POST B 0.25 % v/v POST B pt/a PRE A oz/a PRE A oz/a POST B 0.25 % v/v POST B oz/a PRE A pt/a PRE A oz/a POST B 0.25 % v/v POST B oz/a PRE A pt/a PRE A oz/a POST B 0.25 % v/v POST B 7.62 EC 1 75 WG 4 75 WG 8.5 75 WG 6.4 7.62 EC 75 WG 8.5 1 7.62 EC 1 75 WG 4 25 WG 1 25 WG 1 7.62 EC 1 25 WG 1 V-10142 Acitvator 90 (NIS) pt/a PRE A pt/a PRE A pt/a PRE A pt/a PRE A Acitvator 90 (NIS) 6.5 EC 2 L 7.62 EC 2 L 51 WG 1.5 12.6 8.8 10.98 pt/a PRE A pt/a PRE A oz/a PRE A 4.3 3.0 3.28 10.5 7.4 8.1 93 99 99 99 99 99 86 99 99 89 30 78 92 80 99 99 1.5 1.5 0.5 99 99 6.5 EC 7.62 EC 9.8 6.8 7.5 V-10142 L L L L 99 99 97 99 0 99 84 99 0 98 99 99 0 99 0 99 99 99 99 99 94 95 98 99 1 1 1 88 Funding: MPIC and Aghem Industry Seed, in-furrow and emergence treatments for control of seed- and soil-borne Rhizoctonia, 2007. W. W. Kirk, R. L Schafer, P. S. Wharton and P. Tumbalam. Department of Plant Pathology, Michigan State University East Lansing, MI 48824 Potatoes (FL1879) with Rhizoctonia solani (black scurf), 2- 5% tuber surface area infected, were selected for the trials. Potato seed was prepared for planting by cutting and treating with fungicidal seed treatments two days prior to planting. Seed were planted at the Michigan State University Muck Soils Experimental Station, Bath, MI on 10 Jun into two- row by 20-ft plots (ca. 10-in between plants to give a target population of 50 plants at 34-in row spacing) replicated four times in a randomized complete block design. The two-row beds were separated by a five-foot unplanted row. Dust formulations were measured and added to cut seed pieces in a Gustafson revolving drum seed treater and mixed for two minutes to ensure even spread of the fungicide. Fungicides applied as pre-planting potato seed liquid treatments were applied in water suspension at a rate of 0.2 pt/cwt onto the exposed seed tuber surfaces, with the entire seed surface being coated in the Gustafson seed treater. Foliar applications were applied with a R&D spray boom delivering 25 gal/A (80 p.s.i.) and using three XR11003VS nozzles per row. Fertilizer was drilled into plots before planting, formulated according to results of soil tests. Additional nitrogen (final N 28 lb/A) was applied to the growing crop with irrigation 45 DAP (days after planting). Previcur Flex was applied at 0.7 pt/A on a seven day interval, total of four applications, starting 1 day after inoculation of adjacent plots with Phytophthora infestans. A permanent irrigation system was established prior to the commencement of fungicide sprays and the fields were maintained at soil moisture capacity throughout the season by frequent (minimum 5 day) irrigations. Weeds were controlled by hilling and with Dual 8E at 2 pt/A 10 DAP, Basagran at 2 pt/A 20 and 40 DAP and Poast at 1.5 pt/A 58 DAP. Insects were controlled with Admire 2F at 1.25 pt/A at planting, Sevin 80S at 1.25 lb/A 31 and 55 DAP, Thiodan 3 EC at 2.33 pt/A 65 and 87 DAP and Pounce 3.2EC at 8 oz/A 48 DAP. Vines were killed with Reglone 2EC (1 pt/A on 20 Sep). Plots (20-ft row) were harvested on 29 Oct and individual treatments were weighed and graded. Four plants per plot were harvested 10-days after the final treatment application (13 Jul) and the percentage of stems and stolons with greater than 5% of the total surface area were counted. Samples of 50 tubers per plot were harvested 14 days after desiccation and assessed for black scurf (R. solani) incidence (%) and severity 40 days after harvest. Severity of black scurf was measured as an index calculated by counting the number of tubers (n = 50) falling in class 0 = 0%; 1 = 1 - 5%; 2 = 6 - 10%; 3 = 11 - 15; 4 >15% surface area of tuber covered with sclerotia. The number in each class is multiplied by the class number and summed. The sum is multiplied by a constant to express as a percentage. Indices of 0 - 25 represent 0 - 5%; 26 - 50 represent 6 - 10%; 51 - 75 represent 11 - 15% and 75 - 100 >15% surface area covered with sclerotia. Maximum, minimum and average daily air temperature (oF) were 91.3, 36.1 and 66.6 and 2-d with maximum temperature >90oF (Jun); 95.2, 37.7 and 67.0 and 4-d with maximum temperature >90oF (Jul); 93.4, 36.3 and 68.7 and 4-d with maximum temperature >90oF (Aug); 90.0, 34.1 and 63.4 and 1-d with maximum temperature >90oF (Sep). Maximum, minimum and average daily soil temperature (oF) were 75.1, 53.1 and 65.8 (May); 82.1, 53.2 and 68.2 (Jun); 83.1, 53.7 and 65.3 (Jul); 80.5, 54.5 and 67.1 (Aug); 77.1, 51.3 and 66.4 (Sep). Maximum. minimum and average soil moisture (% of field capacity) 79.0, 75.2 and 77.3 (May); 91.7, 77.2 and 81.3 (Jun); 82.1, 74.1 and 77.9 (Jul); 98.1, 75.4 and 80.7 (Aug); 76.2, 66.6 and 69.8 (Sep). Precipitation was 0.99 in. (May), 3.91 in. (Jun), 0.80 in. (Jul), 6.18 in. (Aug) and 1.09 in. (Sep). Plots were irrigated to supplement precipitation to about 0.1 in./A/4 day period with overhead sprinkle irrigation. No treatment affected final plant stand or RAUEPC and were not significantly different from the untreated control. Marketable yield ranged from 189 to 287 cwt/A (not-treated check = 195 cwt/A) and treatments with greater than 247 cwt/A were significantly different from the untreated check and Maxim FS (ST). Total yield ranged from 229 to 325 cwt/A (untreated check = 239 cwt/A) and treatment with greater than 289 cwt/A had significantly greater total yield than the untreated check and Maxim FS (ST). No treatment affected the total number of stolons or stem number per plant. Treatments with less than 8.7% incidence of stolon canker and less than 5.5% incidence of stems with greater than 5% girdling due to stem canker were significantly different from the untreated control. No treatment affected the incidence or severity of black scurf on tubers evaluated 40 days after harvest. Seed treatments and seed treatment plus fungicide applications of fungicides were not phytotoxic. 89 Funding: MPIC and Aghem Industry Table 1 Treatment and rate/1000 row feet and rate/cwt potato seedz LEM 17 200EC 0.67 fl oz (B)…. LEM 17 200EC 1.63 fl oz (B)…. LEM 17 200EC 3.26 fl oz (B)…. LEM 200SC 0.67 fl oz (B)…….. LEM 200SC 1.63 fl oz (B)…….. LEM 200SC 3.26 fl oz (B)…….. Quadris 2.08SC 0.4 fl oz (B)…… Evito 4FL 0.26 fl oz (B)………... Evito 4FL 0.26 fl oz (C)………... Maxim 4FS 0.16 fl oz/cwt (A)…. Weco 0406 4FS 0.5 fl oz/cwt (A). Weco 143 4FS 0.5 fl oz/cwt (A)... Untreated Check………………... HSD0.05 Final plant stand (%) RAUEPC 96.3 87.5 86.3 82.5 85.6 88.8 87.5 87.5 85.0 72.5 84.4 88.1 85.6 12.81 31.3 35.9 35.5 29.8 37.6 30.9 32.8 31.1 31.2 24.5 32.4 35.1 35.3 8.03 Yield (cwt/A) US1 235 b-e 275 abc a-d 249 ab 279 272 a-d 228 def a 287 230 c-f 228 def 189 247 277 195 f a-d ab ef Total 268 b-e 314 ab abc 289 a 318 a 317 265 cde a 325 267 cde 268 b-e e 229 a-d 282 317 a 239 de 45.5 46.2 Number Percent infected Number/ Incidence (%) Severity scale (0 - 100) Stolons (55 DAP) Stems (55 DAP) Tuber black scurf Treatment and rate/1000 row feet and rate/cwt potato seed LEM 17 200EC 0.67 fl oz (B)…. LEM 17 200EC 1.63 fl oz (B)…. LEM 17 200EC 3.26 fl oz (B)…. LEM 200SC 0.67 fl oz (B)…….. LEM 200SC 1.63 fl oz (B)…….. LEM 200SC 3.26 fl oz (B)…….. Quadris 2.08SC 0.4 fl oz (B)…… Evito 4FL 0.26 fl oz (B)………... Evito 4FL 0.26 fl oz (C)………... Maxim 4FS 0.16 fl oz/cwt (A)…. Weco 0406 4FS 0.5 fl oz/cwt (A). Weco 143 4FS 0.5 fl oz/cwt (A)... Untreated Check………………... HSD0.05 z Stems with greater than 5% of area with stem canker due to Rhizoctonia solani. y Stolons with greater than 5% of area with stolon canker due to Rhizoctonia solani. x Application dates: A= 13 Jun (liquid formulations for seed piece application at 0.2 pt/cwt; B= 13 Jun (in-furrow); C= 29 Jun (banded over row). w Values followed by the same letter are not significantly different at p = 0.05 (Tukey Multiple Comparison). Girdling > 5% 17.4 13.2 8.9 12.9 14.2 5.5 18.4 16.6 33.4 3.7 6.4 7.1 22.0 2.93 22.7 15.1 10.0 14.0 16.7 8.7 21.2 32.9 43.3 6.7 11.7 17.5 26.0 14.82 23.5 21.2 25.3 23.0 21.0 24.4 23.4 20.4 20.8 23.7 25.6 21.8 22.4 4.30 37.5 39.7 38.8 37.8 42.5 35.6 44.7 35.9 49.7 33.1 42.8 41.9 50.6 25.47 96.3 88.8 90.0 91.3 100.0 92.5 100.0 83.8 100.0 81.3 100.0 95.0 97.5 32.69 plant 3.5 3.6 3.3 3.3 3 4 3.4 3.2 3.1 3.6 3.9 3.4 3.3 1.10 bcd cde de cde cde de b-e ab a e cde cde bc bcd c-f def c-f c-f ef b-e ab a f c-f b-f abc 90 In-furrow at planting and foliar treatments for control of common scab in potato, 2007 W. W. Kirk, J. Hao, and R. Schafer (PLP). Michigan State University, East Lansing, MI 48824 Funding; MSU GREEEN and MPIC Potato seed, ‘Goldrush’ was prepared for planting by cutting seven days prior to planting. Seed were planted at the Michigan State University Muck Soils Farm, East Lansing, MI, mineral soil block, on 13 Jun into four-row by 12-ft plots with 10-in between plants at 34-in row spacing replicated eight times in a randomized complete block design. The four-row beds were separated by a five-foot unplanted row. Fertilizer was drilled into plots before planting, formulated according to results of soil tests. Additional nitrogen (final N 28 lb/A) was applied to the growing crop with irrigation 45 DAP (days after planting). Potatoes had been grown at this site for 3 of 5 previous years at this site, which had a history of moderate common scab. Additional inoculum was added to the site by spraying a water solution (20 gal/A) containing 2 x 103 spores/fl oz of Streptomyces scabies over the whole field at plant emergence. In-furrow applications were made at planting, applied with a single nozzle R&D spray boom delivering 8 gal/A (80 p.s.i.) and using one XR11003VS nozzle per row. Bravo WS 6SC was applied at 1.5 pt/A on a 7-day interval, total of 8 applications, starting after the canopy was about 50% closed. Minimal supplemental irrigation was applied to the trial, and soil moisture was maintained at about 60-70% field capacity. Weeds were controlled by hilling and with Dual 8E at 2 pt/A 10 DAP, Basagran at 2 pt/A 20 and 40 DAP and Poast at 1.5 pt/A 58 DAP. Insects were controlled with Admire 2F at 1.25 pt/A at planting, Sevin 80S at 1.25 lb/A 31 and 55 DAP, Thiodan 3 EC at 2.33 pt/A 65 and 87 DAP and Pounce 3.2EC at 8 oz/A 48 DAP. Vines were killed with Reglone 2EC (1 pt/A on 3 Oct). Plots (24-ft row, center 2-rows) were harvested on 17 Oct and individual treatments were weighed and graded. Samples of 100 tubers per plot were stored at 50oF and evaluated 14 days after desiccation (126 DAP). Tubers were washed and assessed for common scab (S. scabies) incidence (%) and severity. Severity of common scab was measured as an index calculated by counting the number of tubers (n = 100) falling in class 0 = 0%; 1 = 1 - 5%; 2 = 6 -10%; 3 = 11 - 15; 4 >16% surface area of tuber covered with tuber lesions (surface and pitted). The number in each class was multiplied by the class number and summed. The sum was multiplied by a constant to express as a percentage. Indices of 0 - 25 represent 0 - 5%; 26 - 50 represent 6 - 10%; 51 - 75 represent 11 - 15% and 75 - 100 >15% surface area covered with lesions. Very little common scab developed on tubers in this trial in part due to the relative resistance of cv. Goldrush to S. scabies. There were no differences among treatments in terms of incidence or severity of common scab. Messenger applied two weeks after canopy closure (C) and 14 days later (D) significantly increased marketable (US-1) yield in comparison with the non-treated control, Blocker applied in-furrow at planting and the triple-applications of Messenger. There appears to be a complex response in cv. Goldrush to timing of applications of Messenger. No phytotoxicity was observed in this trial. Table 1. Efficacy of in-furrow at-planting fungicide application of Blocker and of Messenger applied to foliage on incidence and severity of common scab and yield in cv. Goldrush. Common scab Yield (cwt/A) Percentage in Scab severity US-1 grade bx 241 244 b indexy 11.5 9 Class 0z 62.5 70.4 Treatment rate/A or rate/1000 ft row Untreated Blocker 38.3F 2.6 pt/1000 ft row (Aw) Blocker 38.3F 2.6 pt/1000 ft row (A) Messenger 3WDG 3 oz (B,C,D) Messenger 3WDG 3 oz (B,C,D) Messenger 3WDG 3 oz (C,D) LSDp=0.05v z Scab-free tubers. y Severity of common scab was measured as an index calculated by counting the number of tubers (n = 200) falling in class 0 = 0%; 1 = 1 - 5%; 2 = 6 -10%; 3 = 11 - 15; 4 >16% surface area of tuber covered with tuber lesions (surface and pitted). x Values followed by the same letter are not significantly different at P = 0.05 (Fishers protected LSD). w Application dates: A= 13 Jun; B= 11 Jul; C= 25 Jul; D= 8 Aug. v LSDp=0.05 included if no significant difference among mean values. 291 ab 237 b 327 a 68.0 7.9 11.9 10.3 3.71 72.9 64.6 67.9 10.32 65 56 68 20.9 b-grade 56 53 91 Host Plant Resistance and Reduced Rates and Frequencies of Fungicide Application to Control Potato Late Blight (2007). W.W. Kirk1, P. Tumbalam, R. Schafer, D.S. Douches2. 1Plant Pathology, 2Crop and Soil Sciences, Michigan State University Funding: MPIC and MSU Late blight of potato caused by Phytophthora infestans (Mont de Bary), is a major threat to the production of high quality potatoes. Unchecked, P. infestans can rapidly defoliate plants in the field and can infect potato tubers when spores are washed into the soil. Potato late blight control strategies changed following the migration of mefenoxam/metalaxyl-resistant populations of P. infestans from Mexico to North America and necessitate cultural control methods and crop protection strategies that rely primarily on protectant foliar fungicide applications. There are several potential methods for reducing fungicide inputs in potato crop management. These include the use of fungicides with less active ingredient, reduced application rates, longer application intervals and a combination of any of these strategies. There are currently few late blight resistant potato cultivars that meet commercial standards in the United States. Typical fungicide application programs use a 5- 7 day spray interval depending on environmental conditions and grower preference. The frequent fungicide spray intervals and rates currently used by growers to control late blight are expensive and more economical control measures are needed. Therefore, the objective of this research was to determine if acceptable control of foliar late blight can be achieved by using increased fungicide spray intervals and reduced application rates of residual contact fungicides on potato germplasm with a range of susceptibility to late blight developed at the potato breeding program at Michigan State University. Previous experiments from the MSU breeding program identified potato cultivars and advanced breeding lines (ABL) with different responses to foliar late blight. All experiments were conducted at the Michigan State University Muck Soils Research Station, Bath, MI (90% organic muck soil). Soils were plowed to 9” cm depth during Oct following harvest of preceding crops. Soils were prepared for planting with a mechanical cultivator in early May and fertilizer applied during final bed preparation on the day of planting. Cultivars/ABL were planted on 4 Jun, 2005 in two-row by 50 ft plots (34” row spacing). The experimental design for the fungicide application interval and reduced dose rate trials was a randomized complete block design with four replications. Fertilizers were applied in accordance with results from soil testing carried out in the spring of each year and about 200 cwt N/A (total N) was applied in two equal doses at planting and hilling. Additional micronutrients were applied according to petiole sampling recommendations and in all years. Approximately 0.2, 0.3 and 0.2 cwt/A boron, manganese and magnesium, respectively were applied as chelated formulations. Cut and whole seed pieces (2.5 -5.0 oz) of selected cultivars and ABL were used in all experiments. When relative humidity (RH) dipped below 80% (measured with RH sensors mounted within the canopy, described below), a mist irrigation system (described below) was turned on to maintain RH at >95% within the plant canopy. Plots were irrigated as necessary to maintain canopy and soil moisture conditions conducive for development of foliar late blight with turbine rotary garden sprinklers (Gilmour Group, Somerset, PA, U.S.A.) at 112 gal H2O A/hr and managed under standard potato agronomic practices. Weeds were controlled by hilling and with Dual 8E (2 pt/A on 28 Jun), Basagran (2 pt/A on 28 Jun and 25 Jul) and Poast (1.5 pt/A on 25 Jul). Insects were controlled with Admire 2F (20 fl oz/A at planting on 28 Jun), Sevin 80S (1.25 lb/A on 11 and 25 Jul), Thiodan 3EC (2.33 pt/A on 1 and 21 Aug) and Pounce 3.2EC (8 oz/A on 25 Jul). MATERIALS AND METHODS Potato Germplasm, agronomy and experimental design 92 Residual Contact Fungicides Funding: MPIC and MSU Bravos WS 6SC (Syngenta) was used for this experiment. Fungicides were applied with an ATV rear-mounted spray boom (R&D Sprayers, Opelousas, LA) 20 gal H2O/A (80 psi pressure) with three XR11003VS nozzles per row positioned 12” apart and 18” above the canopy. In the fungicide application interval and reduced dose rates trial, Bravo WS was applied at 7 and 14 day intervals at 0, 50 and 100% MRAR to the ABL and cultivars described in Table 1. The first fungicide application occurred at 32 days after planting (DAP; 5 Jul, 2005) when potato plants were approximately 6” tall. Fungicides were applied until non-treated plots of susceptible controls reached about 100% diseased foliar area (4 Sep). The 7, and 14-day interval treatments received eight and four applications in 2007, respectively. Pathogen Preparation and Inoculation. Zoospore suspensions were made from P. infestans cultures of several isolates from different genetic backgrounds, including (US8 and US14 genotypes, insensitive to mefenoxam/metalaxyl, A2 mating types) grown on rye agar plates for 14 days in the dark at 15oC. Sporangia were harvested from the rye agar plates by rinsing the mycelial/sporangial mat in cold (4oC) sterile, distilled water and scraping the mycelial/sporangial mat from the agar surface with a rubber policeman. The mycelial/sporangial suspension was stirred with a magnetic stirrer for 1 hour. The suspension was strained through four layers of cheesecloth and the concentration of sporangia was adjusted to about 1 x 102 sporangia/fl oz using a hemacytometer. Sporangial cultures were incubated for 2-3 hours at 40oF to stimulate zoospore release. All plots were inoculated simultaneously through an overhead sprinkler irrigation system, on 27 Jul, 2005; by injecting the zoospore suspension of P. infestans into the irrigation water feed pipeline at 20 psi CO2 pressure and applied at a rate of about at 104 spores/fl oz over the whole trial area. The amount and rate of inoculum applied was estimated from prior calibration of the irrigation system (described above) and was intended to expose all potato foliage to inoculum of P. infestans. Disease Evaluation and Data Analysis As soon as late blight symptoms were detected (about 10 days after inoculation, DAI), each plant within each plot was visually rated at 3 to 5 day intervals for percent leaf and stem (foliar) area with late blight lesions on 30 Jul; 11, 17, 24 Aug and 2 and 13 Sep [13 days after final application (DAFA), 41 DAI in 2007] when there was about 100% foliar infection in the untreated plots. The mean percent blighted foliar area per treatment was calculated. In the present study, any cultivar/ABL with foliar late blight severity measured as the Relative Area Under the Disease Progress Curve [RAUDPC]. Fungicide treatments were classified into three groups; non-effective if the RAUDPC was not significantly different from the non-treated control value for the susceptible variety (NE); partially effective if significantly less than the non-treated control for the susceptible variety and significantly greater than the 100% MRAR, 7-day frequency application for the resistant variety (PE); and effective if the RAUDPC was not significantly different from 100% MRAR, 5-day frequency application for the resistant variety (E). Microclimate Measurement Climatic variables were measured with a Campbell Weather Station equipped with air temperature and humidity sensors located within the potato canopy on site. Microclimate within the potato canopy was monitored beginning when 50% of the potato plants had emerged and ending when canopies of healthy plants reached 100% senescence. The Wallin Late Blight Prediction Model was developed in the Eastern United States under conditions similar to those in Michigan and was adapted to local conditions. Late blight disease severity values (DSV) were estimated from the Wallin Late Blight Prediction Model and accumulated from inoculation to final evaluation to estimate 93 the conduciveness of the environment for late blight development. Funding: MPIC and MSU RESULTS Microclimate conditions Late blight developed slowly during August due to high temperatures; non-treated susceptible controls reached about 100% diseased foliar area 42 DAI. Meteorological variables were measured with a Campbell weather station located at the farm, latitude 42.8269 and longitude - 84.365deg. Maximum, minimum and average daily air temperature (oF) were 88.0, 39.6 and 64.9 and 0-d with maximum temperature >90oF (May); 91.3, 36.1 and 66.6 and 2-d with maximum temperature >90oF (Jun); 95.2, 37.7 and 67.0 and 4-d with maximum temperature >90oF (Jul); 93.4, 36.3 and 68.7 and 4-d with maximum temperature >90oF (Aug); 90.0, 34.1 and 63.4 and 1-d with maximum temperature >90oF (Sep). Maximum, minimum and average daily soil temperature (oF) were 75.1, 53.1 and 65.8 (May); 82.1, 53.2 and 68.2 (Jun); 83.1, 53.7 and 65.3 (Jul); 80.5, 54.5 and 67.1 (Aug); 77.1, 51.3 and 66.4 (Sep). Maximum, minimum and average soil moisture (% of field capacity) were 79.0, 75.2 and 77.3 (May); 91.7, 77.2 and 81.3 (Jun); 82.1, 74.1 and 77.9 (Jul); 98.1, 75.4 and 80.7 (Aug); 76.2, 66.6 and 69.8 (Sep). Precipitation was 0.99 in. (May), 3.91 in. (Jun), 0.80 in. (Jul), 6.18 in. (Aug) and 1.09 in. (Sep). The total number of late blight disease severity values (DSV) over the disease development period was 62 using 90% ambient %RH as a base for DSV accumulation. This indicated that environmental conditions were conducive to late blight development (DSV > 18). Foliar late blight developed steadily from inoculation to 35 days after inoculation when the most susceptible variety (Snowden) was completely defoliated in one replicate. The late blight responses of the different cvs/ABLs are shown in Table 1. The RAUDPC of the susceptible cultivars ranged from 13.6 to 19.9 mean RAUDPC and included MSE69.06, MSE69.03, MSI211-3 and Snowden (19.9). The transgenic variety RB Spunta was intermediate between susceptible and resistant groups with an RAUDPC of 5.3 in the untreated control. No late blight developed on any other MSJ461-1 and Stirling and they were classified as resistant (Table 1). Application of Bravo WS at full rate of application at 7 or 14-day intervals resulted in effective control of late blight in all varieties except MSI211-3 (Table 1). Application of Bravo WS at 50% rate of application at 7 or 14-day intervals resulted in effective control of late blight in MSE69.03, Snowden, and MSE69.06. In MSI211-3, application of Bravo WS resulted in non-effective control of potato late blight. In RB Spunta, the application of fungicides at any rate or frequency numerically reduced the RAUDPC but not significantly in comparing to the non-treated control. The RAUDPC and the final late blight severity scores for the non-treated RB Spunta plots were not significantly different from those of the MSJ461-1 or Stirling responses (which were = 0 for all rates and application frequencies). DISCUSSION The results of this study were consistent with previous studies and indicate that a combination of cultivar/ABL resistance and managed application of protective fungicides will reduce foliar late blight to acceptable levels in most situations. When conditions were less conducive to late blight development (as in 2007), reduced amounts of Bravo WS were either fully or partially effective at most application rates tested on all cultivars/ABL compared to the non-treated controls. However, in some cultivars/ABL, 50% of the MRAR of fungicide was sufficient to achieve acceptable control, whereas other cultivars/ABL required 100% MRAR to control late blight. On late blight susceptible cultivars, applications of Bravo WS at either 7 or 14-day intervals were at least partially effective for controlling late blight at the doses tested. However, in the resistant cultivars the fungicides did not reduce the RAUDPC in comparison with untreated plots of these cultivars and fungicides are not required for late blight control in these entries. The opportunity to manage late blight by applying reduced rates of fungicides at increased 94 Funding: MPIC and MSU spray intervals to cultivars less susceptible to late blight was demonstrated in this study. In addition, the efficacy of reduced rates and increased application intervals of fungicides against other potato pathogens such as early blight has not been established and may prove to be a major constraint in the adoption of managed fungicide applications. As new cultivars with enhanced late blight resistance are developed and released it will be important to provide growers with recommendations for the most effective and economical chemical control of late blight in these new cultivars. In the future, the type of information gathered in this study will be used to develop models, based on cultivar resistance and response to fungicide application, to advise and guide growers as to which fungicide, rate and frequency of application is required to provide protection against late blight. Climatic conditions within the canopy will also impact choice of fungicide and rate and frequency of application. Therefore, new cultivars will need to be carefully screened in the manner described in this study, over several seasons in order to develop accurate models for fungicide application. ACKNOWLEDGMENTS This research was funded in part by the Michigan Agricultural Experiment Station and Michigan Potato Industry Commission. Mention of a brand or trade name does not constitute an endorsement. 95 Table 1. Funding: MPIC and MSU Foliar late blight (%) Application frequency (days) 0.75 0.75 f f f f f 0.75 1.5 0 0.75 5.8 bcd 0 0 0 0 0 1.5 0 1.5 0 1.5 0 Fungicide rate (pt/a) 0 e 0 e 0 e 0 e 0 e 0 d 0 d 0 d 0 d 0 d 7 14 7 14 0 7 14 7 14 0 7 14 7 14 0 7 14 7 14 0 7 14 7 14 0 7 14 7 14 0 7 14 7 14 0 22 DAI 0.5 d 1 cd 0 d 0 d 27.5 abc 43.8 a 6.5 cde 15.5 b-e 23.8 a-d 11 a-d 20 a 1.8 bcd 4 bcd 13.3 abc 35 DAI 7.5 f 27.5 c-f f 2.5 2.3 f 71.3 ab 29 DAI 2.3 de 5.8 cde 0.5 de 0.5 e 32.5 ab 58.8 abc 88.8 a 18.8 ef 51.3 bcd 83.8 a f f f f f 0 0 0 0 0 15 DAI 0 b 0 b 0 b 0 b 1 b 0 b 0 b 0 b 0 b 0 b 0.3 b 4.3 a 0 b 0.5 b 1.3 ab Cultivar/ ABL E69.03 Stirling MSI211-3 MSJ461-1 Snowden E69.06 RB Spunta 1 Varieties and advanced breeding lines from the Quad State potato breeding programs. 2 Relative area under the disease progress curve from inoculation to 100% late blight (max = 100). 3 Susceptibility of non-treated control to late blight; R = Resistant, not significantly different from Torridon (non-treated); S = Susceptible, not significantly different from Snowden (non-treated); I = Intermediate, significantly different from both Torridon and Snowden (non-treated). 4 Means followed by the same letter were not significantly different at p = 0.05. 0 b 0 b 0 b 0 b 0 b 0 b 0.3 b 0 b 0 b 4.3 a 0 b 0 b 0 b 0 b 2.3 ab 1.5 bcd 2.5 bcd 1.3 cd 1.8 bcd 20 a 0.8 d 0 d 0.3 d 0.5 d 13.8 ab 2 bcd 1.8 bcd 0.5 d 1 cd 3.5 bcd 12.44 f 16.8 f 13.8 f 0.8 8.8 f 76.3 ab 6.8 cde 15.8 b-e 0.5 de 7.5 cde 45 a 6.6 cde 1.5 de 0.3 e 2 de 32.5 ab 7 cde 7.5 cde 2.1 de 3.3 de 11.3 b-e 23.29 20 def 21.3 def 6.5 10.8 27.5 c-f 31.49 f f 0.3 b 0 b 0 b 0.3 b 0.5 b 3.15 20 def 48.8 b-e 1.3 28.8 c-f 80 ab f 0 d 0 d 0 d 0 d 0 d 0 e 0 e 0 e 0 e 0 e 1.5 0 1.5 0 1.5 0 0.75 0.75 0.75 RAUDPC (Max = 100) 0 – 35 DAI 1.2 e 3.7 de 0.3 e 0.3 e 13.6 abc 0 e 0 e 0 e 0 e 0 e 12.1 a-d 20.5 a 3.2 e 8.3 b-e 14.5 ab 0 e 0 e 0 e 0 e 0 e 3.3 de 7.8 b-e 0.4 e 4.3 de 19.9 a 2.8 e 1.5 e 0.2 e 1.2 e 15.7 ab 3.5 de 3.6 de 1 e 1.8 e 5.3 cde 8.95 96 Evaluation of fungicide programs for potato early blight and brown leaf spot control, 2007. W. W. Kirk, R. L Schafer, P. Tumbalam and P. Wharton. Department of Plant Pathology, Michigan State University, East Lansing, MI 48824 Funding: MPIC and Industry Potatoes (Russet Norkotah, cut seed, treated with Maxim FS at 0.16 fl oz/cwt) were planted at the Michigan State University Muck Soils Experimental Station, Bath, MI on 25 May into two-row by 25-ft plots (34-in row spacing), separated by a five-foot unplanted row and replicated four times in a randomized complete block design. Plots were irrigated as needed with sprinklers and were hilled immediately before sprays began. All fungicides in this trial were applied on a 7-day interval from 5 Jul to 29 Aug (9 applications) with an ATV rear-mounted R&D spray boom calibrated to deliver 25 gal/A (80 p.s.i.) using three XR11003VS nozzles per row. Weeds were controlled by hilling and with Dual 8E (2 pt/A on 25 May), Basagran (2 pt/A on 28 Jun and 11 Jul) and Poast (1.5 pt/A on 11 Jul). Insects were controlled with Admire 2F (20 fl oz/A at planting and on 28 Jun), Sevin 80S (1.25 lb/A on 11 and 25 Jul), Thiodan 3EC (2.33 pt/A on 1 and 21 Aug) and Pounce 3.2EC (8 oz/A on 11 Jul). Plots were rated visually for percentage foliar area affected by early blight and brown leaf spot on 15, 22, 29 Aug and 5 Sep [7 days after final application (DAFA)]. The relative area under the disease progress curve was calculated for each treatment from 5 Aug to 5 Sep, a period of 31 days. Vines were killed with Reglone 2EC (1 pt/A on 6 Sep). Plots (2 x 25-ft row) were harvested on 17 Sep and individual treatments were weighed and graded. Meteorological variables were measured with a Campbell weather station located at the farm, latitude 42.8269 and longitude -84.365deg. Maximum, minimum and average daily air temperature (oF) were 88.0, 39.6 and 64.9 and 0-d with maximum temperature >90oF (May); 91.3, 36.1 and 66.6 and 2-d with maximum temperature >90oF (Jun); 95.2, 37.7 and 67.0 and 4-d with maximum temperature >90oF (Jul); 93.4, 36.3 and 68.7 and 4-d with maximum temperature >90oF (Aug); 90.0, 34.1 and 63.4 and 1-d with maximum temperature >90oF (Sep). Maximum, minimum and average daily soil temperature (oF) were 75.1, 53.1 and 65.8 (May); 82.1, 53.2 and 68.2 (Jun); 83.1, 53.7 and 65.3 (Jul); 80.5, 54.5 and 67.1 (Aug); 77.1, 51.3 and 66.4 (Sep). Maximum, minimum and average soil moisture (% of field capacity) were 79.0, 75.2 and 77.3 (May); 91.7, 77.2 and 81.3 (Jun); 82.1, 74.1 and 77.9 (Jul); 98.1, 75.4 and 80.7 (Aug); 76.2, 66.6 and 69.8 (Sep). Precipitation was 0.99 in. (May), 3.91 in. (Jun), 0.80 in. (Jul), 6.18 in. (Aug) and 1.09 in. (Sep). The total number of late blight disease severity values (DSV) over the disease development period was 62 using 90% ambient %RH as a base for DSV accumulation. Plots were irrigated to supplement precipitation to about 0.1 in./A/4 day period with overhead sprinkle irrigation. Early blight and brown leaf spot (Alternaria complex) developed steadily in about equal proportions and untreated controls reached about 65% foliar infection by 5 Sep. Up to 5 Aug, fungicide programs with 0% Alternaria complex were significantly different from the untreated control. Alternaria developed to 8% by 22 Aug in the untreated control and programs with less than 1.5% Alternaria complex were significantly different to the untreated control but not from any other treatment. Alternaria developed to 20.0% in the untreated control by 29 Aug. Programs with 2.0 to 12.5%, 2.5 to 13.3% and 11.3 to 20.0% Alternaria complex were not significantly different. Alternaria developed to 63.8% in the untreated control by 5 Sep. All treatments had significantly less Alternaria complex in comparison to the untreated control. Programs with 7.3 to 27.5% and 11.3 to 32.5% Alternaria complex were not significantly different. All fungicide programs significantly reduced the average amount of Alternaria complex over the season (RAUDPC, 0 to 31 days after the first evaluation) compared to the untreated control. Application programs with RAUDPC values from 1.2 to 5.7 and 1.4 to 6.7 were not significantly different. There were no significant differences in marketable or total yield among treatments. Alternaria tuber blight was not observed after harvest. Phytotoxicity was not noted in any of the treatments. The Penncozeb plus Super Tin program was not within label guidelines and was included to determine if the addition of Penncozeb could ameliorate potential phytotoxic effects associated with Super Tin 80WDG. 97 Foliar early blight and brown leaf spot (%) 5 Sep 5 Aug 22 Aug 29 Aug 7 DAFAz RAUDPC Max = 100y 0 - 40 DAI Yield (cwt/A) US1 240 abc 0.0 b 0.3 b 2.8 b 0.5 ab 0.3 ab 8.8 cd 1.4 b 268 a 0.0 bw 0.8 ab 12.5 ab 31.3 bc 4.3 b 12.5 bcd 2.2 b Treatment and rate/A Sonata 500SC 4.0 pt + Dithane RS 75DF 1.5 lb + Biotune 1EC 4.5 fl oz (A,C,Ex); Headline 2.08EC 6 fl oz (B,D,F)……………………….. Headline 2.08EC 9.0 fl oz (A,E,H); Bravo ZN 6SC 1.5 pt (B,D,F,I); Endura 70WDG 2.5 oz (C,G)………………………...… Penncozeb 75DF 2.0 lb (A,B,C,D,E); Penncozeb 75DF 2.0 lb + Super Tin 80WP 5 oz (F,G,H,I)………………………… BravoWS 6SC 1.5 pt (A,C,E,F,G,H,I) Evito 4FL 3.8 fl oz + 0.125% NIS (B,D)……..……...… BravoWS 6SC 1.5 pt (A,C,E,F,G,H,I) Evito 4FL 1.9 fl oz + 0.125% NIS (B,D)……..………... Polyoxin D 2.5 WP 2.0 lb (A-I)…………….….………. LEM 17 200EC 9.6 fl oz (A-I)…………………………. LEM 17 200EC 16.8 fl oz (A-I)……………….……….. LEM 17 200EC 24.0 fl oz (A-I)……………………..…. LEM 17 200SC 16.8 fl oz (A-I)………...…….……..…. LEM 17 200SC 24.0 fl oz (A-I)……….………….....…. Tanos 50 WDG 6.0 oz + Manzate 75DF 1.5 lb (A,C,E); Manzate 75DF 1.5 lb (G); Endura 2.5 oz (B,D,F,H)…… Untreated.......................................................................... HSD0.05 z Days after final application of fungicide. y RAUDPC, relative area under the disease progress curve calculated from day of inoculation to last evaluation of late blight. x Application dates: A= 5 Jul; B= 12 Jul; B= 19 Aug; D= 25 Aug; E= 1 Aug; F= 8 Aug; G= 15 Aug; H= 22 Aug; I = 29 Aug. w Values followed by the same letter are not significantly different at p = 0.05 (Tukey Multiple Comparison). 22.5 bcd 32.5 b 27.5 bcd 12.5 bcd 20.0 bcd 11.3 bcd 7.3 d 247 abc 236 abc 209 abc 230 abc 238 abc 210 abc 212 abc 5.8 b 13.3 ab 11.3 ab 5.0 b 6.8 b 2.5 b 2.0 0.0 b 0.5 ab 0.5 ab 0.3 ab 0.3 ab 0.3 ab 0.0 b 3.7 b 6.7 ab 5.7 b 2.4 c 3.9 b 1.8 b 1.2 b 4.8 ab 1.8 ab 2.0 ab 4.0 ab 3.8 ab 0.5 b 2.8 ab 0.5 b 0.5 b 258 ab 192 c 53.7 8.8 cd 63.8 a 23.27 1.6 b 12.1 a 5.81 0.0 b 1.5 a 1.34 0.5 b 8.0 a 7.33 3.3 b 20.0 a 11.21 254 abc 223 abc 5.8 b 20.0 bcd 6.5 ab 3.5 b Total 361 a 384 a 384 a 333 a 375 a 367 a 334 a 344 a 358 a 349 a 329 a 364 a 327 a 74.8 98 Funding: MPIC and MSU GREEEN Effect of different genotypes of Phytophthora infestans and temperature on tuber disease development. William Kirk1, Dave Douches2, Pavani Tumbalam1, Rob Schafer1, Joe Coombs2 and Devan Berry2. MSU; 1Plant Pathology and 2Crop and Soil Science. Potato late blight (Phytophthora infestans Mont. de Bary) is a significant global constraint to potato production and due to conducive climatic conditions and growing practices the mid western states of the US are particularly vulnerable. The emergence and spread of new genotypes of P. infestans in North America have resulted in significant economic loss to the potato industry. The mid-west states produce about 10 million tons of potato from 150,000 planted hectares, which represents about 40% of total US production. Potato late blight affects the health of foliage and tubers limiting profitable potato production. Significant financial costs in terms of crop protection (up to $700/ha) and crop losses (up to $5,000/ha) are incurred when intervention measures to control potato late blight are unsuccessful. The newer genotypes have rapidly displaced the US-1 clonal lineage which previously had global occurrence (1, 2). In Michigan for example, the occurrence of diverse P. infestans genotypes (US-8, US-10, US-11 and US-14) has been documented in recent years (3). Rapid changes in the genetic diversity of the population of P. infestans are not predictable, but the sudden appearance and resultant predominance of the US-8 genotype, must pre-empt efforts in potato pathology and breeding to prepare for further genetic disturbance. Knowledge of competitive interactions among pathogen genotypes, fitness components and the role of resistant cultivars will enable us to develop a better understanding of the factors which govern strain selection and stability. The factors which affect frequency of occurrence of P. infestans genotypes and strain composition have not been adequately addressed. However, fungicide resistance clearly played an important role in genotype selection when phenylamide-resistant genotypes appeared globally in the 1990’s (2). Other fitness components such as temperature tolerance have not been well evaluated but their importance has recently gained credibility (5). In previous field and growth chamber studies, late blight experiments were often inoculated with single or sequential pathogen genotypes, or epidemic development was monitored under field conditions prior to determination of fungal genotype composition. Therefore, this did not address the various host – pathogen genotype interactions. Furthermore, previous studies have not taken into account the susceptibility of potato tubers to different P. infestans genotypes. This is important as late blight is readily transmitted by seed-borne inoculum (6) and consequently, immature stems and leaves may be exposed to late blight from infected seed pieces. Recent work has indicated that the new immigrant clones, especially US-8, are more aggressive in tubers and sprouts. Research at MSU has shown that most of the commonly grown potato cultivars with foliar resistance to late blight are susceptible to tuber late blight. However, several advanced breeding lines (ABL) in the MSU potato breeding program have recently been identified with tuber late blight resistance. In 2005, we evaluated 104 ABL in replicated trials and 801 early generation lines in single observation plots which resulted in 41 and 98 lines, respectively being classified as having little to no late blight infection. The value of this advanced germplasm pool is that the resistance sources are diverse suggesting that we can now combine resistance sources. 99 Funding: MPIC and MSU GREEEN The US-8 genotype of P. infestans displaced the US-1 genotype within five years of its appearance in North America, and it is vital that the industry is prepared for the supplanting of the US-8 genotype by other equally aggressive and stable genotypes of the pathogen. The proposed project, using field and controlled environment studies on potato foliage and tubers, will document whether the competitive ability of diverse P. infestans genotypes, potato cultivars/ABL with variable levels of host resistance, or environmental factors are important criteria for P. infestans genotype composition, maintenance and stability. The overall objective of this project is to develop an understanding of the factors (e.g., pathogen temperature tolerance, fitness, and host resistance) which govern pathogen genotype selection and stability. Specific objectives are to: 1. Evaluate the fitness of a variety of P. infestans genotypes on tubers of ABL (identified in objective 1) at different commonly used storage temperatures (3, 7 and 10°C). The portion of the project devoted to tuber response was initiated in 2006 and the results from the first round of experiments carried out in 2005/06 are shown in Tables 1 and 2 of the report in MIPC research report 2006/07. The main effects indicated that some varieties were more resistant to P. infestans regardless of genotype or storage temperature. The varieties MSL 183-AY, Torridon, Jacqueline-Lee and MSM 171-A were the most resistant followed by other MSU bred lines MSI 211-3. MSN 10-1, MSM 051-3 and MSJ461-1 were the most susceptible lines. The most aggressive genotype of P. infestans was US-8, followed by US-14 and US-10 then US-6. US-1 and US-11 genotypes were not particularly aggressive on the lines tested. Most tuber blight (measured as %RARI) developed at 10C followed by 7 and 3C. These results indicate that the lines MSL 183-AY, Torridon, Jacqueline-Lee and MSM 171-A could contribute to tuber blight resistance breeding efforts in the future. All three lines are partially resistant to US-8 genotype of P. infestans which is predominant in MI. The genotype was isolated from all three loci where epidemics established in MI in 2006. The results were presented as the mean tuber disease response as affected by the components of variety and storage temperature (Table 2). All varieties were partially resistant to the US-1 genotype regardless of storage temperature although some disease developed in certain varieties. Values close to zero (including negative values) indicate no establishment of P. infestans within the tubers. In some varieties late blight developed to some extent at 3C but not at higher temperatures. This is unusual but it is known that many isolates of P. infestans can survive well at temperatures close to 0C. These results indicate that P. infestans can survive well at temperatures close to 3C, the seed tuber storage temperature, which presents a risk for commercial growers even with resistant cultivars. Although varieties with partial resistance to foliar and tuber phases of potato late blight are important in the overall management of the disease these results indicate that varietal resistance is not the only component of disease management, For this reason we are proposing that varieties (close to commercial release) with partial resistance to the US-8 genotype of P. infestans are further profiled in a variety x fungicide interaction this coming year. 100 Funding: MPIC and MSU GREEEN Table 1. Main effects analyses of variety, genotype of Phytophthora infestans and temperature on tuber tissue darkening [Mean RARI (% )] in potato tubers. Genotype of P. Mean RARI ab a a b c d d d Mean RARI ( % )a 16.6 16.0 15.6 13.9 5.9 3.3 3.1 2.6 US-8 US-10 US-14 US-6 US-11 US-1 infestans Mean RARI ( % )a Variety MSN105-1 MSM051-3 MSJ461-1 MSL 211-3 MSL 183-AY Torridon Jacqueline-Lee MSM171-A a Normalized tuber tissue darkening score expressed % RARI = [1- Mean ARI treatment / Mean ARI control ] *100; % RARI has a minimum value of zero (no darkening, but if the value is negative the tuber tissue was lighter than the control) and maximum value of 100 (cut tuber surface is completely blackened). The numbers are derived from the mean average reflective intensity of three surfaces cut latitudinally 25, 50 and 75% from the apex of n = 10 tubers per treatment combination. b Values followed by the same letter are not significantly different at P = 0.05 for comparisons of mean RARI values within different P. infestans genotypes of cultivar/ABL combinations and temperature treatments (Tukey Multiple Comparison) ( % )a 12.3 a 9.6 b 6.9 c a b b c d e 15.7 12.7 12.1 10.4 6.3 0.6 Temp- erature (oC) 10 7 3 101 Variety Torridon MSN105-1 MSM171-A MSM051-3 MSL211-3 MSL183-AY Jacqueline- Lee Temper- ature (oC) 3 7 10 3 7 10 3 7 10 3 7 10 3c 7 10 3 7 10 3 7 10 3 7 10 US-1 -3.1 ghb 0.7 b-f c-f -0.1 2.4 a-d e-h -1.2 ab 3.1 e-h -0.6 -1.7 f-h -3.5 h -0.7 e-h 1.4 b-d 2.7 a-c 1.5 b-e 1.3 b-e 1.5 b-e a-d 2.6 -0.5 e-g 0.3 b-f -0.3 d-g 0.8 b-f 0.3 b-f 1.3 b-e 4.6 a US-6 2.5 g fg 4.7 fg 3.0 21.9 ab 22.7 ab 18.5 bc 3.9 fg 2.8 g 1.1 g 8.1 ef 13.1 de 18.1 bc d 21.0 b 18.4 bc 3.8 fg fg 5.2 fg 3.8 fg 3.2 4.3 fg 3.8 fg 13.1 de cd 13.8 27.1 a US-8 0.1 h 5.3 gh 3.6 h 20.8 cd ab 30.7 18.3 c-e 6.9 gh 5.9 gh 4.3 gh c-f 18.1 c 23.3 31.6 a ef 13.8 32.1 a 11.2 fg 14.6 d-f 24.1 bc 3.3 h 5.0 gh 14.7 d-f c-f 17.4 cd 20.7 33.1 a US-10 11.2 b-e a-e 14.3 a-e 11.8 10.0 c-e a-e 14.0 a-e 13.4 18.0 ab 11.0. b-e 8.4 de 12.3 a-e 12.3 b-e 12.8 a-e 8.4 b-e a-e 13.8 a-d 15.1 12.8 a-e a-e 14.0 c-e 10.6 a-c 15.7 12.8 a-e c-e 8.9 a-e 11.3 e 7.5 18.6 a US-11 0.7 h e-g 5.9 4.2 f-h 9.1 d-f c-e 10.7 15.3 a-c 1.8 gh 2.3 gh 1.6 gh 11.0 b-d ab 15.9 17.4 a 3.9 gh 9.4 de 2.2 gh 3.7 gh 1.1 gh 0.8 h 2.0 gh -0.5 h 2.6 gh 10.3 de 12.1 b-d US-14 -1.4 k jk 0.9 9.9 f-k 15.4 d-f 18.2 b-d a 27.1 jk 0.9 i-k 4.4 11.6 e-h 14.4 d-f a 26.7 a 28.0 c-e 17 23 a-c 5.3 h-j 6.8 g-j i-k 4.3 2.3 jk 1.9 jk 6.7 g-j e-g 11.8 c-e 17.8 24.1 ab Funding: MPIC and MSU GREEEN Table 2. Tuber tissue darkening [Mean RARI (%)] in different varieties and advanced breeding lines of potatoes after inoculation with different genotypes of Phytophthora infestans. Tuber tissue darkening caused by different genotypes of P. infestans [Mean RARI ( % )a] MSJ461 a Normalized tuber tissue darkening score expressed % RARI = [1- Mean ARI treatment / Mean ARI control ] *100; % RARI has a minimum value of zero (no darkening, but if the value is negative the tuber tissue was lighter than the control) and maximum value of 100 (cut tuber surface is completely blackened). The numbers are derived from the mean average reflective intensity of three surfaces cut latitudinal at 25, 50 and 75% from the apex of n = 10 tubers per treatment combination. b Values followed by the same letter are not significantly different at P = 0.05 for comparisons of mean RARI values within different P. infestans genotypes of cultivar/ABL combinations and temperature treatments (Tukey Multiple Comparison). The LSD0.05 for comparisons of all RARI values = x.xxx. c Data from 3oC treatment missing for MSL211-3 because of tuber shortage. 1. Kirk, W.W., F. M. Abu-El Samen, J.B. Muhinyuza, R. Hammerschmidt, D.S. Douches, C. A. Thill, H. Groza and A. L. Thompson. 2005. Evaluation of Potato Late blight Management Utilizing Host Plant Resistance and Reduced Rates and Frequencies of Fungicide Applications. Crop Protection 24: 961 - 970. Baker, K.M., W.W. Kirk, J.M. Stein and J.A. Andresen. 2005. Climatic trends and potato late blight risk in the Upper Great Lakes region. HortTechnology 15(3):510-518. Rubio-Covarrubias O.A., D.S. Douches, R. Hammerschmidt, A. daRocha and W.W. Kirk. 2005. Effect of temperature and photoperiod on symptoms associated with resistance to Phytophthora infestans after leaf penetration in susceptible and resistant potato cultivars. Amer. J. Potato Res. 82:153 - 160. Young, G.K., L.R. Cooke, W.W. Kirk, and P. Tumbalam. 2004. Competitive selection of Phytophthora infestans in the US and Northern Ireland. Proceedings of the eighth workshop of an European network for development of an integrated control strategy of 2. 3. 4. 102 5. 6. 7. Funding: MPIC and MSU GREEEN potato late blight. European Journal of Plant Pathology Special Report No.10: 271 -275. Douches, D.S., J. Coombs, K. Felcher and W.W. Kirk. 2004. Field evaluation of foliar resistance to Phytophthora infestans in potato. Amer. J. Potato Res. 81:443-448. Stein, J.M. and W.W. Kirk. 2004. Development of resistance in Phytophthora infestans isolates from several genetic backgrounds to Dimethomorph. Plant Disease 88:930-934. Baker K.M, W.W. Kirk, J. Andresen and J.M. Stein. 2004. A problem case study: Influence of climatic trends on late blight epidemiology in potatoes. Acta Hort (ISHS) 638:37-42. 103 Funding: MPIC and Agchem Industry Evaluation of fungicide programs for potato late blight control: 2007. W. W. Kirk, R. L Schafer, P. Tumbalam and P. Wharton. Department of Plant Pathology, Michigan State University, East Lansing, MI 48824 Potatoes (FL1879, cut seed, treated with Maxim FS at 0.16 fl oz/cwt) were planted at the Michigan State University Muck Soils Experimental Station, Bath, MI on 25 May into two-row by 25-ft plots (34-in row spacing), separated by a five- foot unplanted row and replicated four times in a randomized complete block design. Plots were irrigated as needed with sprinklers and were hilled immediately before sprays began. All rows were inoculated (3.4 fl oz/25-ft row) with a zoospore suspension of Phytophthora infestans [US8 biotype (insensitive to mefenoxam, A2 mating type)] at 104 spores/fl oz on 27 Jul. All fungicides in this trial were applied on a 7-day interval from 5 Jul to 22 Aug (8 applications) with an ATV rear- mounted R&D spray boom calibrated to deliver 25 gal/A (80 p.s.i.) using three XR11003VS nozzles per row. Weeds were controlled by hilling and with Dual 8E (2 pt/A on 25 May), Basagran (2 pt/A on 28 Jun and 11 Jul) and Poast (1.5 pt/A on 11 Jul). Insects were controlled with Admire 2F (20 fl oz/A at planting and on 28 Jun), Sevin 80S (1.25 lb/A on 11 and 25 Jul), Thiodan 3EC (2.33 pt/A on 1 and 21 Aug) and Pounce 3.2EC (8 oz/A on 11 Jul). Plots were rated visually for percentage foliar area affected by late blight on 30 Jul; 15, 22, 29 Aug and 5 Sep [14 days after final application (DAFA), 40 days after inoculation (DAI)] when there was about 100% foliar infection in the untreated plots. The relative area under the disease progress curve was calculated for each treatment from date of inoculation, 30 Jul to 5 Sep, a period of 36 days. Vines were killed with Reglone 2EC (1 pt/A on 6 Sep). Plots (2 x 25-ft row) were harvested on 17 Sep and individual treatments were weighed and graded. Samples of 50 tubers per plot were stored after harvest in the dark 50oF and incidence of tuber late blight was evaluated after 40 days. Meteorological variables were measured with a Campbell weather station located at the farm, latitude 42.8269 and longitude -84.365deg. Maximum, minimum and average daily air temperature (oF) were 88.0, 39.6 and 64.9 and 0-d with maximum temperature >90oF (May); 91.3, 36.1 and 66.6 and 2-d with maximum temperature >90oF (Jun); 95.2, 37.7 and 67.0 and 4-d with maximum temperature >90oF (Jul); 93.4, 36.3 and 68.7 and 4-d with maximum temperature >90oF (Aug); 90.0, 34.1 and 63.4 and 1-d with maximum temperature >90oF (Sep). Maximum, minimum and average daily soil temperature (oF) were 75.1, 53.1 and 65.8 (May); 82.1, 53.2 and 68.2 (Jun); 83.1, 53.7 and 65.3 (Jul); 80.5, 54.5 and 67.1 (Aug); 77.1, 51.3 and 66.4 (Sep). Maximum, minimum and average soil moisture (% of field capacity) were 79.0, 75.2 and 77.3 (May); 91.7, 77.2 and 81.3 (Jun); 82.1, 74.1 and 77.9 (Jul); 98.1, 75.4 and 80.7 (Aug); 76.2, 66.6 and 69.8 (Sep). Precipitation was 0.99 in. (May), 3.91 in. (Jun), 0.80 in. (Jul), 6.18 in. (Aug) and 1.09 in. (Sep). The total number of late blight disease severity values (DSV) over the disease development period was 62 using 90% ambient %RH as a base for DSV accumulation. Plots were irrigated to supplement precipitation to about 0.1 in./A/4 day period with overhead sprinkle irrigation. Table 1 (Set A). Late blight developed steadily after inoculation and untreated controls reached 100% foliar infection by 5 Sep. Up to 40 DAI, all fungicide programs reduced foliar late blight significantly compared to the untreated control and up to 26 DAI were not significantly different from each other. On 29 Aug, 33 DAI, programs with 4.3 to 12.5%, 5.5 to 13.8% and 7.5 to 16.3% foliar late blight were not significantly different. On 5 Sep, 40 DAI, programs with 18.8 to 36.3%, 26.3 to 45.0%, 33.8 to 51.3% and 73.8% foliar late blight were not significantly different. All fungicide programs significantly reduced the average amount of foliar late blight over the season (RAUDPC, 0 to 40 DAI) compared to the untreated. Application programs with RAUDPC values from 3.0 to 6.4, 4.4 to 7.6, 4.7 to 8.1, 6.1 to 9.2 and 9.2 to 11.8 were not significantly different. There were no significant differences in marketable or total yield among treatments. There were no significant differences in the incidence of tuber late blight 60 days after harvest among treatments. Phytotoxicity was not noted in any of the treatments. Table 2 (Set B). Late blight developed steadily after inoculation and untreated controls reached 100% foliar infection by 5 Sep. Up to 40 DAI, all fungicide programs reduced foliar late blight significantly compared to the untreated control but were not significantly different from each other. On 5 Sep, 40 DAI, programs with 12.5 to 30.0%, 16.3 to 36.3% and 28.8 to 37.5% foliar late blight were not significantly different. All fungicide programs significantly reduced the average amount of foliar late blight over the season (RAUDPC, 0 to 40 DAI) compared to the untreated. Application programs with RAUDPC values from 2.1 and 6.2 and 3.6 to 6.6 were not significantly different. There were no significant differences in marketable or total yield among treatments. There were no significant differences in the incidence of tuber late blight 60 days after harvest among treatments. Phytotoxicity was not noted in any of the treatments. 104 Table 1 Set A Foliar late blight (%) Tuber Yield (cwt/A RAUDPCx Max (100) 0 - 40 DAI US1 Total 405 387 358 378 371 330 315 290 314 301 5 Sep 40 DAI 5 DAFAy 28.8 bcd 36.3 bc 28.8 bcd 33.8 bc 30.0 bcd 5 Aug 9 DAIz 0.3 bu 0.8 b 0.3 b 0.3 b 0.3 b 22 Aug 26 DAI 1.0 b 2.8 b 1.8 b 2.3 b 2.8 b 29 Aug 33 DAI 8.3 b 11.3 b 8.8 b 7.5 b 12.5 b 6.5 b 3.6 bc 6.2 bc 2.8 b 2.5 b 0.8 b 0.8 b 33.8 bc 16.3 cd 4.7 bc 6.5 b 4.9 bc 5.3 bc 6.0 bc Treatment and rate/A BravoWS 6SC 1.5 pt (A,B,C,D,E,F,G,H,Iv)…… Equus 720 6SC 1.5 pt (A,B,C,D,E,F,G,H,I)…… Equus ZN 4.17SC 2.16 pt (A,B,C,D,E,F,G,H,I).. Bravo ZN 6SC 1.5 pt (A,B,C,D,E,F,G,H,I)……. Equus 82.5 WDG 1.36 lb (A,B,C,D,E,F,G,H,I).. Dithane DF 2 lb (A,B,C,G,H,I) IR6141 MZ 69WG 2.5 lb (D,E,F)……………… Dithane DF 2 lb (A,B,C,G,H,I) Ridomil Gold MZ 67.9WG 2.5 lb (D,E,F)…….. Dithane DF 2 lb (A,B,C,G,H,I) IR5885 MZ 66WG 1.35 lb (D,E,F)……………. BravoWS 6SC 1.5 pt (A,B,C,G,H,I) IR5885 CTL 76WG 2.5 LB (D,E,F)…………… BravoWS 6SC 1.5 pt (A,B,C,G,H,I) Ridomil Gold Bravo 3.67SC 2.5 pt (D,E,F)…… Tanos 50WDG 0.5 lb + BravoWS 6SC 1.5 pt (A,C,E,G,I); Curzate 76WDG 0.2 lb + BravoWS 6SC 1.5 pt (B,D,F,H)……………….. JE874 2.1SC 0.5 pt + Manzate 75DF 1.5 lb (A,C,E,G,I) Bravo WS 6SC 1.5 pt (B,D,F,H)………………. Untreated............................................................. HSD0.05 z Days after inoculation with Phytophthora infestans, US8, A2. y Days after final application of fungicide. x RAUDPC, relative area under the disease progress curve calculated from day of inoculation to last evaluation of late blight. w Incidence of tuber late blight after storage for 40 days after harvest at 50oF. v Application dates: A= 5 Jul; B= 12 Jul; B= 20 Aug; D= 28 Aug; E= 3 Aug; F= 10 Aug; G= 17 Aug; H= 24 Aug; I = 31 Aug. u Values followed by the same letter are not significantly different at p = 0.05 (Tukey Multiple Comparison). 12.5 d 100.0 a 21.14 2.1 c 32.1 a 4.23 0.0 b 4.8 a 2.94 3.3 b 75.0 a 11.39 1.3 b 32.5 a 36.3 bc 36.3 bc 4.82 37.5 b 6.4 b 6.6 b 0.5 b 0.5 b 3.3 b 3.0 b 37.5 b 10.0 b 11.3 b 10.8 b 11.3 b 10.0 b 1.3 b 2.3 b 0.0 b 0.5 b 288 361 288 361 292 365 344 410 5.7 bc 302 379 Tuber blight (%)w 0.1 0.0 0.0 0.6 0.6 0.0 0.6 0.0 0.0 1.3 0.1 6.2 bc 309 380 302 302 339 339 0.1 0.0 81.3 96.2 1.93 105 Funding: MPIC and Agchem Industry Table 2 Set B. Foliar late blight (%) 5 Aug 9 DAIz 22 Aug 26 DAI 29 Aug 33 DAI 5 Sep 40 DAI 5 DAFAy RAUDPC Max = 100x 0 - 40 DAI Yield (cwt/A) US1 Total Tuber blight (%)w 0.6 0.6 0.0 0.0 0.6 0.6 0.6 0.6 1.3 2.0 b 6.5 cd 3.2 f 350 51.3 c 9.2 bc 0.3 bu 1.0 b 377 415 377 421 368 367 6.1 c-f 8.1 cd 45.0 cd 4.6 ef 4.4 ef 5.5 cd 18.8 f 5.0 b 1.5 b 1.5 b 13.8 bc 0.0 b 0.0 b 2.5 b 3.5 b 1.0 b 1.3 b 306 333 311 13.8 bc 294 297 31.3 c-f 8.3 bcd 26.3 def 12.5 bcd 30.0 def Treatment and rate/A Revus Opti 3.67SC 2.5 pt + 0.125% NIS (A,B,C,Dv); BravoWS 6SC 1.5 pt (E,F,G,H,I)…………………….. Revus Top 4.17SC 5.5 fl oz + 0.125% NIS (A,B,C,D); BravoWS 6SC 1.5 pt (E,F,G,H,I)…………………….. Revus Top 4.17SC 7.0 fl oz + 0.125% NIS (A,B,C,D); BravoWS 6SC 1.5 pt (E,F,G,H,I)…………………….. Quadris Opti 1.6 fl oz (A,C); Revus Top 4.17SC 5.5 fl oz + 0.125% NIS (B,D); BravoWS 6SC 1.5 pt (E,F,G,H,I)…………………….. Forum 3.6SC 6 fl oz + Dithane RS 1.5 lb (A,B,D,F,H); Dithane RS 1.5 lb (C,E,G,I)…………………………... Forum 3.6SC 6 fl oz + COC 8.0 fl oz (A,B,D,F,H); Dithane RS 1.5 lb (C,E,G,I)…………………………... Forum 3.6SC 6 fl oz + Dithane RS 1.5 lb + COC 8.0 fl oz (A,B,D,F,H); Dithane RS 1.5 lb + COC 8.0 fl oz (C,E,G,I)…………. 0.0 b 0.0 b MicroFlo Chlorothalonil 6SC 1.5 pt (A-I)…………..... BravoWS 6SC 1.5 pt (A,C,E,F,G,H,I) Evito 4SC 3.8 fl oz + 0.125% NIS (B,D)…………...… BravoWS 6SC 1.5 pt (A,C,E,F,G,H,I) Evito 4SC 1.9 fl oz + 0.125% NIS (B,D)……………... 0.8 b Polyoxin D 2.5 WDG 2 lb (A-I)………………………. 1.3 b 0.5 b Dithane RS 2.0 lb (A-I)……………………………….. 0.3 b Echo ZN 2.125 pt (A-I)……………………………….. Echo 720 1.5 pt (A-I)………………………………….. 0.3 b SA 010903 4SC 1.5 pt (A-I)…………………………... 0.0 b 4.8 a Untreated........................................................................ 2.64 HSD0.05 z Days after inoculation with Phytophthora infestans, US8, A2. y Days after final application of fungicide. x RAUDPC, relative area under the disease progress curve calculated from day of inoculation to last evaluation of late blight. w Incidence of tuber late blight after storage at 50oF. v Application dates: A= 5 Jul; B= 12 Jul; B= 20 Aug; D= 28 Aug; E= 3 Aug; F= 10 Aug; G= 17 Aug; H= 24 Aug; I = 31 Aug. u Values followed by the same letter are not significantly different at p = 0.05 (Tukey Multiple Comparison). 7.6 cde 11.8 b 5.7 def 5.5 def 6.1 c-f 3.0 f 32.1 a 3.51 12.0 bcd 16.3 b 8.8 bcd 8.3 bcd 11.3 bcd 4.3 d 75.0 a 9.37 45.0 cd 73.8 b 35.0 c-f 35.0 c-f 36.3 c-f 20.0 ef 100 a 20.03 3.3 b 5.5 b 2.3 b 2.3 b 1.5 b 1.0 b 32.5 a 4.86 10.0 bcd 40.0 cde 30.0 def 26.3 def 7.5 bcd 5.8 cd 4.6 ef 3.9 f 1.0 b 1.3 b 323 298 301 0.3 b 2.5 b 388 382 378 6.4 c-f 305 300 302 330 313 298 236 0.0 0.0 0.0 0.0 1.9 0.0 0.0 88.8 97.3 2.79 369 378 376 401 387 375 331 106 Evaluation of fungicide programs for Pythium leak control, 2007. W. W. Kirk, R. L Schafer, P. Tumbalam and P. Wharton. Department of Plant Pathology, Michigan State University, East Lansing, MI 48824 Funding: MPIC and Agchem Industry Potatoes (FL1879, cut seed, treated with Maxim FS at 0.16 fl oz/cwt) were planted at the Michigan State University Muck Soils Experimental Station, Bath, MI on 13 Jun into two-row by 25-ft plots (34-in row spacing), separated by a five-foot unplanted row and replicated four times in a randomized complete block design. Plots were irrigated as needed with sprinklers and were hilled immediately before sprays began. All rows were inoculated (3.4 fl oz/25-ft row) with an oospore suspension of Pythium ultimum (sensitive to mefenoxam) at 102-oospores/fl oz on 20 Jun [7 days after planting (DAP)]. In-furrow and foliar-banded applications were applied with an R&D spray boom delivering 8 gal/A (80 p.s.i.) and using one XR11003VS nozzle per row. Foliar applications were applied with an ATV rear-mounted R&D spray boom calibrated to deliver 25 gal/A (80 p.s.i.) using three XR11003VS nozzles per row. Bravo WS 6SC was applied on a 14-day interval from 27 Jul to 15 Sep (4 applications) to protect against foliar late blight. Weeds were controlled by hilling and with Dual 8E (2 pt/A on 25 May), Basagran (2 pt/A on 28 Jun and 11 Jul) and Poast (1.5 pt/A on 11 Jul). Insects were controlled with Admire 2F (20 fl oz/A at planting and on 28 Jun), Sevin 80S (1.25 lb/A on 11 and 25 Jul), Thiodan 3EC (2.33 pt/A on 1 and 21 Aug) and Pounce 3.2EC (8 oz/A on 11 Jul). Tuber number per plant was rated on 27 Jul and 27 Aug from samples of four plants per plot. Vines were killed with Reglone 2EC (1 pt/A on 21 Sep). Plots (2 x 25-ft row) were harvested on 10 Oct and individual treatments were weighed and graded and tuber number in size grades US-1 and b-grade determined. Samples of 50 tubers/plot were stored in the dark at 50oF and 95% RH for 60 days after harvest and the percentage of tubers with Pythium leak determined. Meteorological variables were measured with a Campbell weather station located at the farm, latitude 42.8269 and longitude -84.365deg. Maximum, minimum and average daily soil temperature (oF) were 75.1, 53.1 and 65.8 (May); 82.1, 53.2 and 68.2 (Jun); 83.1, 53.7 and 65.3 (Jul); 80.5, 54.5 and 67.1 (Aug); 77.1, 51.3 and 66.4 (Sep). Maximum, minimum and average soil moisture (% of field capacity) were 79.0, 75.2 and 77.3 (May); 91.7, 77.2 and 81.3 (Jun); 82.1, 74.1 and 77.9 (Jul); 98.1, 75.4 and 80.7 (Aug); 76.2, 66.6 and 69.8 (Sep). Precipitation was 0.99 in. (May), 3.91 in. (Jun), 0.80 in. (Jul), 6.18 in. (Aug) and 1.09 in. (Sep). Plots were irrigated to supplement precipitation and enhance Pythium leak development to about 0.1 in./A/4 day period with overhead sprinkle irrigation. No treatments had any effect on tuber number per plant measured pre-harvest. All treatments had significantly more US-1 grade tubers per plot at harvest in comparison with the untreated control except IR6141 69WG 0.21 lb/A applied during early senescence (timing D). Treatments with greater than 46.3 b-grade tubers per plot at harvest had significantly more tubers than the untreated control. All treatments had significantly greater US-1 grade yield in comparison with the untreated control. Pythium leak was evident in all plots at harvest but there was no difference in the percentage measured among any treatments. After about 60- days in storage, no treatments had significantly less incidence of tubers with Pythium leak than the untreated control although the incidence was low. Tuber number per plant Tuber number/plot at harvest Yield (cwt/A) Pythium leak (% incidence) 9.6 9.9 109.3 a 83.0 b US-1 202 b 290 a 212 b US-1 80.8 b b-size 61 abc b-size 43.0 abc 27 Jul 27 Aug 9.8 9.6 Treatment and rate/A or rate/1000 row ft Ridomil Gold 4EC 0.42 fl oz/1000 row ft (A)… Ridomil Gold 4EC 0.42 fl oz 1000 row ft (A); Ridomil Gold 4EC 0.42 fl oz/A (B)………….… 10.9 Phostrol 6.69SC 0.66 fl oz/1000 row ft + Ultra Flourish 4SC 0.84 fl oz/1000 row ft (A)… 13.4 Ranman 400SC 0.42 fl oz 1000 row ft (A); Ranman 400SC 2.7 fl oz/A + Silwet SL 2.0 fl oz/A + Phostrol 6.69SC 8.0 pt/A (B); Phostrol 6.69SC 10.0 pt/A (C,D)……………… 12.2 12.9 IR6141 69WG 0.21 lb/A (C,D)……………….. 12.3 IR6141 69WG 0.21 lb/A (C)………………….. IR6141 69WG 0.21 lb/A (D)………………….. 13.4 Untreated............................................................. 13.4 LSD0.05 z Application dates: A= 13 Jun (in-furrow at planting); B= 29 Jun (95% emergence, banded application); C= 25 Jul; D= 8 Aug. y Values followed by the same letter are not significantly different at p = 0.05 (Fishers protected LSD). 86.5 b 81.8 b 83.5 b 75.3 bc 63.8 c 3.04 1.95 13.30 221 b 219 b 221 b 191 b 154 c 36.8 46.8 ab 40.8 abc 36.5 bcd 27.5 d 32.3 cd 66 ab 56 a-d 53 bcd 37 d 44 cd 9.9 9.9 10.1 10.3 10.3 74 a 64 ab 51.0 a 46.3 ab 19.9 12.24 Harvest Storage 0.8 0.7 1.4 0.9 0.9 1.3 0.7 1.7 1.01 0.0 1.0 2.0 1.0 2.0 2.0 1.0 5.0 2.80 107 Potato Insect Biology and Management Report to the Michigan Potato Industry Commission 24 January 2008 Adam M. Byrne, Walter L. Pett, Beth A. Bishop, and Edward J. Grafius Outline. I. Resistance of Colorado potato beetle populations to imidacloprid and thiamethoxam was evaluated for field populations from Michigan, as well as other locations in the Midwest and locations in the northeastern U.S. II. Field insecticide evaluations of registered and experimental insecticides. III. Managing neonicitinoid-resistant Colorado potato beetles with trap crops. I. Resistance of Colorado potato beetle populations to imidacloprid and thiamethoxam. Potato growers across the United States continue to rely heavily on imidacloprid (Admire Pro®) and thiamethoxam (Platinum®, Actara®) for Colorado potato beetle control. In 2005, these compounds were applied to greater than 80% of the acreage in Michigan, Wisconsin, and Minnesota (NASS 2006). This consistent and heavy dependency on these compounds sets the stage for resistance development. Further complicating the issue is the availability of generic imidacloprid formulations; these formulations drive down product cost, which may result in even more field exposure to this compound. All of these reasons strongly support the need to continue monitoring resistance develop and to encourage growers to adopt strong resistance management strategies. Our objectives were to continue gathering data on susceptibility to imidacloprid and thiamethoxam in Colorado potato beetle populations collected from commercial potato fields in Michigan and other regions of the United States. A second objective was to monitor the correlations between imidacloprid and thiamethoxam susceptibility. To accomplish these objectives, 53 Colorado potato beetle populations (32 Michigan populations, 16 populations collected in other states, and five laboratory populations) were bioassayed with imidacloprid and/or thiamethoxam. Methods During 2007, 32 Colorado potato beetle populations were collected from two different Michigan counties (Mecosta and Montcalm). Cooperators also provided one population from Delaware, two populations from Idaho, three populations from Minnesota, four populations from Maine, and six populations from Wisconsin. Five laboratory strains were also tested (Table I.1). 108 Colorado potato beetle adults were either kept at room temperature (25±1° C) and fed foliage daily or, for longer term storage, kept in controlled environment chambers (11±1° C) and fed weekly. Beetles were treated with 1 µl of acetone/insecticide solution of known concentration applied to the ventral surface of the abdomen using a 50 µl Hamilton® microsyringe. Following treatment, beetles were placed in 100 mm diameter petri dishes lined with Whatman® No. 1 filter paper and provided with fresh potato foliage. They were kept at 25±1° C and the foliage and filter paper were checked daily and changed as needed. A preliminary screen was conducted on most populations (for populations tested in previous years, screening was sometimes not necessary) to determine relative susceptibility to imidacloprid and thiamethoxam by testing 10 beetles each with one concentration of insecticide/acetone solution. Based on the results from these screens, a range of five concentrations was selected for each population to be assayed and each bioassay was replicated up to three times. In each replicate, 10-15 beetles were treated with each concentration (four to five beetles per dish and two to three dishes per concentration). Beetle response was assessed 7 days post treatment. A beetle was classified as dead if its abdomen was shrunken, it did not move when its legs or tarsi were pinched, and its elytra were darkened. Beetles that had died due to Beauvaria sp. infection were excluded from analysis; these beetles were easily recognized by their pale petrified appearance or presence of white filamentous fungi. A beetle was classified as walking and healthy if it was able to grasp a pencil and walk forward normally. A beetle was classified as poisoned if its legs were extended and shaking, it was unable to right itself or grasp a pencil, and it was unable to walk forward normally at least one body length. Dead and poisoned beetle numbers were pooled for analysis. Data were analyzed using standard log-probit analysis (SAS® System v9.1.3). Results The imidacloprid LD50 value (dose lethal to 50% of the beetles) for the susceptible laboratory strain (New Jersey) was 0.036 µg/beetle. The LD50 values for imidacloprid ranged from 0.034 µg/beetle (Anderson Bros. field 7) to 1.563 µg/beetle (Sackett Potatoes, field 155) for Michigan populations (Figure I.1A) and from 0.009 µg/beetle (Idaho and Kimberly, ID) (Figure I.2.A) to 3.536 µg/beetle (Delaware, DE) (Table I.2) for out-of-state populations. Significant levels of resistance to imidacloprid were again present in Michigan. Beetles from Sackett Potatoes, fields 26-29 were 32-fold resistant to imidacloprid, compared to the susceptible strain. An additional five fields on the home farm (field 1, field 4, fields 5-8&31-32, field 12, and field 25) were also greater than 20-fold resistant to imidacloprid. In total, 14 samples were tested with imidacloprid from the Sackett Potatoes home farm, all but two were greater than 10-fold resistant to imidacloprid (Figure I.1.B). 109 In 2007, 14 additional sites away from the Sackett Potatoes home farm showed greater than 20-fold resistance to imidacloprid, contrasted with only three sites in 2006, and all Michigan samples had significantly higher LD50 values than the susceptible New Jersey strain. These sites were all within approximately 10-12 km from Sackett Potatoes home farm, but in several different directions (i.e. Paul Main Rodney Farm to the northwest, Paul Main HB-S site to the southwest, and Sackett Potatoes fields 101-103 to the northeast). The overall LD50 values were lower than last year; this year’s highest LD50 value was 1.563 µg/beetle (Sackett Potatoes field 155) compared to last year’s 3.244 µg/beetle (Sackett Potatoes fields 47&48), but the proportion of samples greater than 10- fold resistant was up from 50% in 2006 to 67% in 2007. The lower LD50 values detected throughout the region is a positive sign, but needs to be contrasted with the increase in sites showing elevated levels of resistance. Continued monitoring of these sites, along with testing of new sites surrounding them, will be integral in our tracking and understanding of the spread of resistance and the impacts of the various control approaches being used (ie. trap crops, alternate insecticides, etc.). Two populations tested from Maine showed high levels of resistance to imidacloprid, despite avoidance of neonicotinoid insecticides at those sites for the past four growing seasons. Simply switching to a new compound won’t be enough to suppress a resistance problem, this example drives home the importance of managing available compounds wisely, before problems develop. Populations tested from Wisconsin and Minnesota all had significantly greater LD50 values compared to the susceptible strain, and for the first time, greater than 10-fold resistance was detected in Wisconsin. The two populations tested from Idaho were very susceptible, consistent with results found in previous years. The thiamethoxam LD50 value for the susceptible laboratory strain (New Jersey) was 0.056 µg/beetle; this value is greater than last year’s 0.032 µg/beetle, but was statistically similar based upon overlapping confidence intervals. The LD50 values for thiamethoxam ranged from 0.077 µg/beetle (Sackett Potatoes field 3) to 0.292 µg/beetle (Paul Main field HB-YN) for Michigan populations (Figure I.3.A) and from 0.045 µg/beetle (Aroostook, ME) to 0.383 µg/beetle (Delaware, DE) for out-of-state populations (Figure I.2.B, Table I.3). No Michigan populations had greater than 10-fold resistance to thiamethoxam. However, of the 34 sites sampled, all but four had LD50 values significantly higher than the susceptible New Jersey strain. The thiamethoxam results mirrored those of imidacloprid, overall resistance values were lower this year, but the proportion of sites exhibiting significant differences from the susceptible strain increased from the previous year. Susceptibility to imidacloprid (as measured by LD50) in field-collected Colorado potato beetle populations was highly correlated with susceptibility to thiamethoxam (Figure I.4). This result was also found in 1998, 1999, 2000, 2002, 2003, 2004, 2005, and 2006 (e.g. Grafius et al. 2004, 2005; Byrne et al. 2006, 2007). This high correlation is a strong 110 indicator that alternation between imidacloprid and thiamethoxam would not be an effective or wise management technique. The Evans and NY-Sel strains have been selected for imidacloprid resistance, while Hadley and Sloth were selected for resistance to thiamethoxam. Adults from each generation were selected with their corresponding compound, using doses causing 30- 90% mortality. Survivors from selections were used to maintain the laboratory strains. Bioassays are conducted roughly every third generation, allowing us to follow resistance development under a high selection pressure scenario. Table I.1. Colorado potato beetle populations tested for susceptibility to imidacloprid and thiamethoxam in 2007. Michigan populations Andersen Brothers Farm Adults were collected by Mark Otto, AgriBusiness Consultants, Inc. from commercial potato fields in Montcalm Co., MI. Field 7 Adults were collected on 7 July 2007. Fields 41&43 Adults were collected on 19 July 2007. Montcalm Farm Overwintered adults were collected on 12 June 2007 and summer adults on 10 July 2007 from the Michigan State University Montcalm Potato Research Farm in Entrican, MI. Paul Main Farm Adults were collected by Mark Otto, AgriBusiness Consultants, Inc. from commercial potato fields in Mecosta Co. Field ALVA Adults were collected on 1 June 2007. Field HB-HEN Adults were collected on 5 July 2007. Field HB-NS Adults were collected on 5 June 2007. Field HB-S Adults were collected on 31 May 2007. Field HB-YN Adults were collected on 7 July 2007. Field KR-GR Adults were collected on 17 July 2007. Field PC Home Adults were collected on 21 August 2007. Field R1 Overwintered adults were collected on 14 June 2007 and summer adults on 11 July 2007. Field R7 Overwintered adults were collected on 31 May 2007 and summer adults on 12 July 2007. Field R8 Overwintered adults were collected on 31 May 2007 and summer adults on 12 July 2007. Sackett Acres Field 12 Adults were collected on 17 July 2007 by Mark Otto, AgriBusiness Consultants, Inc., from a commercial potato field in Mecosta Co., MI. Sackett Potatoes Adults were collected by Mark Otto, AgriBusiness Consultants, Inc., and Michigan State University researchers from commercial potato fields in Mecosta Co., MI. Field 1 Overwintered adults were collected on 9 June 2007 and summer adults on 17 July 2007. Field 3 Overwintered adults were collected on 6 June 2007 and summer adults on 17 July 2007. Field 4 Adults were collected on 17 July 2007. 111 Table I.1 cont’d. Colorado potato beetle populations tested for susceptibility to imidacloprid and thiamethoxam in 2007. Fields 5-8 & 31-32 Adults were collected on 22 August 2007. Field 12 Adults were collected on 5 July 2007. Field 15 Adults were collected on 29 May 2007. Field 18 Adults were collected on 11 June 2007. Field 21 Adults were collected on 22 May 2007. Field 25 Adults were collected on 17 July 2007. Fields 26-29 Adults were collected on 23 August 2007. Fields 41-42 Adults were collected on 22 August 2007. Field 43 Adults were collected on 17 July 2007. Fields 54-55 Overwintered adults were collected on 11 June 2007 and summer adults on 18 July 2007. Fields 86 Adults were collected on 17 July 2007. Field 94 Adults were collected on 5 July 2007. Fields 101-102 Adults were collected on 5 June 2007. Field 103 Adults were collected on 10 July 2007. Field 155 Adults were collected on 17 July 2007. Out-of-state populations Aroostook, Maine Adults were collected on 13-14 August 2007 by Gary Sewell, University of Maine, from untreated potato research plots near Presque Isle, ME. Becker, Minnesota Adults were collected on 29 August 2007 by Brian McCornack, University of Minnesota, from a commercial potato field near Becker, MN. Bridgewater, Maine Adults were collected on 9 August 2007 by Jim Gerritsen, Wood Prairie Farm, from an organic potato field, treated with copper hydroxide, near Bridgewater, ME. C-05, Wisconsin Adults were collected on 7 June 2007 by Russell L. Groves, University of Wisconsin-Madison. Delaware, Delaware Adults were collected on 12 July 2007 by Joanne Whalen, University of Delaware, from a commercial potato field, treated with Actara, Kryocide, and Spintor, near Little Creek, DE. Fryeburg-140A, Maine Adults were collected on 19 June 2007 by Andrei Alyokhin, University of Maine, from a commercial potato field near Fryeburg, ME. Fryeburg-Jimmy Hill, Maine Adults were collected on 19 June 2007 by Andrei Alyokhin, University of Maine, from a commercial potato field near Fryeburg, ME. H-02, Wisconsin Adults were collected on 7 June 2007 by Russell L. Groves, University of Wisconsin-Madison. H-11, Wisconsin Adults were collected on 14 June 2007 by Russell L. Groves, University of Wisconsin-Madison. H-41, Wisconsin Adults were collected on 7 June 2007 by Russell L. Groves, University of Wisconsin-Madison. H-53, Wisconsin Adults were collected on 7 June 2007 by Russell L. Groves, University of Wisconsin-Madison. 112 Table I.1 cont’d. Colorado potato beetle populations tested for susceptibility to imidacloprid and thiamethoxam in 2007. Hancock, Wisconsin Adults were collected on 9 July 2007 by Russell L. Groves, University of Wisconsin-Madison, from untreated potatoes at the Hancock Agricultural Experiment Station, Waushara Co., WI. Idaho, Idaho Adults were collected on 14 June 2007 by Juan Alvarez, University of Idaho, from a commercial potato field near Kimberly, ID. Kimberly, Idaho Adutls were collected on 14 June 2007 by Juan Alvarez, University of Idaho, from a commercial potato field near Kimberly, ID. Minnesota, Minnesota Adults were collected in mid-August 2007 by Ian MacRae, University of Minnesota. Sand Plains, Minnesota Adults were collected on 15 August 2007 by Brian McCornack, University of Minnesota, from the Sand Plain Research Farm near Becker, MN. Laboratory strains Evans Collected from Montcalm Co., MI in summer 1997. Adults from most generation have been selected with imidacloprid doses targeting 60-80% mortality. Hadley Collected from Hadley, MA in July 2003. Adults from each generation have been selected with thiamethoxam doses targeting 60-80% mortality. New Jersey Adults obtained from the Phillip Alampi Beneficial Insects Rearing Laboratory, New Jersey Department of Agriculture. NY-Select Collected from Long Island, NY in 1997. Adults from most generations selected with imidacloprid doses targeting 60-80% mortality. Sloth Collected from Sackett Potatoes, Mecosta Co., MI in summer 2005. Adults from each generation have been selected with thiamethoxam doses targeting 60-80% mortality. 113 A. Michigan populations B. Sackett Potatoes Home Farm Figure I.1. Susceptibility of Michigan field populations of Colorado potato beetle to imidacloprid. The SP Home Farm value in figure A is an average of all populations presented in figure B. An asterisk (*) denotes values significantly greater than the susceptible strain. 00.511.5AB-41&43AB-7SA 12P. Main KR-GRP. Main AlvaP. Main HB-SP. Main HB-HENP. Main HB-NSP. Main HB-YNMontcalm (winter)Montcalm (summer)SP 54 (summer)SP 54-55 (winter)SP 86SP 94SP Home Farm (avg)P. Main PC HomeP. Main R1 (winter)P. Main R1 (summer)P. Main R7 (winter)P. Main R7 (summer)P. Main R8 (winter)P. Main R8 (summer)SP 101-102SP 103SP 155LD50 (!g/beetle)1.563******* ************** **10x susceptible00.511.5SP 1 (winter)SP 1 (summer)SP 3 (winter)SP 3 (summer)SP 4SP 5-8&31-32SP 12 SP 15SP 18SP 21SP 25SP 26-29SP 41-42SP 43LD50 (!g/beetle)**************10x susceptible114 A. Imidacloprid B. Thiamethoxam Figure I.2. Susceptibility of field populations of Colorado potato beetle to imidacloprid (A) and thiamethoxam (B). Michigan values presented as a range from lowest to highest value. An asterisk (*) donotes values significantly greater than the susceptible strain. 00.511.5ME1ME2ME3ME4MIWI1WI2WI3WI4WI5MN1MN2MN3MN2ID1ID2LD50 (!g/beetle)1.563**10x susceptible* ***********00.20.40.60.81ME1ME2ME3ME4DEMIWI1WI2WI3WI5MN1MN2MN3ID2LD50 (!g/beetle)10x susceptible********115 LD50 95% fiducial limits 0.034 0.7602 0.1511 0.3311 0.2251 0.019-0.047 0.503-1.074 0.091-0.354 0.251-0.449 0.167-0.289 Table I.2. LD50 values (µg/beetle) and 95% fiducial limits for Colorado potato beetle populations treated with imidacloprid at 7 days after treatment. Michigan populations Andersen Bros Field 7 Andersen Bros Fields 41&43 Montcalm Farm (winter) Montcalm Farm (summer) Montcalm Farm (lab reared) Paul Main Farm Field ALVA Field HB-HEN Field HB-NS Field HB-S (winter) Field HB-S (lab-reared) Field HB-YN Field KR-GR Field PC Home Field R1 (winter) Field R1 (summer) Field R7 (winter) Field R7 (summer) Field R7 (lab-reared) Field R8 (winter) Field R8 (summer) Sackett Acres Field 12 Sackett Potatoes Field 1 (winter) Field 1 (summer) Field 3 (winter) Field 3 (summer) Field 3 (lab-reared) Field 4 Fields 5-8 & 31-32 Field 12 Field 15 Field 18 Field 25 0.159-0.337 0.617-0.960 0.081-0.297 0.298-0.801 0.439-0.864 0.374-1.125 0.196-0.329 0.039-0.673 0.126-0.214 0.621-0.980 0.338-0.696 0.467-0.624 0.403-1.106 0.233-0.828 0.320-0.504 0.121-0.380 0.242-0.370 0.612-0.934 0.205-0.648 0.331-0.585 0.389-0.548 1.097-1.815 0.659-1.136 0.535-1.310 0.471-0.643 8.86E-42-0.582 0.644-0.967 0.2221 0.8002 0.1891 0.5502 0.6832 0.7892 0.2411 0.426 0.1701 0.8202 0.4462 0.5452 0.6192 0.3421 0.3942 0.1781 0.3041 0.7912 0.3962 0.4722 0.4632 1.3792 0.8252 1.0002 0.5501 0.339 0.7832 116 0.111-0.174 0.159-0.292 0.089-0.251 0.083-0.735 0.400-1.599 0.954-1.780 0.330-0.483 * * LD50 1.1532 0.7192 0.4922 0.1521 0.3521 0.4772 0.4132 0.4172 0.9042 1.5632 0.698-4.455 0.540-0.893 0.387-0.592 0.090-0.206 0.237-0.500 0.226-0.834 0.289-0.513 0.289-0.813 0.763-1.073 1.290-1.934 Table I.2. cont’d. LD50 values (µg/beetle) and 95% fiducial limits for Colorado potato beetle populations treated with imidacloprid at 7 days after treatment. 95% fiducial limits Sackett Potatoes cont’d Fields 26-29 Fields 41-42 Field 43 Fields 54-55 (winter) Fields 54-55 (summer) Field 86 Field 94 Fields 101-102 Field 103 Field 155 out-of-state populations Aroostook, ME Becker, MN Bridgewater, ME C-05, WI Delaware, DE Fryeburg-140A, ME Fryeburg-Jimmy Hill, ME H-02, WI H-11, WI H-41, WI H-53, WI Hancock, WI Idaho, ID Kimberly, ID Minnesota, MN Sand Plains, MN laboratory strains Evans Hadley New Jersey Sloth 1 significantly greater than LD50 value for susceptible New Jersey strain 2 greater than 10 times the LD50 value for susceptible New Jersey strain 0.141 0.2241 0.1261 0.4642 3.536 1.1182 1.3522 0.4122 0.135 0.5042 0.4342 0.1981 0.009 0.009 0.0751 0.1931 0.204-0.755 0.338-0.517 0.104-3.575 0.004-0.011 0.006-0.011 0.059-0.090 0.082-0.505 5.8812 18.7482 0.036 1.0332 3.808-7.923 15.530-29.583 0.032-0.042 0.869-1.308 117 A. Michigan populations B. Sackett Potatoes Home Farm Figure I.3. Susceptibility of Michigan field populations of Colorado potato beetle to thiamethoxam. The SP Home Farm value in figure A is an average of all populations presented in figure B. An asterisk (*) denotes values significantly greater than the susceptible strain. 00.20.40.60.81AB 41&43SA 12P. Main KR-GRP. Main AlvaP. Main HB-SP. Main HB-HENP. Main HB-NSP. Main HB -YNMontcalm (winter)Montcalm (summer)SP 54-55 (winter)SP 54 (summer)SP 86SP 94SP Home Farm (avg)P. Main R1P. Main R7P. Main R8 (winter)P. Main R8 (summer)SP 101-102SP 103SP 155LD50 (!g/beetle)10x susceptible************ ********00.20.40.60.81SP 1 (winter)SP 1 (summer)SP 3 (winter)SP 3 (summer)SP 4SP 5-8&31-32SP 12SP 15SP 18SP 21SP 25SP 41-42SP 43LD50 (!g/beetle)10x susceptible**********118 95% fiducial limits 0.129-0.304 0.066-0.106 0.121-0.182 * LD50 0.1951 0.0821 0.1461 0.070-0.118 0.064-0.339 0.095-0.127 0.192-0.317 0.249-0.340 0.063-0.120 0.0961 0.2241 0.1101 0.2421 0.2921 0.085 0.113 0.0851 0.1281 0.1011 0.1671 0.1181 Table I.3. LD50 values (µg/beetle) and 95% fiducial limits for Colorado potato beetle populations treated with thiamethoxam at 7 days after treatment. Michigan populations Andersen Bros Fields 41&43 Montcalm Farm (winter) Montcalm Farm (summer) Paul Main Farm Field ALVA Field HB-HEN Field HB-NS Field HB-S (winter) Field HB-YN Field KR-GR Field PC Home Field R1 (winter) Field R7 (summer) Field R8 (winter) Field R8 (summer) Sackett Acres Field 12 Sackett Potatoes Field 1 (winter) Field 1 (summer) Field 3 (winter) Field 3 (summer) Field 4 Fields 5-8 & 31-32 Field 12 Field 15 Field 18 Field 21 Field 25 Fields 41-42 Field 43 Fields 54-55 (winter) Fields 54-55 (summer) 0.060-0.177 0.138-0.204 0.061-0.094 0.039-0.246 0.182-0.263 0.108-0.209 0.240-0.329 0.127-0.167 0.118-0.156 0.102-0.154 0.146-0.202 0.065-0.179 0.174-0.247 0.076-0.113 0.119-0.177 0.112 0.1701 0.077 0.163 0.2241 0.1371 0.2831 0.1461 0.1351 0.1281 0.1721 0.1121 0.2081 0.0951 0.1471 0.064-0.106 0.097-0.159 0.084-0.120 0.140-0.199 0.068-0.206 119 LD50 0.1721 0.1601 0.1471 0.2421 0.2711 0.148-0.204 0.138-0.186 0.129-0.171 0.202-0.290 0.230-0.317 0.045 0.076 0.075 0.2031 0.3831 0.2041 0.2931 0.1361 0.1761 0.1021 0.011 0.054 0.096 Table I.3. cont’d. LD50 values (µg/beetle) and 95% fiducial limits for Colorado potato beetle populations treated with thiamethoxam at 7 days after treatment. 95% fiducial limits Sackett Potatoes cont’d Field 86 Field 94 Fields 101-102 Field 103 Field 155 out-of-state populations Aroostook, ME Becker, MN Bridgewater, ME C-05, WI Delaware, DE Fryeburg-140A, ME Fryeburg-Jimmy Hill, ME H-02, WI H-41, WI Hancock, WI Kimberly, ID Minnesota, MN Sand Plains, MN laboratory strains Evans Hadley New Jersey NY-Sel Sloth 1 significantly greater than LD50 value for susceptible New Jersey strain 2 greater than 10 times the LD50 value for susceptible New Jersey strain 0.033-0.055 0.063-0.089 0.053-0.132 0.159-0.247 0.268-0.494 0.149-0.245 0.238-0.343 0.113-0.161 0.148-0.208 0.083-0.128 0.008-0.014 0.043-0.062 0.052-0.212 0.5972 4.4532 0.056 0.2051 0.2481 0.464-0.732 3.597-5.722 0.048-0.063 0.159-0.256 0.216-0.287 120 Figure I.4. Correlation between susceptibility to imidacloprid and thiamethoxam for all field populations tested in 2007 (n=48). II. Field insecticide evaluations of registered and experimental insecticides. Evaluation of registered and potential insecticides for control of Colorado potato beetle provides data on comparative effectiveness of products and data to support future product registrations. Methods. Thirteen insecticide treatments plus an untreated check (Table II.1) were tested at the Michigan State University Montcalm Research Farm, for control of CPB. ‘Atlantic’ seed pieces were planted 12 in. apart, with 34 in. row spacing on 11 May 2007. Treatments were replicated four times in a randomized complete block design. Plots were 50 ft long and three rows wide. Admire Pro, Platium, and V10170 treatments were applied in-furrow at planting using a single nozzle hand-held boom (30 gpa, 30 psi). Foliar treatments were first applied at greater than 50% egg hatch on 14 June. Subsequent first-generation sprays for most treatments were applied on 21 June, 28 June and 5 July, depending on treatment (Table II.1). y = 0.1539x + 0.0699R2 = 0.644200.10.20.30.400.20.40.60.811.21.41.6imidacloprid LD50 (!g/beetle)thiamethoxam LD50 (!g/beetle)121 Post-spray counts of CPB Adults, egg masses, small larvae (1st and 2nd instars), and large larvae (3rd and 4th instars) on five randomly selected plants from the middle row of each plot were made 5 to 6 days after each foliar application. On 7 September, the middle row of each plot was harvested mechanically and the total tuber weight was recorded. Data was analyzed using two-way ANOVA (treatment and block) and significant differences were determined with Fisher’s Protected LSD test (p=0.05). Results. The seasonal average number of large larvae was significantly lower in treated plots compared to untreated plots (Table II.1). All treatments resulted in significantly fewer large larvae than the untreated plots. The insecticide treatments kept large larvae below the economic threshold of 1 to 2 large larvae per plant compared to 18 large larvae per plant in the untreated plots. The seasonal average number of egg masses and small larvae, included larvae that had recently hatched and were still on the egg mass, resulting in high variability in these results. All treatments resulted in significantly higher yields than the untreated plots (Table II.2). The 2007 insecticide evaluations tested several non-neonicotinoid insecticides, and combinations of non-neonicotinoid insecticides, all proved to be to effective for the control of CPB. Although these chemicals may have cost limitations, restrictions in number of applications, and timing of application, they are valuable chemicals to slow CPB resistance to neonicotinoids. 122 Rate Adults 5.35 oz/A Egg Masses 0.3 def Large Larvae 0.1a 0.1a 0.0a 0.0a 0.6a 0.5a 1.0a 1.0a 0.0a 1.1a 0.6a 0.6a 0.0a 17.9b 0.4a 0.7a 0.3a 0.3a 0.2a 0.5a 0.2a 0.4a Small Larvae 10.7 bcd 11.9 cd 12.7 de 11.4 bcd 11.0 bcd 10.0 b 11.4 bcd 10.4 bc 0.1 abcd 0.2 bcde 0.1 abcd 0.1 abc 0.2 abcd 0.2 abcd 0.2 abcd 11.0 bcd 0.04ab 0.5 g 14.5 e 0.4 fg 11.0 bcd 0.3 efg 11.0 bcd 11.5 bcd 0.02a 0.06abc 11.1 bcd 2.6 oz/A 5.5 oz/A 8.0 fl oz/A 2.0 oz/A 3.0 oz/A 4.5 fl oz/A 4.5 fl oz/A 6.0 fl oz/A 8.0 fl oz/A 0.3a 12.0 fl oz/A 1.0a 6.0 fl oz/A 0.4a 8.0 fl oz/A 0.6a 12.0 fl oz/A 0.3a ------ 2.2 b Table II.1. The seasonal average number of first generation Colorado potato beetle adults, egg masses, small larvae, and large larvae per plant. Treatment/ formulation A15645 (Chili)6 A9545C6 Actara5 Admire Pro1 Altocor4 Altocor4 Alverde5 Alverde then Spintor5 Platium1 Rimon5 Rimon2 Rimon3 V101701 Untreated Average numbers within a column followed by a different letters are significantly different (P,0.05, Fisher’s Protected LSD). Data transformed for analysis with log (x+1), presented in non-transformed units. 1Treatments applied in-furrow at planting May 11, 2007 2Treatments applied: 14 Jun, 21 Jun, 28 Jun, 5 Jul 3Treatments applied: 14 Jun, 21 Jun, 28 Jun 4Treatments applied: 14 Jun, 28 Jun, 5 Jul 5Treatments applied: 14 Jun, 28 Jul 6Treatments applied: 14 Jun 123 5.35 oz/A 2.6 oz/A 5.5 oz/A 8.0 fl oz/A 2.0 oz/A 3.0 oz/A 4.5 fl oz/A 4.5 fl oz/A 6.0 fl oz/A 8.0 fl oz/A 12.0 fl oz/A 6.0 fl oz/A 8.0 fl oz/A 12.0 fl oz/A ------ 78.9 ef 76.8 def 56.5 cdef 50.8 cd 81.8 f 19.0a Total Harvest Weight (lbs)/ 50 row ft. 58.1 cdef 71.1 cdef 68.9 cdef 68.6 cdef 58.1 cdef 55.4 cde 51.0 cd 46.2 bc Table II.2. The average yield (lbs/50 row feet) of harvested ‘Atlanta’ potatoes. Treatment/formulation Rate A15645 (Chili)6 A9545C6 Actara5 Admire Pro1 Altocor4 Altocor4 Alverde5 Alverde then Spintor5 Platium1 Rimon5 Rimon2 Rimon3 V101701 Untreated Average numbers within a column followed by a different letters are significantly different (P,0.05, Fisher’s Protected LSD). Data transformed for analysis with log (x+1), presented in non-transformed units. 1Treatments applied in-furrow at planting May 11, 2007 2Treatments applied: 14 Jun, 21 Jun, 28 Jun, 5 Jul 3Treatments applied: 14 Jun, 21 Jun, 28 Jun 4Treatments applied: 14 Jun, 28 Jun, 5 Jul 5Treatments applied: 14 Jun, 28 Jul 6Treatments applied: 14 Jun 124 III. Managing neonicitinoid-resistant Colorado potato beetles with trap crops. Now that neonicitinoid resistance is present in CPB populations from Michigan, we must help growers manage resistant CPB without increasing the resistance or encouraging dispersal of resistant individuals (thus spreading the resistance). For the past three years we have used trap crops and alternative (non-neonicitinoid) insecticides in a crop rotation system to manage resistant CPB and limit dispersal. In 2005 we attracted over 100,000 overwintered adult CPB with an-early planted trap crop. The trap crop was disced down on 1 Jul, before the larvae could mature and enter the ground to pupate. Alternative insecticides were applied only to the trap crop and cost to the grower was less than $600, compared with a cost of $4,500 for treatment of the entire 75-acre potato field. In 2006 we again used trap crops and alternative insecticides to manage neonicitinoid-resistant CPB at this location. Four to eight rows of potatoes were planted early (mid-April) along 5 edges of a rotated field (planted to corn in 2006, planted to potatoes in 2005). The weather conditions in 2006 were not ideal for using trap crops to manage CPB. Cool weather in early May delayed potato growth and Colorado potato beetle emergence. Late in May the weather warmed to much above-normal temperatures. Potatoes (both trap crop and main crop) grew quickly; by mid-June there was no difference in size (or attractiveness) between the trap crop and the main potato field. In addition, the high temperatures meant that CPB emerged from overwintering quickly and in large numbers and many flying beetles were observed. Such conditions are ideal for CPB dispersal. However, the trap crop concentrated most of the beetles during their emergence period and the grower was able to spot-treat the trap crop and the potato field edges with alternative insecticides to control CPB. More marked beetles were found in the trap crop that they were released into than were found in the main potato field. Beetles may have dispersed out of the sampling area, but remained in the trap crop, but these areas were not inspected for marked beetles. The grower was able to control CPB by using a reduce rate of Admire Pro in most of the new potato fields (some fields had no neonicitinoids) at planting. Besides the spot-treatments of the trap crop, the grower used treatments of Agri-Mek in June and July to sections of the fields where needed In 2007 we again tested trap crops and alternative insecticides for control of resistant CPB. We included different potato varieties in the trap crop to test their relative attractiveness to CPB. Methods. A trap crop consisting of four rows of potatoes (cv ‘Atlantic’) was planted Apr 23 along the edges of fields that were in potatoes in 2006 and were to be planted in corn in 2007. Fields to be planted in potatoes to 2007 were directly across from the trap crop (Figure III.1). On May 3 we established plots within the trap crop; each plot was 10 m long. In each plot we hand-planted a fifth row of trap crop along the inner edge of the existing rows (nearest to the corn so that beetles emerging from the overwintering and walking toward the main crop would encounter this row first. The fifth row consisted of one of three different potato varieties: Atlantic, Dakota Diamond, or NewLeaf. We planted each variety in each of nine plots. The main potato fields were not planted until May 7 - 125 11. Trap crops emerged well before the main crop and remained larger (and more attractive to beetles) thorough June. Figure III.1. Map of 2007 trap crop study. Potatoes in the trap crop plots were searched for Colorado potato beetles one to two times per week from May 25 to June 26, 2007. Areas in the main crop (potatoes 2007) opposite the trap crops were also searched periodically during this period. To examine the dispersal of beetles from the trap crop we marked and released adult CPB in each plot. Adults were either marked in the field or were collected and transported back to the lab for marking. Beetles were marked on the elytra with felt tipped paint pens (DecoColor, Uchida of America Corp). Marked beetles were released next to the 5th trap crop row (which consisted of Dakota Diamond, Atlantic or NewLeaf potatoes). The color and pattern of each marking denoted the date and location of their release. Beetles were released on 25 May and another group of beetles were released on 6 June. Each plot in the trap crop was searched for marked beetles on May 30, June 6, June 12 and June 21. When encountered, the color and pattern of each marked beetle found was recorded, dead beetles were collected, but live beetles were left in the plot. The main potato field just opposite each sampling area was also searched for marked beetles on June 12 and 14 and all marked beetles encountered were collected. Results: Trap crops attracted overwintered potato beetles emerging from diapause as they walked from the corn to the potato field. Between mid-May and mid-June, beetle densities in the trap crop ranged from ca 10 to 16 beetles per meter of row (Figure III.2). Beetle density peaked on May 30 and then decreased. Unlike in 2006, beetles tended to remain in the trap crop and few dispersed to the main crop; few beetles, marked or unmarked, were 126 found in the main potato field. Temperatures were more moderate in 2007 compared with those in 2006, and the trap crop remained larger than the main crop throughout the spring and was thus more attractive to CPB. The relatively lower temperatures did not promote much beetle flight. The grower made one application of non-neonicitinoid insecticide (Spintor) to the trap crop rows on June 5. This killed beetles before they could disperse to the main crop and kept the trap crop from getting defoliated. Spintor was again applied to trap crop rows and sections of the main potato field, as needed, on July 3. The trap crop remained attractive until late June. Figure III.2. Number of overwintered Colorado potato beetle adults captured in trap crop plots with different potato varieties planted in the last row. Almost no marked beetles were found in the main potato crop. Many marked beetles were found in the trap crop (Figure III.3). This proportion varied depending on the potato variety in the plot. Variety is one component of the trap crop system that can be manipulated to maximize effectiveness. In summary, trap crops attracted and retained overwintered Colorado potato beetles and kept them from colonizing the main potato field. The growing conditions in 2007 enabled the trap crop to remain larger than, and thus more attractive to beetles than, the main potato crop for a considerable period in the spring. Beetles in the trap crop were controlled with targeted applications of non neonicitinoid insecticides. Trap crops reduced selection pressure for insecticide resistance and discouraged dispersal of resistant beetles. 127 Figure III.3. Proportion of marked beetles released on 25 May into trap crops of different potato varieties that were recaptured in the same plot. Literature citations: Byrne, A., W. Pett, E. Grafius, and B. Bishop. 2006. Potato insect biology and management. Michigan Potato Research Report 37:106-125. Mich. Agric. Exper. Station, East Lansing, Michigan. Byrne, A., W. Pett, E. Grafius, and B. Bishop. 2007. Potato insect biology and management. Michigan Potato Research Report 38:120-142. Mich. Agric. Exper. Station, East Lansing, Michigan. Grafius, E., B. Bishop, W. Pett, A. Byrne, and E. Bramble. 2004. Potato insect biology and management. Michigan Potato Research Report 35:96-109. Mich. Agric. Exper. Station, East Lansing, Michigan. Grafius, E., W. Pett, B. Bishop, A. Byrne, and E. Bramble. 2005. Potato insect biology and management. Michigan Potato Research Reprot 36:42-56. Mich. Agric. Exper. Station, East Lansing, Michigan. Nat. Agric. Stats. Serv. 2006. p. 45-54 in http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsFC//2000s/2006/AgriChemUsFC- 05-17-2006.pdf. SAS Institute. 2003. SAS/STAT user’s guide, version 9.1. SAS Institute, Cary, NC. 128 2007 Potato Research Report Michigan Potato Industry Commission George W. Bird, Professor Department of Entomology Michigan State University to Soil Quality Restoration (BOKS Trial) In 2003, a soil quality restoration research site was established at the Montcalm Potato Research Farm. This was a cooperative projective with George Bird, Sieglinde Snapp, Willie Kirk and Mark Otto serving as co-principal investigators. The trial consisted of four soil management systems: 1) Fumigated control (wheat/rye/potato), 2) Biofumigant (mustard and rye/sudax/mustard & rye/potato 3) Wheat and mustard (wheat/mustard and rye/potato), and 4) Legume (hairy vetch and rye/soybean green manure/vetch and rye/potato (Table 1) . Each management system was replicated four times at the Montcalm Potato Research Farm. Table 1. 2004-2007 BOKS Trial management systems. Treatment 2007 2005 2006 2004 Wheat/Rye Mus/Rye/Sudax/Rye Wheat/Mustard/Rye Soybean/Vetch/Rye 1. 2. 3. 4. Vapam/Potato Wheat/Rye Vapam/Potato Potato Potato Potato Mus/Rye/Sudax/Rye Wheat/Mustard/Rye Soybean/Vetch/Rye Potato Potato Potato Based on nematode community structure analysis (Appendix A), the overall soil quality was poor at the end of the 2004 growing season (Table 2). There were, however, significant differences among the four management systems. The fumigated system had the highest relative density of fungivores. The biofumigation system had the highest population density of bacterivores and the highest overall absolute density. The legume system had highest relative and absolute population densities of herbivores, leading to a significant negative impact on tuber yield. 129 0.91 0.04 0.02 0.02 0.00 0.79 0.04 0.10 0.06 0.00 0.68 0.08 0.21 0.04 0.00 59 633 290 391 Fumigation Biofumigation Wheat/Mustard Legume Table 2. Nematode community structure [relative (%) and absolute population densities per (100 cm3 soil)] at end of the first year of the soil quality restoration trial (BOKS Trial) Montcalm Potato Research Farm Soil Quality Restoration Trial. _______________________________________________________________________ Nematode Guild (P) ________________________________________________________________________ Bacterivores (0.001) 0.75 Fungivores (0.252) 0.15 Herbivores (0.088) 0.03 Omnivores (0.300) 0.07 Carnivores (1.000) 0.00 Absolute Density ________________________________________________________________________ Tuber yields in 2005 were highly correlated with cover-crop and early-season population densities of root-lesion nematodes (Fig. 1.). The highest nematode population densities (200/g root tissue) and lowest tuber yields (<350 cwt/acre) were associated with the legume system (Fig. 2) . The lowest nematode population densities (very close to 0) and the highest potato tuber yields (438 cwt/acre) were associated with the fumigant system. Yields from the fumigated and bio-fumigated plots, however, were not significantly different from each other. In the 2005 Research Report, it was reported that the bio-fumigation system looks very promising and will be improved on during the second two-year cycle of the project. The post-fumigation recovery of beneficial nematodes (from a potato production point-of- view) appears to be more rapid with the bio-fumigation than following chemical fumigation with metham. The highest yielding plot (>460 cwt/are) was a bio-fumigation plot (Figure 2). Yields associated with all of the fumigation plots were nearly identical. The low yields in three of the four legume plots, one wheat/mustard plot and one failed bio-fumigation plot were all associated with early-season cover-crop root-lesion nematode population densities greater than 50/1.0 gram of root tissue. Although the bio- fumigation associated with this trial looks very promising, the two-year nature of the trial may be inadequate. It is estimated that at least three cycles of the soil enhancement systems will be required to see a significant improvement in overall soil quality. By the end of the 2006 growing season, nematode population densities associated with the Management Systems 2-4 had increased, compared to the 2004 data (Table 3) and those associated with the fumigation treatment were significantly less (P = 0.05) than those associated with the wheat-mustard, biofumigant and legume systems. 130 1. 2. 3. 4. Total 755 a 2019 b 2036 b 1869 b 668 a 1919 b 1930 b 1729 b 25 a 45 a 45 a 53 a 38 a 10 a 35 a 60 a Herbivores 30 a 40 a 40 a 25 a Table 3. End of 2006 growing season nematode community structure (absolute population densities) associated with the four BOKS Trial management systems. Treatment Bacterivores Fungivores Omnivores Figure 1. 2005 potato tuber yields (cwt/A) and root-lesion nematode (Pratylenchus penetrans) population densities per 1.0 g cover-crop root tissue at the beginning of the growing season in the soil restoration (BOKS) trial at the Montcalm Potato Research Farm. t o o r g 0 . 1 / s n a r t e n e p s u h c n e l y t a r P i P 5 0 0 2 250 200 150 100 50 0 -50 BOKS Trial, 2005 Fumigation Biofumigation Wheat/Mustard Legume Potato Management System PP Yield 500 450 400 350 300 250 200 150 100 50 0 ) A / t w c ( d l e i Y 131 The 2007 tuber yields (total, As and jumbos) associated with the soil fumigation management system were significantly greater (P = 0.05) than those associated with the wheat-mustard, biofumigation or legume systems (Table 4). There were no significant difference among the systems for the B grade tubers. Figure 2. Relationships among 2005 potato tuber yields, early-season root-lesion nematode (Pratylenchus penetrans) population densities and management systems. BOKS Trial, 2005 500 450 Biofumigation (highest Yeild) Fumigation (All the fumigants, Yields range from 429 to 432 and Pp from 0 to 4) ) Wheat/Mustard A / t w c ( s d l e i Y r e b u T Legume 400 Biofumigation 350 Biofumigation Biofumigation Wheat/Mustard 300 250 0 Wheat/Mustard Legume Wheat/Mustard Legume Legume 50 100 150 200 250 300 Early-Season Pratylenchus penetrans per 1.0 gm root tissue Table 4. 2007 potato tuber yields associated with the BOKS soil management system trial. Treatment Yield (cwt/A) Jumbo Grade B Grade 1. 2. 3. 4. 327 a 231 b 229 b 242 b A Grade 285 a 208 b 210 b 216 b 94 a 19 b 15 b 9 b 9 a 9 a 11 a 11 a 132 1. 2. 3. 4. 3 a 20 b 11 b 56 c 2.6 a 3.5 a 3.6 a 3.6 a The 2007 mid-season root-lesion nematode population density associated with the fumigated system was significantly (P = 0.05) greater than the population densities associated with the biofumigation, wheat-mustard or legume systems (Table 5). In general, scab associated with the fumigated system was lower than that associated with the other management systems (Table 5). Table 5. 2007 mid-season root-lesion nematode and scab associated with four potato management systems. Treatment Root-lesion Nematodes (08) Scab Index (0-5) Cover-Crop/Root-Lesion Nematode Host Assessment Cover crops can be used in agricultural for many different production system objectives. These include: During the past five years it has been learned that selecting the appropriate variety of the cover crop is essential. For example, Michigan sugar beet growers use Adagio or Colonel oil seed radish as a trap crop for management of the sugar beet cyst nematode. These varieties were developed specifically for this purpose. Both are good hosts for the penetrans root-lesion nematode and are not appropriate for use by Michigan potato growers for management of potato early-die. - Soil Quality Enhancement (Soil Organic Matter Quality and Quantity) - Soil Quality Maintenance (SOM Quality and Quantitly) - Erosion Management - Crop Nutrition (Nitrogen Fixation, Green Manure) - Soil Water Enhancement (Decrease in Irrigation Requirements) - Weed Management (Numerous Mechanisms) - Non-Hosts (Lowering Plant Pathogen Populations) - Trap Crops (Trapping and Killing Pathogens) - Bio-Fumigation (Lowering Plant Pathogen Populations) - Livestock Grazing - Hay Crop - Silage Crop - Seed Crop 133 Because of the diversity of the host range of the penetrans root-lesion nematode, identification of cover crops that are non-hosts for this nematode has been difficult. In 2005, the University of Wisconsin reported that Pearl Millet may have this property. This hypothesis was tested in 2006 at the Montcalm Potato Research Farm in a twelve cover crop trial, with each variety being replicated six times. In this trial, Pearl Millet 444 and Pearl Millet Millex 32 were the poorest hosts for the root-lesion nematode and should have excellent potential for use in Michigan potato production systems (Table 6). This site was planted to corn in 2007. The best early-season corn growth was associated with the pearl millet cover crops (Table 6). Table 6. 2006 root-lesion nematode reproduction and 2007 corn growth associated with 12 cover crops at the Montcalm Potato Research Farm. Cover crop 2006 Root –lesion 2007 Corn Growth Index (1-4) Millet pearl 444 3 3.5 Millet Pearl Millex 32 5 4.0 Millet Pearl Leafy 23 14 4.0 White Mustard 10 2.0 Mustard Mix 34 3.0 Yellow Mustard 37 1.5 Mustard Bio-Fumigation Blend 26 1.8 Oil Seed Radish, Common 21 2.8 Oil Seed Radish, Colonel 53 2.3 Rape 60 2.0 Sudax 16 3.3 Wheeler Rye 155 2.5 Summary The BOKS Trial was an excellent research investment. It was shown that it takes more than two years to significantly enhance the overall quality of soil It was also demonstrated that proper cover crop selection and management is imperative to obtain the desired system objectives from these plants. Much has been learned about soil quality and associated management systems during the past five years. Much, however, remains to be learned. The BOKS Trial has set the environment for the next stage of development associated with the long-term development and maintenance of soil, an essential natural resource. It also provides a foundation for the future work of the Michigan Potato Industry and its future work with Dr. Grandy, the new Assistabnt Professor of Soil Biology at Michigan State University. 134 Appendix A. Today, modern science estimates that four out of every five animals currently alive on our planet are nematodes. Their feeding behaviors are highly diverse as indicated in the following illustration (modified from the 2005 and 2006 Annual Reports). Feeding Behaviors of Nematodes in Soil Food Webs Bacterial Feeders • N.A. Cobb (1915) … if all the matter in the universe except the Plant Feeders nematodes was swept away, our world would still be dimly recognizable – we would find mountaintops, valleys, rivers, lakes and oceans recognizable – by a thin film of nematodes. Fungal Feeders Algal Feeders Omnivores Carnivores The bacterial and fungal feeding nematodes are of major significance in agriculture because of their role in making soil nutrients available for plant growth and development. As illustrated in the following figure, nitrogen mineralization takes place in the immediate root environment (rhizosphere) where it is taken up and used by the plant before having the opportunity to be transformed and transported to other parts of the environment, such as groundwater or the atmosphere. 135 Appendix A (continued) Energy CO2 Function of bacterial feeding nematodes in crop systems Shoot System Rhizosphere + NH4 ─ NO3 Sugar Exudate Nematode C:N 10:1 Bacteria C:N 5:1 Root System H2O Nutrients Bird, 2002 o Recent research shows that nematode community structure varies greatly among different types of Michigan ecosystems. In 2006, a Nematode Community Structure Standard was developed and is being used for assessment of soil quality. In the following figure, the numbers in the bottom row represent the total nematode population density present (number of nematode) present in a cup of soil, for each of four different ecosystems (wood lot, old field succession, conventional agriculture, organic agriculture). The other numbers in each column represent the % of the population in each of the six different feeding behavior groups for each specific ecosystem. More than 50% of the nematodes associated with the conventional corn-soybean system were plant root feeders and very few bacterial or fungal feeding nematodes detected. This is not a desirable situation. 136 Appendix A (continued) Nematode Community Structure Michigan Relative Density Standard (G.W.Bird, based on the Works of J. Smith and M. Berney) Feeding Behavior Woodlot Old Field Succession Bacterivore Fungivore Herbivore Omnivore Carnivore Algavore Absolute Density 51 18 28 3 1 NA 500 83 7 7 2 1 0.03 1700 High Soil Quality 73 26 0.6 0.2 0.003 NA 3500 Poor Soil Quality 28 14 57 0.2 0.05 NA 200 137 Funding: MPIC and NPC Evaluation and comparison of biofungicides and fungicides for the control of post harvest potato tuber diseases. Kirk, W. W., and Wharton, P. S., Department of Plant Pathology, Michigan State University, East Lansing, MI 48824. Summary Potatoes are susceptible to a variety of storage pathogens, including late blight (Phytophthora infestans), Fusarium dry rot (Fusarium sambucinum), Pythium leak (Pythium ultimum), tuber soft rot (Erwinia spp.), and silver scurf (Helminthosporium solani). Current recommendations for potato storage diseases include sanitation and exclusion as the primary controls for these pathogens in storage facilities. No fungicides are registered for direct application to tubers for control of these important pathogens and few compounds are available for potato tuber treatment in storage, including chlorine- based disinfectants such as, sodium hypochlorite, calcium hypochlorite and chlorine dioxide. In recent years several new biofungicides based on the biocontrol bacteria Bacillus subtilis Serenade) and B. pumilis (Sonata) have been registered or are awaiting EPA approval for use on potato, and have shown promise in the control of seed and soil borne diseases such as late blight, black scurf and pink rot. None of these products has been evaluated for the control of these pathogens under post-harvest potato tuber storage conditions. Thus, studies were initiated to evaluate the efficacy of these biofungicides for the control of potato storage pathogens under post-harvest conditions. For a comparison, several commercial storage products Phostrol (sodium, potassium and ammonium phosphates), and Oxidate (hydrogen dioxide) and experimental treatment Quadris (azoxystrobin) were evaluated for their effectiveness under storage conditions. Preliminary results show that in general conventional fungicide Quadris provided the most effective disease control. The biofungicides provided more limited control. However, in all cases results for the biofungicides were not significantly different from those for Quadris. In the case of Pythium, the biofungicides were as effective in controlling disease as Quadris and results were not significantly different from the non-inoculated control. Introduction Potatoes are susceptible to a variety of storage pathogens, including late blight (Phytophthora infestans), Fusarium dry rot (Fusarium sambucinum), Pythium leak (Pythium ultimum), pink rot (Phytophthora erythroseptica) and tuber soft rot (Erwinia spp). These pathogens are of major concern to potato producers due to the great losses they cause in stored potatoes. Current recommendations for potato storage diseases include sanitation and exclusion as the primary controls for these pathogens. No fungicides are registered for direct application to tubers for control of these pathogens and few compounds are available for potato tuber treatment in storage. In recent years, several new biofungicides based on the biocontrol bacteria Bacillus subtilis (Serenade) and B. pumilis (Sonata) have been registered or are awaiting EPA approval for use on potato. These have shown promise in the control of seed and soil borne diseases such as late blight and pink rot. Neither of these products has been evaluated for the control of potato storage pathogens under post-harvest conditions. Thus, studies were initiated to evaluate the efficacy of these biofungicides under post-harvest storage conditions. For a comparison, several commercial storage products Oxidate (hydrogen dioxide), and Phostrol (sodium, potassium and ammonium phosphates) and experimental treatment Quadris (azoxystrobin) were evaluated for their effectiveness under storage conditions. Materials and Methods Experiments were carried out in November 2006 with potato cultivar “FL1879”. Potatoes free from visible diseases were selected for the trials from tubers harvested in October 2006. Tubers were 138 Funding: MPIC and NPC prepared for inoculation by grazing with a single light stroke with a wire brush, sufficient to abrade the skin of the tubers to a depth of 0.01 mm. Solutions (1 x 103/ml ) of sporangia/zoosporangia of P. infestans (late blight), oospores/sporangia of P. erythroseptica (pink rot), oospores of P. ultimum (Pythium leak), macroconidia of F. sambucinum (dry rot) and bacterial cells of E. carotovora (soft rot) were prepared from cultures of the pathogens previously isolated from potato tubers in Michigan. All pathogens were grown on PDA for 10 days prior to preparation of inoculum solutions. Two non- treated controls, either inoculated with one of the pathogens or non-inoculated were included in the trial. Damaged tubers, (10/replicate/treatment; total 40 tubers/treatment) were sprayed with 10 ml of pathogen suspension, for a final dosage of about 0.25 ml per tuber. Tubers were stored for 24 h after inoculation at 20°C before treatment. Fungicides were applied as liquid treatments in a water suspension with a single R&D XR11003VS spray nozzle at a rate of 1L/ton at 50 psi onto the tuber surfaces, with an entire seed surface being coated in the seed treater. After inoculation, tubers were incubated in the dark in plastic boxes at 12°C for 60 days. Tubers were cut open and the number of tubers with symptoms or signs of the individual pathogens were counted to determine incidence of disease. Disease severity was assessed using a disease severity index. Disease severity classes were determined as class 0 = 0%; 1 = 1 - 10%; 2 = 11 - 20%; 3 = 21 - 50; 4 > 51 – 100% internal area of tuber tissue with disease. The disease severity index was then calculated as the number in each class multiplied by the class number and summed. The sum was then multiplied by a constant to express severity on a 0 – 100 scale. Data were analyzed using analysis of variance and the Tukey’s LSD test in JMP (SAS Institute, NC). Results and Conclusions In the late blight studies (Table 1) all of the treatments had a significantly lower incidence of disease and mean disease severity index than the inoculated/not-treated check. There was no significant difference among any of the treatments and the untreated/not-inoculated check (Table 1). No disease was observed in any of the not-inoculated treatments. Overall, disease incidence and severity was low even in the inoculated check (Table 1). In the Pythium leak experiment (Table 2), all of the not- inoculated treatments were not significantly different from then inoculated check. Inoculated treatments treated with Oxidate or Quadris were significantly different from the inoculated/not-treated check and not significantly different from the untreated check. Phostrol, Serenade (high and low) and Sonata all had disease incidences and a mean disease index that was not significantly different from the inoculated/not-treated check, with the highest disease incidence occurring in the low rate Serenade treatment. Quadris provided the best disease control. In the Fusarium dry rot experiments (Table 3), all of the treatments had a significantly lower disease index than the inoculated check and were not significantly different to the untreated check. However, mean disease incidence in the inoculated biofungicide treatments Sonata, and Serenade (high rate), were not significantly different to the inoculated/not-treated check. Phostrol and Oxidate provided the best disease control followed closely by Quadris. In the pink rot experiments (Table 4), no disease was found in any of the not-inoculated treatments and the untreated/not-inoculated check. Disease incidence and severity in the inoculated/not-treated check was relatively low. The inoculated Sonata and Serenade (low) treatments were not significantly different from the inoculated/not-treated check. Disease incidence in all other inoculated treatments was close to zero and not significantly different from the untreated/not- inoculated check. Overall in this study, Serenade and Sonata provided limited control of potato storage diseases, while treatment with Oxidate, Phostrol and Quadris provided effective disease control. 139 Funding: MPIC and NPC Table 1. Percentage of tubers in each disease severity class, the mean potato late blight severity indices and disease incidences 120 days after treatment with fungicides/biofungicides. Percentage of tubers in each disease severity class3 Class 5 Class 4 Inoculation2 Class 0 Class 1 Class 2 Class 3 Treatment (rate/cwt)1 Untreated check Inoculated check Sonata (0.32) Serenade High (0.32) Serenade Low (0.16) Phostrol (2.56) Oxidate (0.125) Quadris (0.125) 1 The rate of product in fl. oz. (oz. for Quadris) per hundredweight seed tubers applied in mixture with water at 2 L/ton. 2 “+” tubers were inoculated; “–” tubers were not inoculated immediately after wounding. 3 Severity classes were determined as class 0 = 0%; 1 = 1 - 10%; 2 = 11 - 20%; 3 = 21 - 50; 4 > 51 – 100% internal area of tuber tissue with 100.0 77.5 100.0 93.8 100.0 95.0 100.0 97.5 100.0 96.3 100.0 97.5 100.0 100.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 5.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 8.8 0.0 1.3 0.0 2.5 0.0 2.5 0.0 1.3 0.0 2.5 0.0 0.0 0.0 3.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 5.0 0.0 5.0 0.0 2.5 0.0 0.0 0.0 2.5 0.0 0.0 0.0 0.0 – + – + – + – + – + – + – + Mean Severity Index4 0.0 c5 15.3 a 0.0 c 5.8 b 0.0 c 4.0 bc 0.0 c 1.5 bc 0.0 c 3.3 bc 0.0 c 1.5 bc 0.0 c 0.0 c Mean disease incidence 0.0 b 22.5 a 0.0 b 6.3 b 0.0 b 5.0 b 0.0 b 2.5 b 0.0 b 3.8 b 0.0 b 2.5 b 0.0 b 0.0 b 4 The severity index is the number in each class multiplied by the class number and summed. The sum is then multiplied by a constant to disease. express severity on a 0 – 100 scale. 5 Mean values of diseased tubers within a column followed by the same letter are not significantly different at p = 0.05 (Tukey test). Table 2. Percentage of tubers in each disease severity class, the mean Pythium leak severity indices and disease incidences 120 days after treatment with fungicides/biofungicides. Percentage of tubers in each disease severity class3 Class 5 Class 4 Inoculation2 Class 0 Class 1 Class 2 Class 3 Treatment (rate/cwt)1 Untreated check Inoculated check Sonata (0.32) Serenade High (0.32) Serenade Low (0.16) Phostrol (2.56) Oxidate (0.125) Quadris (0.125) 1 The rate of product in fl. oz. (oz. for Quadris) per hundredweight seed tubers applied in mixture with water at 2 L/ton. 2 “+” tubers were inoculated; “–” tubers were not inoculated immediately after wounding. 3 Severity classes were determined as class 0 = 0%; 1 = 1 - 10%; 2 = 11 - 20%; 3 = 21 - 50; 4 > 51 – 100% internal area of tuber tissue with 100.0 65.0 100.0 63.8 100.0 72.5 98.8 60.0 100.0 78.8 100.0 86.3 100.0 95.0 0.0 17.5 0.0 22.5 0.0 22.5 1.3 27.5 0.0 13.8 0.0 7.5 0.0 5.0 0.0 11.3 0.0 13.8 0.0 5.0 0.0 8.8 0.0 6.3 0.0 3.8 0.0 0.0 0.0 2.5 0.0 0.0 0.0 0.0 0.0 3.8 0.0 1.3 0.0 1.3 0.0 0.0 0.0 2.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.3 0.0 0.0 – + – + – + – + – + – + – + Mean Severity Index4 0.0 d5 29.3 ab 0.0 d 33.5 a 0.0 d 26.5 ab 1.3 d 36.8 a 0.0 d 19.5 bc 0.0 d 11.5 cd 0.0 d 5.0 d Mean disease incidence 0.0 e 35.0 a 0.0 e 36.3 a 0.0 e 27.5 ab 1.3 de 40.0 a 0.0 e 21.3 bc 0.0 e 13.8 cd 0.0 e 5.0 de 4 The severity index is the number in each class multiplied by the class number and summed. The sum is then multiplied by a constant to express severity on a 0 – 100 scale. 5 Mean values of diseased tubers within a column followed by the same letter are not significantly different at p = 0.05 (Tukey test). disease. 140 Table 3. Percentage of tubers in each disease severity class, the mean Fusarium dry rot severity indices and disease incidences 120 days after treatment with fungicides/biofungicides. Funding: MPIC and NPC Percentage of tubers in each disease severity class3 Inoculation2 Class 0 Class 1 Class 2 Class 3 Class 4 Class 5 Treatment (rate/cwt)1 Untreated check Inoculated check Sonata (0.32) Serenade High (0.32) Serenade Low (0.16) Phostrol (2.56) Oxidate (0.125) Quadris (0.125) – + – + – + – + – + – + – + 91.3 43.8 81.3 65.0 80.0 67.5 88.8 68.8 96.3 90.0 95.0 87.5 97.5 78.8 0.0 6.3 7.5 10.0 11.3 8.8 8.8 8.8 2.5 1.3 1.3 1.3 2.5 0.0 3.8 27.5 10.0 25.0 8.8 16.3 2.5 15.0 1.3 6.3 3.8 10.0 0.0 17.5 0.0 0.0 1.3 0.0 0.0 5.0 0.0 6.3 0.0 2.5 0.0 1.3 0.0 3.8 2.5 17.5 0.0 0.0 0.0 2.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.5 5.0 0.0 0.0 0.0 0.0 0.0 1.3 0.0 0.0 0.0 0.0 0.0 0.0 Mean Severity Index4 6.0 bcd5 31.3 a 6.3 bcd 12.0 bc 5.8 bcd 13.3 b 2.8 cd 12.8 b 1.0 d 4.3 bcd 1.8 d 5.0 bcd 0.5 d 9.3 bcd Mean disease incidence 8.8 cd 56.3 a 18.8 bcd 35.0 ab 20.0 bcd 32.5 abc 11.3 bcd 31.3 bc 3.8 d 10.0 cd 5.0 d 12.5 bcd 2.5 d 21.3 bcd 1 The rate of product in fl. oz. (oz. for Quadris) per hundredweight seed tubers applied in mixture with water at 2 L/ton. 2 “+” tubers were inoculated; “–” tubers were not inoculated immediately after wounding. 3 Severity classes were determined as class 0 = 0%; 1 = 1 - 10%; 2 = 11 - 20%; 3 = 21 - 50; 4 > 51 – 100% internal area of tuber tissue with 4 The severity index is the number in each class multiplied by the class number and summed. The sum is then multiplied by a constant to disease. express severity on a 0 – 100 scale. 5 Mean values of diseased tubers within a column followed by the same letter are not significantly different at p = 0.05 (Tukey test). Table 4. Percentage of tubers in each disease severity class, the mean pink rot severity indices and disease incidences 120 days after treatment with fungicides/biofungicides. Percentage of tubers in each disease severity class3 Treatment (rate/cwt)1 Untreated check Inoculated check Sonata (0.32) Serenade High (0.32) Serenade Low (0.16) Phostrol (2.56) Oxidate (0.125) Quadris (0.125) Inoculation2 Class 0 Class 1 Class 2 Class 3 Class 4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 100.0 81.3 100.0 87.5 100.0 90.0 100.0 80.0 100.0 96.3 100.0 96.3 100.0 98.8 0.0 13.8 0.0 10.0 0.0 6.3 0.0 12.5 0.0 3.8 0.0 3.8 0.0 1.3 0.0 3.8 0.0 2.5 0.0 3.8 0.0 3.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.3 0.0 0.0 0.0 0.0 0.0 3.8 0.0 0.0 0.0 0.0 0.0 0.0 – + – + – + – + – + – + – + Class 5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Mean Severity Index4 0.0 c 8.0 a 0.0 c 5.5 a 0.0 c 4.8 ab 0.0 c 8.0 a 0.0 c 1.5 bc 0.0 c 1.5 bc 0.0 c 0.5 c Mean disease incidence 0.0 d 18.8 a 0.0 d 12.5 ab 0.0 d 10.0 bc 0.0 d 20.0 a 0.0 d 3.8 cd 0.0 d 3.8 cd 0.0 d 1.3 d 1 The rate of product in fl. oz. (oz. for Quadris) per hundredweight seed tubers applied in mixture with water at 2 L/ton. 2 “+” tubers were inoculated; “–” tubers were not inoculated immediately after wounding. 3 Severity classes were determined as class 0 = 0%; 1 = 1 - 10%; 2 = 11 - 20%; 3 = 21 - 50; 4 > 51 – 100% internal area of tuber tissue with disease. express severity on a 0 – 100 scale. 4 The severity index is the number in each class multiplied by the class number and summed. The sum is then multiplied by a constant to 5 Mean values of diseased tubers within a column followed by the same letter are not significantly different at p = 0.05 (Tukey test). 141 Funding: MPIC Summary Report for the 2006-2007 Dr. B. F. (Burt) Cargill Potato Demonstration Storage Brian Sackett, Chris Long, Dick Crawford, Todd Forbush (Techmark, Inc.), Steve Crooks, Dennis Iott, Keith Tinsey, Tim Young, Jason Walther, Troy Sackett, Randy Styma and Ben Kudwa Introduction This is a summary report of the 2006-2007 Dr. B.F. (Burt) Cargill Potato Demonstration Storage Annual Report Volume 6. This report is designed to provide a short summary of the 2006-2007 storage committee activities. To obtain a copy of the full 2006-2007 Demonstration Storage Report please contact the Michigan Potato Industry Commission office (517-669-8377) or Chris Long at Michigan State University (517-355-0271 ext.#193). The full report will be provided to you free of charge. Goals and Objectives The 2006 growing season resulted in above average specific gravity with strong overall yields. The early part of the growing season was cool and wet with a warm and humid summer. The harvest season was generally cold and wet causing severe breakdown in storage resulting in above average losses. The goal of the MPIC Storage and Handling Committee for the 2006-2007 bulk bin storage season was to develop more in-depth storage profiles on three commercially available varieties. They were MegaChip, Monticello and Beacon Chipper. MegaChip has shown susceptibility to above average levels of external defects. These defects result in detrimental sugar accumulation which intern results in defects in the finished chips. Because of this, our objectives were to manage the accumulation of internal sugars around these external defects through the utilization of pile temperature and fresh air volume. Our second variety of interest was Monticello. The objective for this variety during this storage season was to precondition one bulk bin and recondition the other bin 142 prior to shipping in late May or early June. Two bulk bins of Beacon Chipper were stored in 2006. One bin from Sandyland Farms and the other from Sackett Acres. The variety has performed well in the storage facility for three consecutive years. The storage committee was interested in comparing grower practices and observing if grower specific practices appeared to affect the storage quality of this variety. All bins were treated with CIPC on October 24th and December 20th, 2006. Results for the 500 cwt. Bulk Bins: MegaChip Bulk Bin 2. These potatoes were planted on April 22, 2006 and harvested on September 18, 2006 at 67.0 ºF pulp temperature. The potatoes were grown at Crooks Farms and were received with an 84% bruise free rating. The sucrose rating rose from 0.529 at harvest to 0.694 in early November, at which point a steady decline was recorded until the first of January, 2007. The sucrose rating rose from 0.421 in January to 0.651 in mid February, at which point the potatoes were processed at Utz Quality Foods in Hanover, PA. From October 2006 until shipment in 2007 the percent glucose remained steady at 0.002. The variety averaged over 10 percent total chip defects during storage evaluation. The load, when processed at Utz, scored 1 percent external and 3 percent internal defects in the finished product with an AGTRON score of 61.6. The storage temperature of this bin in late September was 58.2 ºF and trended downward to 54.8 ºF in mid February when the bin was sold. MegaChip has many positive agronomic traits; yield, scab tolerance, vine vigor and high specific gravity. Given this varieties slower respiration rate and high specific gravity, it was a challenge to precondition and store with confidence. There was a great concern with the amount of internal and external defects present as to whether this bin would process acceptably. The bin did process acceptably, but much reservation was had about the storability of this variety. We will continue to attempt to expand our confidence in this variety in the future. Monticello Bulk Bin 3. The results of this preconditioning and reconditioning study were mixed. The potatoes in bulk bins #3 and #4 were from Sackett Potatoes and were planted May 3, 2006. They were harvested October 6th and loaded into the storage bins the following day at 55 ºF. Bins 3 and 4 were 79 and 74 percent black spot bruise free, respectively. The Monticello in bulk bin 3 had a sucrose rating of 0.705 in late October, 143 2006 which declined steadily to 0.462 in mid February, 2007. The percent glucose was high during the first three months in storage and then declined to 0.003 percent glucose on the 12th of February. The pile temperature was kept warm at 55 ºF to precondition the potatoes, but in doing so, multiple spots of potato soft rot advanced to the point that the bin needed to be moved before the bin was lost. Total chip defects declined from over 30 percent in late October, 2006 to 6.1 percent on the day of shipping in February, 2007. The variety was able to be preconditioned, but due to carryover of field vine rot and the tubers being stored at warmer temperatures, the soft rot in the bin resulted in premature marketing. This bin was processed at Utz on February 14, 2007 with a total of 5 percent defects and an AGTRON score of 63.5. Monticello Bulk Bin 4. The potatoes in this bin were identical to those in bin #3. Our desire was to cool the tubers as soon as possible to extend storage life and then recondition in the Spring prior to shipping, similar to commercial practices for the Snowden variety. After two months in storage at 55 ºF this variety was cooled to 50 ºF over a four week period. The ending storage temperature was 50.0 ºF on the 26th of February when this bin was shipped to Utz Quality Foods. The sucrose rating and percent glucose were sporadic through the cooling period and appeared to be unstable most of the season. At the date of shipping, the sucrose rating and percent glucose were 0.396 and 0.002 respectively, which appeared to be more representative of a typical storage variety at this point in the season. Total chip defect levels were 5 percent on the 26th of February, 2007. The variety appeared to cleanup just prior to shipping. The Monticello’s in this bin began exhibiting areas of wet break down and were sold prematurely also. They were processed at Utz on February 28th with 8 percent total defects and an AGTRON score of 64.2. Beacon Chipper (Sandyland) Bulk Bin 5. The Beacon Chipper’s that were in bulk bin #5 were grown by Sandyland Farms, LLC. They were planted April 28, 2006, harvested September 17, 2006 and loaded into storage the following day at 61.0 ºF. These potatoes were 86 percent black spot bruise free at the time of bin loading. From past storage profiling we knew that Beacon Chipper would maintain good storage quality until late February. The sucrose rating at harvest was 0.731 with a 0.002 percent glucose value. The sucrose rating declined to a low of 0.381 in early December of 2007 with a 0.002 144 percent glucose value. The pile temperature was cooled from 58.0 ºF in late September to 50 ºF by early January, 2007. The pile temperature remained at 50.0 ºF until shipping on February 14th, 2007. This bin averaged around 10 percent chip defects during the storage season. The bin was processed at Herr’s Foods, Knottingham, PA on February 15, 2007 with a total of 17 percent chip defects recorded at the plant. Most of the defects were a result of pressure bruise and internal shading. The bin recorded a 62.1 AGTRON score with a 1.074 specific gravity and a 2.0 SFA score. Overall, the bin stored and processed well. This variety appears to works well in the late “out of the field” or early storage market window. Beacon Chipper (Sackett Acres) Bulk Bin 6. The potatoes in bin 6 were grown at Sackett Acres, Inc. They were planted April 27th, 2006, harvested September 21st, 2006 and loaded into storage the following day at 61.0 ºF. The potatoes were received with an 88 percent black spot bruise free rating. The potatoes were received with a moderate amount of surface scab. The sucrose rating at harvest was 0.882 with a 0.002 percent glucose value. The sucrose level declined to 0.554 in mid November with the percent glucose value remaining flat at 0.002. The pile temperature at this time was 53.9 ºF. As the pile temperature was cooled to 49.0 ºF in mid January, sucrose levels rose to a high of 0.654. After five weeks at 49.0 ºF the sucrose rating declined to 0.443 with a percent glucose value of 0.001 at the time of shipping. Total chip defect at the time of shipping was 0.0 from our storage testing. Herr’s reported a 60.9 AGTRON score and a 2.0 SFA score with a 1.074 specific gravity. Herr’s defects were much higher than reported at the storage due to the amount of surface scab observed at the plant. Overall, bulk bin 5 and 6 processed similarly even though they were grown under different production practices. Promising Varieties In the Box Bin Trial: Varieties that looked promising in the Box Bin trial (Bin 1) in 2006 for long term storage were Monticello, CO95051-7W, MSJ126-9Y, MSJ147-1 and MSJ316-A. These varieties will be considered for larger scale evaluations in the 2007-2008 storage season. 145