1984 MONTCALM FARM RESEARCH REPORT MICHIGAN STATE UNIVERSITY AGRICULTURAL EXPERIMENT STATION IN COOPERATION WITH THE MICHIGAN POTATO INDUSTRY COMMISSION THE MICHIGAN POTATO INDUSTRY COMMISSION April 5, 1985 TO All Michigan Potato Growers and Shippers: This Potato Research Report is the result of the research that was carried on by Michigan State University at the Montcalm Research Farm, Entrican, Michigan as well as other potato research projects conducted during 1984. The continued research on Michigan potatoes is a direct result of the monies that growers and shippers have paid into the Michigan Potato Industry Commission. Only through this support can the potato industry in Michigan continue with similar research in the future. Thank you. Sincerely, Roy H. Kaschyk Executive Director RHK:cc THE MICHIGAN POTATO INDUSTRY COMMISSION • 241 E. SAGINAW, STE. 403 • EAST LANSING, Ml 48823 • (517)373-3783 ACKNOWLEDGEMENTS Research personnel working at the MSU Montcalm Branch Experiment Station have received considerable assistance in various ways. The Michigan Potato Industry Commission has granted substantial research dollars to support many of the projects included in this report. A special thanks is given to the MPIC, private companies, and government agencies who have made this research possible. Many contributions in the way of fertilizers, chemicals, seed, equipment, technical assistance, personal services, and monetary grants were also received and are hereby gratefully acknowledged. Contributions of Russet Burbank seed and the processing of samples for bruise determinations were provided by Ore-Ida Foods, Inc. and we gratefully acknowledge their continued support of MSU potato research. Recognition is also given to Mr. Theron Comden for his dedicated cooperation and assistance in many of the day-to-day operations. Acknowledgement is also made to Dick Kitchen for his fine leadership in coordinating the production management needs of the Station throughout the planting, growing and harvest season. TABLE OF CONTENTS Page INTRODUCTION, WEATHER, AND GENERAL MANAGEMENT ..................................................... 1 1984 POTATO VARIETY INTRODUCTIONS AND EVALUATIONS R.W. Chase, R.B. Kitchen, and R. Hammerschmidt................................................ 4 1984 POTATO VARIETY EVALUATIONS - DELTA COUNTY, MICHIGAN R.H. Leep, J.R. Lempke, D.L. Pellegrini, R.W. Chase. and R.W. Hammerschmidt................................... 20 CONTROL OF SCAB AND RHIZOCTONIA DISEASES R. Hammerschmidt.......................................................................................................................22 BIOLOGY AND CONTROL STRATEGIES FOR INSECT PESTS OF POTATOES E. Grafius, E. Morrow and A. May....................................................................................27 1984 NEMATOLOGY RESEARCH G. W. Bird........................................................................................................................................ 40 THE INFLUENCE OF FOLIAR FERTILIZERS AND A SOIL FUMIGANT ON PLANT NUTRITION, YIELD AND TUBER QUALITY OF POTATOES M.L. Vitosh, G.W. Bird, R. Leep, R. Hammerschmidt, R.W. Chase and E. Grafius...................................................................................................... 48 EFFECT OF FIELD PRODUCTION TREATMENTS, PRESTORAGE HANDLING, CHEMICAL AND MECHANICAL TREATMENTS AND STORAGE ENVIRONMENTS OF POTATOES OUT OF EXTENDED STORAGE B.F. Cargill, R.L. Ledebuhr, K.C. Price, T.D. Forbush and H. S. Potter.....................................................................................................................................68 EFFECT OF FIELD PRODUCTION TREATMENTS ON THE MARKET QUALITY OF POTATOES OUT OF EXTENDED STORAGE (1983 MSU INTEGRATED PROJECT - STORAGE PHASE) ..................................................................................................... 69 QUALITY/MARKETABILITY OF POTATOES OUT OF EXTENDED STORAGE DUE TO PRESTORAGE HANDLING, CHEMICAL AND MECHANICAL TREATMENTS AND STORAGE ENVIRONMENTS .......................................................................... 75 INFLUENCE OF LOW VOLUME PRESTORAGE CHEMICAL TREATMENT ON THE MARKET QUALITY OF COMMERCIALLY PRODUCED POTATOES ................................... 80 CORN HYBRIDS, PLANT POPULATIONS AND IRRIGATION E.C. Rossman and Keith Dysinger......................................................................................... 82 MONTCALM FARM, 1984 - COLORED BEAN BREEDING AND TESTING M.W. Adams, J.D. Kelly, and J. Taylor......................................................... 89 1984 POTATO RESEARCH REPORT R.W. Chase, Coordinator Department of Crop and Soil Sciences INTRODUCTION The Montcalm Branch Experiment Station was established in 1967. This report marks the completion of 18 years of potato research studies at this facility. This report is designed to summarize all of the research conducted at the Montcalm Research Farm during 1984 plus that conducted at other locations. Much of the data reported herein represents projects in various stages of progress, so results and interpretations may not be final. RESULTS PRESENTED HERE SHOULD BE TREATED AS A PROGRESS REPORT ONLY as data from repeated trials are usually necessary before definite conclusions and recommendations can be made. WEATHER Tables 1 and 2 summarize the 15 year temperature and rainfall data recorded at the Research Farm. Temperatures during May were substantially below the 15 year average by 7 F on the maximum and 4 F on the minimum. For the balance of the growing season, temperatures were very near the 15 year average, actually slightly above the average maximum. The overall average for the 6 months growing season was very similar to the 15 year average. The cool May did contribute to a slower emergence, similar to the 1983 experience. Rainfall patterns were very similar to the 15 year average for the growing season. During May the rainfall was 77% above the 15 year average. June was 16% below the average and August was 54% below the average. April, July and September were very similar or slightly above the long term average. All in all, 1984 was a good growing season at the research farm. Supplemental irrigations were applied 17 times during the growing season at the rate of 3/4 inch per application. Total rainfall during the six months growing season was very near the 15 year average, however, May was substantially above the normal, 5.14” vs. 2.91”. August was 2.3” below normal. SOIL TESTS Soil test results for the general plot area were: pH 5.9 P 426 K 213 Ca 1095 Mg 209 Table 1. The 15 year summary of average maximum and minimum temperatures during the growing season at the Montcalm Research Farm. Jul July Min Augus t Max Augus t Min Septembe r Max Septembe r Min 6-Mont h Averag e Max 6-Mont h Averag e Min April Max Apri l Min Ma y Max May Min Jun e Max Jun e Min 54 53 47 54 57 48 58 62 50 50 49 56 53 47 54 53 35 31 30 36 36 28 35 37 31 33 31 35 28 28 34 33 65 65 70 63 62 73 63 80 67 66 69 64 72 60 60 67 47 39 47 42 41 48 41 47 45 44 42 39 46 38 39 43 72 81 72 77 73 75 79 76 78 74 73 73 70 76 77 75 55 56 50 58 52 56 57 50 50 55 50 50 44 49 54 52 Year 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 15-YR. AVG. y Max 80 82 79 79 81 80 81 85 81 82 81 77 80 85 78 81 60 55 57 60 57 57 58 61 56 57 58 51 53 57 53 57 80 80 76 80 77 79 80 77 82 77 81 78 76 82 83 79 57 53 57 60 56 58 53 52 57 55 58 53 48 57 55 55 70 73 69 73 68 65 70 70 75 76 70 67 66 70 69 70 51 54 49 48 45 44 46 53 52 47 49 47 44 46 45 48 73 76 73 74 70 70 71 75 72 71 71 69 70 70 70 72 45 48 48 51 48 49 48 50 49 49 48 46 44 46 47 48 Table 2. The 15 year summary of precipitation (inches per month) recorded during the growing season at the Montcalm Research Farm. Year April May 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 15-YR. AVG. 2.42 1.59 1.35 3.25 4.07 1.81 3.27 1.65 2.34 2.58 3.53 4.19 1.43 3.47 2.78 2.65 4.09 0.93 1.96 3.91 4.83 2.05 4.03 0.46 1.35 1.68 1.65 3.52 3.53 4.46 5.14 2.91 June 4.62 1.50 2.51 4.34 4.69 4.98 4.22 1.66 2.55 3.77 4.37 3.44 5.69 1.19 2.93 3.50 July August September Total 3.67 1.22 3.83 2.36 2.39 2.71 1.50 2.39 1.89 1.09 2.64 1.23 5.53 2.44 3.76 2.58 6.54 2.67 7.28 3.94 6.18 11.25 1.44 2.61 5.90 3.69 3.21 3.48 1.96 2.21 1.97 4.29 7.18 4.00 2.60 1.33 1.81 3.07 1.40 8.62 2.77 0.04 6.59 3.82 3.24 5.34 3.90 3.71 28.52 11.91 19.53 19.13 23.97 25.87 15.86 17.39 16.80 12.85 21.99 19.68 21.38 19.11 20.48 19.64 FERTILIZERS USED The previous crop was a sorghum-sudan hybrid followed by a seeding of winter rye which was plowed down prior to potato planting. Except for the specific fertility studies where the fertilizers are specified in the report, the following fertilizers were used on the potato plot area: plowdown 0-0-60 250 lbs/A banded at planting 20-10-10 500 lbs/A sidedress prior to hilling 46-0-0 225 lbs/A HERBICIDES AND HILLING Most of the hillings were completed by the end of May. The procedure used was to delay the herbicide application until the potatoes were just cracking the ground. The potatoes were then hilled by building a wide and flattened hill and placing just enough soil over the plants to protect them and then the tank mix of metolachlor (Dual) 2 lbs/A plus metribuzin (Lexone 4L) 1/2 lb/A was applied. The sidedress urea was applied at the same time as hilling. This practice required no further tillage until harvest and as a consequence weed control was excellent. INSECT AND DISEASE CONTROL Aldicarb (Temik 15G) was applied at planting at 20 lbs/A. The foliar fungicide applications were initiated on July 2 with nine applications of Bravo. Foliar insecticides used were Imidan on July 24 and August 14, and Cygon on August 22. Diquat at 1 1/2 pints/A + X77 at 8 ounces per 100 gallons was used as a topkiller. 1984 POTATO VARIETY INTRODUCTIONS AND EVALUATIONS R.W. Chase, R.B. Kitchen, and R. Hammerschmidt Department of Crop and Soil Sciences and Botany and Plant Pathology A. DATES OF HARVEST The 1984 dates-of-harvest study was conducted at the Montcalm Research Farm with 20 varieties and numbered selections. Three complete plantings of all varieties were made on May 7 in plots 23 feet x 34 inch rows and 4 replications. Plant spacings were 12 inches within the row. Harvests were made on August 7 (92 days), August 30 (115 days) and September 17 (133 days after planting). The previous crop was a sorghum-sudan hybrid, disked in the fall of 1983 and seeded to winter rye. Fertilizers used were 250 lbs/A 0-0-60 plowdown, 500 Ibs/A 20-10-10 in the planter, and 225 Ibs/A 46-0-0 sidedressed. Aldicarb (Temik 15G) was applied at 20 lbs/A at planting. The sidedress application of urea, hilling and herbicide application were completed just as the potatoes were ready to emerge which is a change from our usual management. Most of the hillings were completed by the end of May. The procedure used was to delay the herbicide application until the potatoes were just cracking the ground. The potatoes were then hilled by building a wide and flattened hill and placing just enough soil over the plants to protect them and then the tank mix of metolachlor (Dual) 2 lbs/A plus metribuzin (Lexone 4L) 1/2 lb/A was applied. The sidedress urea was applied at the same time as hilling. This practice required no further tillage until harvest and as a consequence weed control was excellent. The early hilling did affect some varieties, however, in some cases this was influenced by rains which occurred soon after the hilling with a slight crusting which interfered with the emergence of some varieties (700-79, 701-22, 718-6 and Atlantic). As the season progressed nearly all plants emerged, however, some were weak. In general, this practice was very beneficial in terms of weed control and it did not show any adverse effects in terms of yield. The plots were irrigated and foliar insecticides and fungicides were applied as needed. Results: Yields and quality were much improved over those of 1983 and more nearly like those of 1982 (Table 1). The average total yields at the first date of harvest were 44% higher in 1984 than in 1983 and at the second date of harvest (August 30) they were 16% higher. Specific gravity readings were also substantially higher in 1984; 1.084 at the first date of harvest in 1984 vs. 1.075 in 1983. These higher values reflect the advanced maturity of the 1984 crop compared with that of 1983. This is also reflected in the yields obtained at our last date-of-harvest. In 1983 we had an average total yield increase of 4% from August 31 to September 23 whereas we had no increase in 1984. Yankee Supreme and Conestoga were the only varieties with the greatest yields at 92 days, the first date-of-harvest. On the other extreme, Monona, Russet Burbank, Islander and MS718-6 needed the full season of 133 days to produce their maximum yield of U.S. No. 1’s. Most of the other varieties were at their optimum yields by early September. Table 2 summarizes the internal defects, chip score and black spot damage. Samples for black spot determinations were collected from the second date-of-harvest (August 30) and were processed and scored through the Ore-Ida Foods, Inc. inspection line. Vascular discolorations were not major and those scored as slight would be of no grade concern. Hollow heart was noted as substantial on some selections, however, it was most prominent on tubers harvested on August 30. Variety Observations: MS700-79 - Yielded below average at all dates of harvest with satisfactory dry matter for chip processing. Hollow heart significant at August 30 harvest. MS700-83 - Early emergence with good growth and vigor. An attractive round white. Yielded well above average, good dry matter and few internal defects. Mid-season maturity and good chip score even when held until December. MS701-22 - Round white, medium-late maturity but below average yields. Very few internal defects and good chip color. MS702-80 - Round white with good early emergence and vigor. Medium-late maturity, very few internal defects and very good chip color. MS702-91 - A round to oblong white skin seedling with considerable tendency to pointed tubers. Good yields with medium-late maturity. No further testing because of lack of uniformity in tuber shape and appearance. MS704-10(Y) - A round and somewhat flattened tuber with golden flesh. Mid-season maturity with above average yields. Sets heavy resulting in uniform sizing and smaller percentage of oversized tubers when compared to Yukon Gold. High specific gravity and very few internal defects. Tubers have a deeper eye than Yukon Gold. MS714-10 - Selection deleted from further testing because of lack of good appearance, lower specific gravity and susceptibility to greening. MS716-15 - Round white, shallow eyes, medium-late maturity and very high specific gravity. Yields slightly below average, very few internal defects and good chip color. MS718-6 - Selection deleted from further testing because of later maturity, tendency to oversize and susceptibility to skinning. G670-11 - A round white advanced seedling from Agriculture Canada-Guelph. Late maturity, very vigorous growth and very high yields and specific gravity. Considerable hollow heart noted, some growth cracks and chip color not as desirable as in previous years. Atlantic - A standard variety with very good yields, specific gravity and appearance. Very good chip color, however, hollow heart noted at all dates of harvest. Conestoga - An early maturing (Agriculture Canada-Guelph) round to oblong, white skin variety with deep eyes and some growth crack noted. Well above average yields at first date of harvest, good specific gravity and good chip score. Most suitable as an early maturing, out-of-the-field variety. Islander - An elongated white tuber and late maturing variety from University of Maine and Cornell. Below average yields, medium specific gravity, some hollow heart and not dependable as a consistent chipper. Monona - A standard chipping variety. Onaway - A standard, early maturing, fresh market variety. Russet Burbank - A standard fresh market and frozen processing variety. Shepody - A medium-late maturing long, white variety (Agriculture Canada- Fredrickton) for frozen processing. Matures 2-3 weeks earlier than Russet Burbank, similar specific gravity, sets few tubers than Russet Burbank, but sizes them very quickly. Some susceptibility to scab. Simcoe - A round white variety (Agriculture Canada-Guelph), medium-early maturity with below average yields. Few internal defects except hollow heart at August 30 harvest. Very good chip color, but appears very susceptible to scab. Yankee Chipper - A round to elongated white, released from Maine with above average yields at 92 days. Medium-high specific gravity, few internal defects and good chip color. Yankee Supreme - A round to oblong white variety, released from Maine. Medium-late maturity although it sized tubers early in our studies. Some hollow heart noted at all 3 harvests and chip color not as desirable at later harvests or after 3 months storage. Samples of all selections were collected from the third date of harvest and stored at 40 F for further studies on after cooking darkening, out-of-storage chip quality and reconditioning. TABLE 1. Yield, size distribution and specific gravity of several potato varieties harvested on three different dates in 1984. August August 7 (92 days) Percent Size August 7 August 7 (92 August 30 (115 days) Percent Size Distribution Over 3 1/4 August 30 (115 days) Percent Size Distribution Pick Outs August 30 (115 days) Percent August 30 (115 days) August 30 September September 17 (133 days) Percent September 17 (133 September September 17 (133 7 (92 days) Yield cwt/A August 7 (92 days) (92 days) Percent Size days) Percent Size Distribution August 7 (92 days) Percent August 30 (115 days) August 30(115 days) Percent Size Distribution (115 days) Percent Size Distribution September 17 (133 17 (133 days) days) Percent Size Distribution 17 (133 days) Percent Size days) Percent Variety Total Yield cwt/A No. 1 Distribution No. 1 Distribution<2" 2-3 14 Size DistributionOver 3 1/4 August 7 (92 days) Percent Size DistributionPick Outs Specific Gravity Yield cwt/ATotal Yield cwt/ANo. 1 Size Distribution No. 1 <2" 2-3 1/4 Specific Gravity days) Yield cwt/ATotal Yield cwt/ANo. 1 Size Distribution No. 1 <2" Distribution 2-3 1/4 Size Distribution Over 3 1/4 September 17 (133 days) Percent Size DistributionPick Outs Specific Gravity Onaway Yankee Supreme Yankee Chipper MS704-10 MS700-83 MS702-91 Conestoga MS714-10 Atlantic MS716-15 Monona Russet Burbank Shepody G670-11 Islander MS702-80 Simcoe MS700-79 MS701-22 MS718-6 AVERAGE 497 412 380 364 362 360 359 350 346 332 325 299 298 293 288 278 277 268 221 192 325 453 378 311 308 314 325 310 287 276 282 279 129 240 231 225 239 256 241 196 171 273 91 92 81 85 86 90 86 81 79 85 86 44 81 78 78 87 93 90 88 87 empty table cell 76 86 75 79 73 68 68 65 61 75 76 41 50 75 72 75 84 72 56 72 8 8 18 15 14 10 12 15 21 15 12 52 17 21 20 13 7 10 10 13 empty table cell empty table cell 16 6 7 6 13 22 18 16 18 10 10 3 31 3 6 11 8 18 32 15 1 1 1 1 0 1 2 5 0 1 2 5 2 1 2 1 0 0 3 1 1.072 1.091 1.085 1.093 1.083 1.083 1.084 1.077 1.092 1.094 1.074 1.081 1.082 1.093 1.082 1.081 1.086 1.086 1.083 1.078 1.084 571 415 466 503 497 478 400 427 515 411 382 458 478 534 416 438 357 358 388 402 448 530 377 391 429 441 449 340 371 444 365 348 285 417 480 336 405 327 332 365 374 390 93 91 84 86 89 94 85 87 86 89 91 62 87 90 80 92 92 93 94 93 empty table cell 6 9 16 14 11 5 13 12 13 11 8 32 11 8 19 8 8 7 6 7 72 21 78 13 79 5 75 11 71 18 77 17 73 12 74 13 77 10 81 9 72 20 54 8 47 40 73 17 74 6 79 14 77 15 67 26 59 35 63 31 1.072 1.086 1.088 1.089 1.083 1.086 1.081 1.078 1.097 1.097 1.075 1.088 1.087 1.098 1.087 1.082 1.092 1.090 1.088 1.094 empty table cell 1.087 2 1 1 1 0 1 2 2 1 0 1 6 2 2 1 0 1 1 0 1 empty table cell 535 396 426 437 450 481 357 396 482 404 416 446 392 511 419 358 308 351 360 417 417 503 364 359 370 411 452 310 352 440 345 391 303 327 472 354 330 293 333 339 397 372 94 5 8 92 14 85 16 84 91 9 94 6 86 13 89 10 91 9 86 14 94 6 68 31 83 16 92 7 85 15 8 92 95 5 4 95 5 94 95 4 empty empty table table cell cell 68 82 81 79 78 73 70 72 73 78 76 60 58 76 82 79 73 69 56 52 empty table cell 26 10 4 5 14 22 16 17 18 8 18 7 25 16 2 13 23 26 39 43 empty table cell 1.069 2 1 1.085 1 1.086 0 1.091 0 1.083 1 1.084 1 1.080 1 1.077 0 1.098 0 1.095 1 1.074 1 1.087 2 1.087 1 1.098 1 1.089 0 1.082 0 1.086 1 1.088 1 1.089 1 1.086 empty table cell 1.086 empty table cell empty table cell empty table cell empty table cell TABLE 2. Internal defects 1, chip scores and bruising damage of several potato varieties grown at the Montcalm August 7 Harvest August 7 Harvest August August 30 August 30 Harvest August 30 Research Farm. August 7 Harvest Variety MS700-79 MS700—83 MS701-22 MS702-80 MS702-91 MS704-10 MS714-10 MS716-15 MS718-6 G670-11 Shepody Simcoe Conestoga Yankee Chipper Yankee Supreme Islander Atlantic Onaway Monona VAS DIS 2 sl 2 sl 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 sl 0 0 Russet Burbank 0 INT NEC 1 bc 1 0 2 bc 0 0 0 0 0 0 0 0 1 0 0 0 1 bc 0 0 0 7 Harvest Chip 2 Score August 30 Harvest VASDIS HH 1 0 0 1 0 0 2 0 2 2 0 0 3 0 2 0 2 0 1 0 1.5 1.5 1.5 1.0 1.0 2.0 2.0 1.0 1.5 2.5 2.0 1.5 1.5 1.5 1.5 2.0 1.5 3.0 1.5 3.5 1 sl 2 sl 1 sl 0 0 0 1 sl 1 sl 1 sl 1 sl 4 sl; 4 sev 1 sl 1 sl 2 sl 0 1 sl 2 sl 2 sl 1 sl 0 Harvest INT NEC 2 bc 1 bc 0 5 bc 0 0 1 bc 0 0 0 0 0 0 0 0 0 0 0 0 0 HH 4 1 0 2 1 1 3 0 2 10 1 3 2 0 1 6 2 1 1 3 1 20 tubers cut to determine internal defects. VAS DIS = vascular discoloration INT NEC = internal necrosis H H = hollow heart sl = slight; sev = severe; bc = brown center Harvest Chip 2 Score August 30 Harvest % 3 Bruise Free 1.5 1.5 1.5 1.0 1.5 1.5 1.0 1.0 2.0 1.5 2.0 1.5 3.5 1.0 2.0 2.5 1.5 3.5 1.5 2.5 71 70 50 68 88 49 65 71 57 51 82 44 77 83 50 73 48 76 70 81 2 Chip score based on PC/SFA 1-5 scale. 1 = lightest, 5 = dark, not acceptable. 3 Percent of tubers with no black spot damage. 4 Samples stored at 52° F since harvest and processed on December 11, 1984. September 17 Harvest September 17 Harvest September 17 Harvest September 17 Harvest December 11 4 VAS DIS 2 sl 1 sl 0 1 sl 1 sl 1 sl 1 sl 1 sl 1 sl 4 sl 3 sl 0 1 sl 2 sl 0 5 sl 1 sl 2 sl 2 sl; 1 sev 0 INT NEC 0 1 bc 1 bc 1 bc 0 0 1 bc 2 bc 0 0 0 0 0 1 bc 0 0 0 0 0 1 bc Chip 2 Score H H Chip 2 Score 1 0 0 0 0 0 1 1 0 0 0 0 0 0 1 2 1 0 0 1 1.0 1.0 1.0 1.0 1.0 1.5 2.5 1.0 1.0 2.0 1.5 1.0 1.0 1.0 2.0 1.0 1.0 3.0 1.0 1.5 2.0 1.5 2.0 1.5 1.5 2.5 3.5 2.0 1.5 2.5 2.5 1.0 2.5 1.5 3.0 2.0 1.5 4.5 2.0 3.0 B. NORTH CENTRAL REGIONAL TRIAL Thirteen advanced seedlings from Wisconsin, North Dakota, Nebraska, Minnesota and Louisiana were entered in the 1984 trials and compared with Norland, Norchip, Norgold Russet and Red Pontiac. Plot size, fertilizers and production management were similar to the dates-of-harvest study. Planting date was May 8 and harvest was September 21 (136 days after planting). Table 3 summarizes the yield and quality results. Yields were above average for many of the selections. Selections which did not size tubers well were Russet Burbank, MN11373, MN10874 and MN11795. Those producing the best tuber sizing were Red Pontiac, LA01-38, NE9.72-1, LA82-119, Norland and BN9803-1. Internal necrosis was severe on NE26.72-2 and vascular discolorations was greatest on LA82-119, MN11795 and W855. Hollow heart did not exceed 5% which was noted on ND860-2. Based on sprouts observed at the December 20 date when chips were processed, the MN11795, ND860-2, W855 and Norgold Russet had a very short rest period. Merit ratings were placed on the top five selections in terms of overall worth as a variety. The ratings in Michigan were: 1. W779, 2. LA01-38, 3. ND534-4, 4. Norland and 5. ND388-1. The selection BN9803-1 has Onaway as one of its parents. C. NORTHEAST REGIONAL TRIAL Sixteen selections were evaluated in the Northeast regional trials which represents selections being evaluated in 14 locations. Plot design, fertilizers and production management were similar to the dates-of-harvest study. Planting date was May 9 and harvest was October 2, 147 days after planting. Table 4 summarizes the yield and quality results. Hampton (NY63) is late maturing, similar to Katahdin, primarily for fresh market and does have some scab susceptibility. F7300-8 is an oblong, very late maturing yellow flesh variety. Tuber shape and appearance was not desirable and there was a high percentage of pick-outs. Alasclear is a recent release from Alaska which has good resistance to scab, however, tuber shape was not uniform and attractive at harvest. It’s primary use would be for tablestock. Selections which show the greatest values for further evaluations were Hampton, Alasclear, Sunrise (CF7358-14), WF564-3, G654-2, CF7587-5 and CF7789-1. TABLE 3. Yield, size distribution, specific gravity and chip scores of selections evaluated in North Central Regional Trial. Yield cwt/A Yield cwt/A Percent Size Distribution Percent Size Distribution Percent Size Distribution Percent Size Distribution Chip Scores Chip Scores Cultivar Total No. 1 No. 1 <2" 2-3 1/4 >3 1/4 Pick Percent Size Distribution Specific Outs Gravity October 15 December 20 Red Pontiac LA01-38 R. Burbank W779 (Russ.) Shepody ND388-1 (Russ.) MN11373 NE9.72-1 W855 LA82-119 (Red) ND534-4 (Russ.) Norchip Norland MN10874 (Russ.) NE26.72-2 Norgold Russet BN9803-1 MN11795 (Russ.) ND860-2 AVERAGE 561 485 484 467 442 441 434 415 413 406 398 396 387 369 367 348 344 333 292 410 536 476 262 375 374 348 307 378 355 368 327 326 366 261 312 281 320 167 238 336 96 98 54 80 84 79 71 91 86 91 82 82 95 70 85 81 93 50 81 empty table cell 3 2 44 17 11 18 30 7 14 9 17 15 5 30 14 19 6 50 18 empty table cell 68 63 47 65 49 68 64 61 79 85 69 82 90 67 81 63 62 50 77 28 36 7 16 35 19 6 30 7 6 13 1 5 4 4 18 32 0 4 empty table cell 1 0 3 3 4 3 0 2 0 0 1 3 0 0 1 1 1 1 1 empty table cell empty table cell 1.072 1.085 1.087 1.080 1.085 1.083 1.078 1.066 1.094 1.080 1.075 1.082 1.062 1.079 1.081 1.071 1.083 1.073 1.079 1.079 4.0 1.5 2.5 1.5 - 2.0 3.0 2.5 1.0 2.5 2.0 1.5 3.0 4.0 2.5 4.0 1.5 2.0 1.0 - 1.5 - 1.5 2.5 2.5 3.5 3.0 1.0 3.0 2.5 1.5 - 4.0 1.5 4.0 1.5 2.0 1.0 empty table cell empty table cell TABLE 4. Yield, size distribution, specific gravity and chip scores of selections evaluated in the Northeast Regional Trial. Yield cwt /A Yield cwt /A Percent Size Distribution Percent Size Distribution Percent Size Distribution Percent Size Distribution>3 1/4 Chip Score Chip Score Variety Total U.S. No. 1 U.S. No. 1 95 80 86 67 94 92 94 91 82 93 83 92 85 92 88 74 <2 5 6 12 33 6 6 5 6 19 8 16 8 15 7 11 25 2-3 1/4 Percent Size Distribution Pick Outs Specific Gravity September 24 December 12 60 53 75 63 66 85 83 66 78 80 82 73 80 70 78 61 empty table cell 35 27 11 3 27 8 11 26 4 13 2 19 5 22 11 12 empty table cell 1 15 2 1 1 2 2 3 0 0 1 0 0 2 1 1 empty table cell 1.074 1.081 1.063 1.069 1.074 1.083 1.088 1.071 1.063 1.074 1.081 1.068 1.070 1.081 1.065 1.074 1.074 2.5 2.0 2.0 3.0 2.5 3.0 1.5 2.0 2.5 1.0 2.5 2.5 2.0 1.0 2.0 1.5 3.0 2.5 2.5 4.0 2.5 3.0 1.5 2.0 2.5 1.5 2.5 2.5 3.5 1.5 2.0 1.5 empty table cell empty table cell Hampton F7300-8(Y) CF74135-3 WF564-3 B6949-WV3 Alasclear BR7088-18 AF92-3 G654-2 CF7358-14 CF7587-5 CF7789-1 CF7722-19 AF330-1 CF7719-6 GoldRus AVERAGE 541 538 505 469 468 464 451 440 409 408 388 375 369 363 335 311 427 512 428 436 314 438 425 423 401 334 377 324 346 315 333 295 230 371 empty table cell empty table cell D. USDA-BELTSVILLE TRIALS Three separate trials evaluating selections from the USDA-Beltsville potato breeding program were conducted in 1984. Cultural, fertility and management practices used were the same as described in the dates of harvest study. Planting date was May 9 and harvested on October 2, 147 days after planting. Table 5 summarizes the data from the preliminary trials which represents selections with limited data in Michigan. Tubers from the russets, B9539-9 and B8687-3 did not size well with high percentages of tubers under 2 inches. B8687-3 also had scab and the tubers were pointed and did not have good general appearance. Scab was also noted on B9792-119, B9540-29, B9539-9 and B9752-7. Hollow heart was noted on 4 of 20 tubers of B9540-29, 2 of 20 for Atlantic and 1 each for B9752-7, B9581-10 and B9792-84. Internal browning or necrosis was noted in 5 of 20 tubers of B8682-4. Table 6 summarizes the results of the selections entered in the USDA-Beltsville Inter-Regional trial. Similar trials are conducted in the northeast and eastern states along the coast and into Florida. As noted in other trials, the russet selections did not size their tubers well with a high percentage of tubers under 2 inches. The WF31-4, 46-3 and 46-4 selections are white flowered "Atlantic" types which are being evaluated for internal defects as compared with Atlantic. Yields, size distribution, specific gravity and chip scores are very similar. Of the 20 tubers selected at random and used for the chip sample on September 24, WF31-4 had 2 hollow, WF46-3 had 1 and Atlantic and WF46-4 had none. When 8 large tubers (over 3 1/4 inch) were selected and cut, Atlantic had 3 hollow, WF31-4 had 5, WF46-3 had 3 and WF46-4 had 4 which suggests very little predictive difference among the 3 selections and Atlantic. There was no internal browning or necrosis in any of these selections. Internal defects were minimal in all of these selections and all produced very acceptable chips except B9400-5, B9596-2, B9553-6 and B9569-2. WF46-3 did have considerable growth crack as did GoldRus, B9648-9 and B9553-5. B9540-62 is scheduled for release as NemaRus. This long russet selection has produced best in Hastings, Florida. Table 7 summarizes the yield data for the five tuber samples which were selected at harvest from the screening trial. A total of 42 selections were evaluated and compared to Atlantic, Monona and Superior in the same trial. These data represent a single 8-hill plot which is not replicated. Nearly all selections were fully mature when harvested. It is intended that the most promising of these selections will be entered into larger and replicated plots in 1985. TABLE 5. Yield, size distribution, specific gravity and chip scores of preliminary selections from the USDA-Beltsville breeding program. Yield cwt/A Yield cwt/A Percent Size Distribution Percent Size Distribution Percent Size Distribution Percent Size Distribution Percent Size Distribution Chip Scores Chip Scores Variety Total U.S. No. 1 U.S. No. 1 <2 2-3 1/4 Over 3 1/4 Pick Outs Specific Gravity November 6 December 19 B9792-84 Atlantic B8682-4 B9581-10 B9638-11 B8687-3(Y) B9792-119 B9752-7 (Russ.) B9540-55 (Russ.) B9539-9 B9540-29 (Russ.) AVERAGE 556 522 497 481 470 448 421 373 356 345 290 433 513 492 438 424 428 283 382 268 219 202 210 351 92 94 88 88 91 63 91 71 62 59 72 empty table cell 7 5 11 9 8 35 7 27 37 41 23 empty table cell 70 71 79 74 81 55 57 56 57 55 58 empty table cell 22 23 9 14 10 8 34 15 4 4 15 empty table cell 1 0 2 2 1 3 3 1 2 0 4 empty table cell 1.099 1.101 1.079 1.080 1.095 1.074 1.088 1.070 1.075 1.085 1.080 1.084 1.5 1.5 2.0 2.0 2.5 2.5 1.5 3.0 2.0 1.5 2.0 empty table cell 1.5 1.5 2.5 2.5 2.5 3.0 2.5 3.0 2.5 3.0 2.5 empty table cell TABLE 6. Yield, size distribution, specific gravity and chip scores of potato varieties in the USDA-Beltsville Inter-Regional Trial. Yield cwt/A Yield cwt/A Percent Size Distribution Percent Size Distribution Percent Size Distribution Percent Size Distribution Chip Scores Chip Scores Variety Total U.S. No. 1 U.S. No. 1 <2" 2-3 1/4 Over 3 1/4 Percent Size Distribution Pick Outs Specific Gravity September 24 December 13 WF31-4 Atlantic WF46-4 WF46-3 B9192-1 B9140-32 B9400-5 (Russ.) B9384-4 B9596-2 (Russ.) B9553-6 (Russ.) B9340-13 B9569-2 (Russ.) B9648-9 (Russ.) GoldRus (Russ.) B9540-62 (Russ.) B9398-2 (Russ.) AVERAGE 491 484 470 449 424 419 408 408 405 389 368 363 347 327 316 309 399 446 451 426 397 396 383 358 302 312 304 348 257 241 235 243 239 334 90 93 91 89 93 92 88 74 77 78 92 71 69 72 76 70 empty table cell 9 7 8 9 5 9 11 26 24 18 7 28 29 25 23 20 empty table cell 73 66 73 70 48 88 58 74 68 56 79 61 64 60 66 64 empty table cell 18 28 18 19 45 4 29 0 9 22 14 10 6 12 11 14 empty table cell 1 0 1 3 2 0 1 0 0 5 1 2 2 3 1 3 empty table cell 1.102 1.099 1.095 1.097 1.077 1.092 1.075 1.076 1.075 1.074 1.081 1.075 1.070 1.078 1.075 1.082 1.083 1.5 1.5 1.5 1.5 1.5 1.0 2.5 1.0 3.0 2.0 1.5 3.0 2.0 1.5 2.0 1.5 empty table cell 1.5 1.5 1.0 1.5 2.0 1.0 3.0 1.5 4.0 2.5 1.5 1.5 1.5 1.5 2.0 2.0 empty table cell TABLE 7. Yield, size distribution and specific gravity of several seedlings selected at harvest from eight­ hill plantings of USDA-Beltsville selections. Yield cwt/A cwt /A Yield Percent Size Distribution :Percent Size Distribution Chip Scores Chip Scores Cultivar Total No. 1 <2” Percent Size Distribution 2-3 1/4 >3 1/4 Pick Percent Size Distribution Outs Specific Gravity November 2 December 17 Comments B9988-23 B9581-10 B9933-20 B9988-14 B9956-14 B9582-18 Atlantic B9934-51 B9967-1 B9581-2 B9959-20 (Russ.) B9955-21 B9999-3 (Russ.) B0019-2 (Russ.) MS002-171(Y) B0016-13 (Russ.) Superior Monona 616 559 530 521 511 492 492 426 417 407 407 398 398 369 360 350 341 294 578 521 483 502 474 455 455 407 388 388 388 379 360 313 303 284 294 265 3 7 7 2 7 8 6 4 7 2 5 5 7 15 6 14 8 10 85 64 82 82 70 81 73 78 84 67 58 79 76 85 63 68 83 87 9 29 9 15 23 11 19 18 9 28 37 16 14 0 21 13 3 3 3 0 2 1 0 0 2 0 0 3 0 0 3 0 10 5 6 0 1.081 1.085 1.082 1.079 1.078 1.083 1.097 1.060 1.092 1.077 1.069 1.080 1.077 1.071 1.079 1.065 1.072 1.068 1.5 2.0 1.5 1.0 3.0 2.0 1.0 1.5 1.0 1.0 1.5 1.0 2.5 3.0 1.5 2.0 1.5 1.0 Planted: May 9, 1984 Harvested: September 11, 1984 1.0 1.5 1.5 1.0 2.0 2.0 1.5 1.5 1.5 1.0 1.5 1.0 3.0 3.5 2.0 2.5 2.0 1.0 short dormancy long dormancy empty table cell short dormancy empty table cell empty table cell empty table cell long dormancy short dormancy sl. growth crack long, dark russet short dormancy oblong russet oval russet knobs and off type long russet empty table cell empty table cell empty table cell E. OVERSTATE DEMONSTRATION TRIALS Yield data were collected from three commercial farms in 1984. These were established as demonstration plantings and were not replicated. Locations were at Ray Bourdo and Sons in Allegan County, Wilk Farms in Presque Isle County, and Kellen Farm in Ingham County. The planting date at the Bourdo Farm in Allegan County was May 12 and harvest was completed October 16. The plots were located on a muck soil and were fertilized with 200 lbs of urea plowdown, 150 lbs K20 and 200 lbs of urea topdressed. Foliar nitrogen was applied at 5 lbs/acre on each of 4 applications. Table 8 summarizes the yield data. The soil moisture was above optimum at harvest as a result of frequent rains. Specific gravity readings are below normal likely because of the later maturity and wet soil conditions, chip colors, however, were very acceptable. Plots located at the Wilk Farm in Presque Isle County were planted on May 23 and harvested on October 1. Fertilizers used were 150 lbs/A 0-0-60 plowdown and 400 lbs/A 19-19-19 in the planter. Yield results are shown in Table 9. These plots were not irrigated and yields are below normally expected. Some selections also had poor stands which did contribute to reduced yields. There was a high percentage of sun green tubers, particularly Snowchip and MS700-83, however, the degree and incidence in all the varieties suggests it was a shallow tuber set and/or an inadequate soil cover which affected all of the varieties. Table 10 summarizes the results at the Keilen Farm in Ingham County. Fertilizers applied to this muck soil were 400 lbs/A 0-0-60 at plowdown and 400 lbs/A of 6-24-6 in the planter. From mid June through August, a foliar application of 1 lb/acre of "Nutraleaf" 20-20-20 was applied. TABLE 8. The yield, size distribution, specific gravity, chip quality and internal defects of several potato varieties grown at the Bourdo Farm, Allegan County. Yield Yield Percent Size Distribution Percent Size Distribution Percent Size Distribution Percent Size Distribution Internal Defects ** Internal Defects ** Variety Total cwt No. 1 cwt No. 1 Under 2" 2-3 1/4" Over 3 1/4" Specific Gravity Chip* Score Vascular Discoloration Internal Necrosis Hollow Internal Defects ** Heart Shepody Chipbelle MS700-79 MS 700-83 MS716-15 MS701-22 540 498 335 302 277 249 481 471 301 287 259 226 89 95 90 95 94 91 11 5 10 5 6 9 59 60 57 48 56 58 30 35 33 47 38 33 1.076 1.087 1.073 1.069 1.080 1.071 2.0 1.0 1.5 1.0 1.5 1.5 8 sl 4 sl 1 sl 1 sl - - — - - - - - 2 1 1 - - - Planted: May 12, 1984 Harvested: October 16, 1984 *Rated on a 1-5 scale. **Internal defects were determined by cutting 20 randomly selected tubers. TABLE 9. The yield, size distribution, specific gravity and internal defects of several potato varieties grown at the Wilk Farm, Presque Isle County. Yield cwt/A Yield cwt/A Percent Size Distribution Percent Size Percent Size Distribution Percent Size Distribution Percent Size Distribution Internal Defects ** Internal Defects ** ** Internal Defects Variety Total U.S. No. 1 u. s. No. 1 Distribution Under 2" 2-3 1/4 Over 3 1/4 Pick Outs Specific Gravity Maturity * Rating Aug. 14 Vascular Discol­ oration Internal Browning Hollow Heart Comments Snowchip 371 296 Shepody 305 269 Katahdin Atlantic Sebago MS700-83 288 279 259 246 MS704-10 (Y) 221 Yukon Gold MS702-80 MS716-15 G654-2 AVERAGE 198 158 143 68 231 265 266 237 200 197 81 89 192 128 125 58 203 80 88 92 95 91 97 81 87 86 3 3 1 3 5 3 2 4 5 5 53 55 40 73 78 75 79 53 26 33 52 22 13 22 18 34 13 10 68 80 17 1.070 1.0 4 slight 14 5 9 7 2 4 0 - 9 0 1.076 2.0 7 slight 1.071 1.089 1.069 1.080 1.085 3.0 2.5 1.083 1.078 1.087 1.0 2.5 - 3.5 2.5 2.0 1 slight 1 slight 11 slight 1 slight 3 slight 1 slight 2 slight 4 slight 0 0 1.064 5.0 5 slight 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Considerable greening and off type Some green, slight scab, some off type Some scab, sun green empty table cell empty table cell Considerable greening Slight greening empty table cell Smooth, good type Very poor stand, good tuber type Very poor stand empty table cell 86 14 empty table cell 0 empty table cell empty table cell empty table cell empty table cell empty table cellempty table cellempty table cellempty table cell 1.077 *Maturity Rating: 1 = active growth, mostly green vine 5 = completely mature, vines dead **Internal defects were determined by cutting 30 randomly selected tubers. TABLE 10. The yield, size distribution, specific gravity and internal defects of several potato varieties grown at the Keilen Farm, Ingham County. Percent Size Distribution Percent Size Distribution Percent Size Distribution Percent Size Distribution Percent Size Distribution * Internal Defects * Internal Defects Yield Total cwt /A U. S. No. 1 Yield cwt/A U. S. No. 1 Under 2" 2-3 1/4 Over 3 1/4 Pick Outs Specific Gravity Vascular Discoloration Internal Necrosis *Hollow Internal Defects Heart 513 450 396 381 364 328 319 317 314 296 368 469 393 371 289 304 282 304 295 284 282 327 91 87 94 76 84 86 95 93 90 95 7 5 6 15 15 13 5 7 3 4 59 45 76 72 75 69 64 74 49 63 32 42 17 9 2 17 31 19 42 32 2 8 1 4 2 1 0 0 6 1 1.079 1.073 1.077 1.061 1.053 1.069 1.077 1.083 1.070 1.080 0 5 slight 2 slight 2 slight 8 slight 3 slight 4 slight 0 2 slight 1 slight 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 1 0 0 0 0 empty table cell empty table cell empty table cell empty table cell empty table cell empty table cell empty table cell empty table cell 1.072 Variety G670-11 Shepody MS700-83 Superior G654-2 Islander MS700-79 MS716-15 C-13 MS701-22 AVERAGE Planted: May 21, 1984 Harvested: October 9, 1984 *Internal defects were determined by cutting 25 randomly selected tubers. 1984 POTATO VARIETY EVALUATIONS DELTA COUNTY, MICHIGAN R.H. Leep, J.R. Lempke, D.L. Pellegrini, R.W. Chase, and R.W. Hammerschmidt A potato variety evaluation was conducted in Delta County, Michigan on the John VerBrigghe farm. The varieties were planted in a randomized complete block design with four replications. The plots were harvested on October 16, 1984. Yields, specific gravity and internal defects were determined. The plot area received a total of 129-60-120 lbs/A fertilizer. The soil test was pH 6.8, P-272, K-224. The plowdown crop was a one-year old stand of alfalfa. Temik was applied at planting. 0.25 lbs/A Lexone was applied postemergence. The plots were irrigated and managed in a similar manner as the cooperator maintained the entire field. RESULTS The yield performance, specific gravity and internal defects are summarized in Table 1. The total yield ranged from 224 to 446 cwt/acre with MS-718-6 recording the highest yield. The average total yield over 19 varieties was 333 cwt/acre. MS-718-6, Shepody, Yukon, Gold and MS-702-91 varieties recorded significantly higher yields of large tubers. Overall quality and appearance of tubers was excellent. Specific gravity ranged from 1.072 to 1.092. The only significant internal defect found was hollowheart. Only one variety had an appreciable amount of hollowheart, MS-718-6. Scab severity was high in replication 1 and less in replications 2, 3 and 4. Road salts apparantly ran off and affected scab intensity on tubers in replication 1 which was nearest the roadway. Table 1. Potato variety trial yields. Delta County, Michigan. 1984. VARIETY TOTALYield cwt/A UNDER NO. 1Yield cwt/A 2" Yield cwt/A OVER 10 oz. OR 3 1/4" Yield cwt/A PICKOUTYield cwt/A SG INTERNAL DISORDER MS-718-6 Islander MS-716-15 MS-701-22 700-83 704-10 Yankee Supreme Connestoga 702-80 Yankee Chipper MS-700-79 MS-714-10 Shepody Yukon Gold SG-70-11 MS-702-91 Simcoe Superior Russett Burbank empty table cell 446a 1 309ef 319def 270efg 280efg 405abc 315def 291dg 224g 336cde 297def 357bcd 439a 353cd 353cd 35cd 260fg 282efg 424ab 333 201 213 274 177 202 311 185 187 161 253 232 274 231 180 250 208 216 219 329 226 18 27 17 9 18 15 24 24 20 23 10 37 20 13 17 13 7 46 39 20 226a 68def 28ef 81cde 60def 79cde 90cd 78cde 43def 60def 54def 46def 182ab 160b 86cd 130bc 37def 16f 26ef 82 1 1 0 3 0 0 26 2 0 0 1 0 6 0 0 1 0 1 30 4 1* 1* 111* 1.084 1.077 empty table cell 1.092 empty table cell 1.079 empty table cell 1.077 empty table cell 1.081 1.078 empty table cell 1.076 1.072 empty table cell 1.080 empty table cell 1.081 1.074 empty table cell 1.083 1.082 1.091 1.079 empty table cell 1.083 empty table cell 1.076 empty table cell 1.087 empty table cell 1.081 empty table cell 1* 1* 1* 1* 1 Column means followed by the same letter are not significantly different as determined by the Least Significant Difference Test (.05) *Hollowheart CONTROL OF SCAB AND RHIZOCTONIA DISEASES Department of Botany and Plant Pathology R. Hammerschmidt Introduction Scab and Rhizoctonia diseases of potatoes continue to be a problem in Michigan potato production. Experiments were performed this year in the field and greenhouse to examine some known methods of control for these diseases. In addition, preliminary experiments on foliar applied chemicals directed at controlling scab were carried out. Variety Evaluations for Scab Resistance Disease resistance is perhaps the best method for controlling a particular disease. This is one approach which has been implemented in an attempt to control scab. Twenty-eight varieties and number selections were evaluated for scab resistance at two locations. Each variety was replicated four times in ten foot plots at each location. Approximately ten pound samples of uniformly sized tubers were taken from each plot and examined for type of scab and per cent tuber coverage by scab lesions. Due to uneven scab pressure in the plot at location 2, each replicate is listed individually. Results: Several named varieties and numbered selections showed very good scab resistance at both locations (Table 1). Varieties which exhibited consistently high resistance were: Islander, Onaway, Russet Burbank, Superior, MS 700-79, MS 703-80, MS 702-91, and MS 714-10. Varieties with an intermediate level of resistance were: Snowchip, MS 700-83, and MS 718-6. The other varieties all are classified as susceptible. Soil Treatments for Scab Control Soil treatments designed at killing the scab organism have generally been ineffective or too costly to use. There is evidence from other research that certain nutritional variables and/or soil pH may have a direct relationship to the severity of scab. Several of these reported control methods were tried in the greenhouse and in the field. Soil treatments (non-fungicide) reported to control scab were tested in the field and in the greenhouse using the Atlantic and Katahdin varieties, respectively. Materials used in the field were applied to the furrow and worked in by hand just prior to planting. Rates are given in Table 2. Tuber samples were taken after plants had reached full maturity. Each treatment was replicated four times in ten foot plots. Tuber sample sizes for scab analysis were ten pounds per plot. For greenhouse tests, plants were grown in five inch pots which contained a bilayer of greenhouse potting mixture and infested soil. Seed pieces were placed on a three inch layer of the potting mix and covered with infested soil. The infested soil was either left untreated prior to adding to the pots or treated as described in Table 3. All pots were top watered until one week after emergence of the plants. At this time, all pots, except those in the "heavy irrigation" treatment, were bottom watered. This allowed development of the semi-dry conditions that favor scab development. The soil in the "heavy irrigation" treatment was never allowed to dry out. Tubers (over one cm in diameter) were harvested at seven weeks after planting. Results In the field, none of the treatments gave complete control (Table 2). However, marked reductions in the amount of scab were observed with the manganese treatments. The decrease in symptoms was characterized by not only fewer scabs but also more shallow scabs. In the greenhouse, good control was obtained with all treatments except P2O5 (Table 3). This suggests that scab control might be possible by a proper balance of certain soil nutrients. Foliar Treatments for Scab Control There is little doubt that a foliar applied treatment for scab control would be very useful. Research by McIntosh in England has demonstrated that foliar applications of 3,5-diphenoxyacetic acid (a growth retardant) and ethionine (an antimetabolite could reduce scab significantly. Greenhouse and field experiments based on this idea were carried out. Katahdin potatoes were grown in the greenhouse as described above. When the plants were beginning to set tubers, they were sprayed with a water soltuion of one of the materials listed in Table 5. In the field, the Atlantic variety was used. Plants were sprayed at about two weeks after emergence. Small tubers and swollen stolon ends were visible at this time. Results The greenhouse work confirmed the results of McIntosh which suggested that a foliar applied chemical could be effective against scab. In addition CCC (a growth retardant known to enhance disease resistance in other plants against pathogens) and phenylserine (an amino acid analog which also has resistance promoting properties) decreased the amount of scab in both greenhouse and field trials (Tables 4 and 5). D-phenylalanine, another amino acid with some reported disease resistance promoting activity, was far less effective than the other compound tested. Seed Treatment for Rhizoctonia Control Seed pieces of Onaway potato, selected for the presence of Rhizoctonia sclerotia were used to further test the effectiveness of certain seed piece treatments in the control of the Rhizoctonia disease. Infected seed was treated with 2% formaldehyde (5 min), one of three fungicides or left untreated. Tubers were harvested at maturity and evaluated for total yield and size distribution. Results Treatment of seed pieces with formaldehyde to kill all of the Rhizoctonia, Tops 2.5, or NTN 19701 resulted in an increase in the yield of #1 tubers and a reduced number of small tubers and culls as compared to the control or Captan treated seed pieces. The culls exhibited a high degree of deformation, russetting and some tuber pitting. The results are shown in Table 6. TABLE 1 SCAB VARIETY EVALUATIONS VARIETY LOCATION 1 LOCATION 2a LOCATION 2b LOCATION 2c LOCATION 2d - Atlantic Chipbelle Connestoga Denali Islander Jemseg Katahdin Oceania Onaway Russet Burb. Simcoe Snowchip Superior Shepody Yankee Chipper Yankee Supreme Yukon G 670-11 700-83 700-79 701-22 702-80 702-91 704-10 704-17 714-10 716-15 718-6 3.95 a 2.42 2.11 3.81 0.53 3.40 4.80 3.01 0.41 0.18 - 1.33 0.68 - 2.33 4.01 2.53 1.50 1.51 0.41 1.57 - 0.53 - 4.63 0.24 3.00 2.25 - 2.31 - 0.84 - - - 0.21 3.00 - 0.36 3.35 2.67 4.50 3.93 2.25 1.25 0.38 2.54 0.04 1.18 4.33 - 0.37 3.30 1.50 - - 1.12 - 0.50 - - - - - 0.00 3.20 - 0.11 1.50 1.32 4.40 2.86 2.80 1.05 0.31 2.38 0.00 0.19 3.05 - 0.25 3.00 0.65 - - - 1.18 - 1.06 - - - - - 2.65 - 0.21 2.90 1.07 1.25 2.11 2.51 0.76 0.47 1.56 0.00 0.18 1.58 - 0.22 0.92 0.95 - 0.71 - 0.52 - - - - 0.00 1.78 - 0.17 1.10 0.91 0.56 1.35 1.63 0.36 0.00 0.75 0.00 0.10 1.58 - 0.06 1.00 0.13 a Evaluations based on the following: 0=no scab; 1=1-5% coverage; 2=5-10% coverage; 3=10-20% coverage; 4=20-35% coverage; 5=over 35% coverage. TABLE 2 EFFECT OF SOIL AMENDMENTS ON SCAB TREATMENT RATE APPLIED SCAB RATING a Manganese sulfate Manganese sulfate Manganese chloride Sulfur Control 40 lb Mn/A 20 lb Mn/A 40 lb Mn/A 500 lb S/ A empty table cell 1.75 a 2.20 b 1.92 a 4.15 c 4.58 c a Scab rating scale same as in table 1. Means followed by different letters are significantly different, p=0.05 TABLE 3 EFFECT OF SOIL AMENDMENTS ON SCAB RATE APPLIED a SCABBY TUBERS/TOTAL TUBERS b to pH 5.2 to pH 5.2 40 lb Mn/A 20 lb Mn/A 150 lb Mn/A ---- Saturation 8/36 7/39 3/32 5/26 15/28 23/30 5/42 TREATMENT Sulfuric acid Phosphoric acid MnS04 MnS04 P2O5 Control Heavy Irrigation a Materials were mechanically mixed into infested soil prior to potting. Ib/A values are estimates. b Ten pots per treatment. Only tubers over 1cm in diameter were counted. TABLE 4 TABLE 5 FOLIAR TREATMENTS FOR SCAB CONTROL FOLIAR TREATMENTS FOR SCAB CONTROL TREATMENT CCC D-Phenylalanine Phenylserine Control SCAB RATING a 2.2a 3.5b 1.8a 4.6c a Rating scale as in Table 1. Means followed by different letters are significantly different, p=0.05. TREATMENT a ccc D-Phenylalanine Phenylserine Ethionine Control SCABBY TUBERS/TOTAL 3/42 29/31 4/49 2/38 25/39 a Materials sprayed on foliage at time of tuber set. Materials used at a concentration of 1mM. b Ten pots per treatment. Only tubers over 1 cm in diameter were counted. TABLE 6 SEED TREATMENT FOR RHIZOCTONIA CONTROL TREATMENT a Yield (cwt/A) Yield (cwt/A) Yield (cwt/A) B Yield (cwt/A) 1 Control NTN 17901 Tops 2.5 13.3 9.8 10.8 Formaldehyde 12.8 Captan 8.3 164.5 204.8 194.2 189.3 146.9 OVER 35.7 26.6 44.2 38.3 25.5 CULL 102.2 57.4 42.3 89.6 88.9 TOTAL Yield (cwt/A) 315.7 298.6 291.5 330.0 269.5 a All treatments are averages of five replicates except Captan treatment which is from three. BIOLOGY AND CONTROL STRATEGIES FOR INSECT PESTS OF POTATOES E. Grafius, E. Morrow, and A. May Department of Entomology Research in 1984 included: 1) Laboratory evaluation of the effect of temperature on toxicity of synthetic pyrethroids to Colorado potato beetle. 2) 3) Insecticide screening at the Montcalm Potato Research Farm in Entrican. This trial included IGR's and biological insecticides. A preliminary field study of the effects of IGR’s and biological insecticides on Colorado potato beetle egg mortality. 4) Pheromone trapping at two locations. 5) Development of an on-farm assay for use in determining tolerance to different insecticides in localized populations of Colorado potato beetle. Summary of Results: 1) Four technical grade synthetic pyrethroids, compounds commonly known as Pydrin, Cymbush, Ambush and Pay-Off were used in a laboratory evaluation of temperature effects on the toxicity of these materials when applied to Colorado potato beetle. The organophosphate, Guthion was used as a standard. All the pyrethroids exhibited significant (2-8x) decreases in toxicity between 14-30°C while toxicity of the organophosphate increased 4x from 14-23°C and 2x from 30-35°C. 2) Results from the insecticide screening trial (27 materials tested) suggest that the various IGR's and B.t. exotoxins show promise for controlling resistant populations of the Colorado potato beetle. However, the materials are specific for Colorado potato beetle and are ineffective on other pests in potatoes, ie. aphids and potato leafhopper. Temik and Baythroid both gave good control of a wide spectrum of insects as compared to other treatments. Yield was also significantly higher in these treatments. 3) Egg masses of Colorado potato beetle were collected from the insecticide trial plots directly after a spray. Egg hatch was monitored over a 10 day period. Variability was high within the treatments and no significant differences were seen. Egg masses were hard to find and were not all the same age so it is difficult to draw a strong conclusion from the data. 4) Pheromone traps were set up in Montcalm Co. and E. Lansing and monitored throughout the season. Graphs are included to show peak adult flight. 5) Standard data have been prepared for use as a guideline in determining the tolerance of Colorado potato beetle from local populations in comparison to the Montcalm Co. population. A relatively simple test has been designed for use by anyone on the farm to use as a trouble-shooting tool or to determine whether unusual tolerance exists in comparison to a standard susceptible population. TEMPERATURE/TOXICITY STUDIES Laboratory reared beetles originally collected from Montcalm Co. were used in this laboratory evaluation. Beetles from this location had been exposed to several different insecticides including, Temik, Sevin, Pydrin, Thiodan, and Monitor, in 1983. The population was reared for two generations on untreated foliage in the greenhouse. The objective of the test was to evaluate the effect of temperature on the toxicity of synthetic pyrethroids as compared to an organophosphate standard, Guthion. Prior to treatment the beetles were acclimated to the appropriate temperature at which they would be tested. Topical application of one drop of test material to the abdomen was done at room temperature with the beetles immedately returned to cups and placed in the respective growth chamber. Temperatures tested were 14, 23, 30, and 35 °C. The pyrethroids tested were Pydrin, Ambush, Cymbush, and Pay-Off. The results show the toxicity of Guthion increased significantly from 14 and 23°C, leveled off from 23-30°C, and increased again between 30-35 °C. All the pyrethroids showed significant decreases in toxicity from 14- 30°C. These results suggest that there may be a problem with lack of control of Colorado potato beetle at higher temperatures using pyrethroids, particularly Pydrin, where the toxicity decreases dramatically from 14-30 C°( 5X). Factors such as residual activity and mode of uptake affect control in the field and this study does not investigate them directly, this makes it difficult to apply this information to a field situation. However, it allows us to direct our spray programs with an increased knowledge of how we may get the best possible control with each spray applied. POTATO INSECTICIDE TRIAL Potatoes were planted May 9, 1984 at the MSU Montcalm Potato Research farm in Entrican. Plots were 3 rows wide (34 inch spacing) by 40 feet, with 2 untreated rows between plots. Treatments were arranged in a randomized complete block design with 4 blocks per treatment. Treatments included pyrethroids, insect growth regulators, B.t. exotoxins, carbamates, and organophosphates. The treatments were applied at planting, as a sidedress with fertilizer at hilling (May 30), or as a weekly foliar treatment from June 21 to August 16 (Table 1). Foliar treatments were applied with a tractor mounted boom sprayer at 30 gal/acre, 40 psi, with a cluster of nozzles over each of the 3 rows. One nozzle was pointed directly over the row and the other two nozzles were directed at the sides of the plants. Weekly insect counts (June 13-August 16) were made from two randomly selected plants in the center row of each plot. Colorado potato beetle damage ratings were also made weekly (July 3-August 21) on 2 plants per plot. Damage ratings were assigned in the range of 0-3. Zero denoting no feeding injury, 2 denoting general feeding on entire plant ( 50 % defoliation) and 3 indicating almost complete defoliation (only stems left). Potato leafhopper damage ratings were 0-2, with 0 denoting no browning of foliage, 1 denoting general browning of plants and 2 indicating heavy necrosis and premature death of many of the plants in the plot. Yields were taken on September 12 from the center row of each plot. Colorado potato beetle adult numbers ranged as high as 47 per plant (July 31) and larval numbers were as high as 84 per plant (August 7). Seasonal mean numbers (ave. over 10 dates) of large potato beetle larvae exceeded the economic threshold of 2 beetles per plant in many of the treatments (Figures 1-2). Seasonal mean numbers of potato leafhoppers (ave. over 9 dates), ranged from .05/plant in the Temik standard (3 lb ai/a at planting) to 10/plant in the high rate of the IGR: CME 13406 (Figure 3). In general, all the soil treatments held potato beetle damage to a minimum throughout the season and all the foliar treatments showed less damage than the untreated except for Pounce and Kryocide. In general, the treatments designed for Colorado potato beetle control (eg. IGR's and B.t. exotoxins) did not adequately control potato leafhopper. Although only moderate potato beetle control was obtained in these plots, the damage ratings show that the potato beetle foliar feeding was not generally a significant problem. However, serious leafhopper injury occurred and the damage is reflected in the yield data (Figure 4). The various IGR’s and B.t. exotoxins may show promise in controlling resistant populations of Colorado potato beetle. However, they may not be competitive in price or efficacy for non-resistant populations. Their role in Michigan will probably be as supplemental materials, to alternate with traditional materials and slow the rate of resistance build-up. FIELD STUDY OF EGG MORTALITY WITH IGR'S Potato insecticide trial plots at the M.S.U. Montcalm Expt. farm were also used for a preliminary field study on the effects of insect growth regulators and B.t. exotoxins on potato beetle egg mortality. After the last spray date, on August 16, 2-5 egg masses were collected from each treatment and placed in paper cups. Egg masses were brought back to the lab and placed in a growth chamber at 16 hr. photoperiod and held at a constant temperature of about 75°F. Egg masses were observed every 1-2 days to count and remove any newly hatched larvae (to prevent cannabilism). After a 10 day period, eggs had either hatched or were considered inviable. No significant differences were observed between treatments. One IGR (CME 13406) showed 18 % hatch and another IGR (RH 4971) showed 96 % hatch. Age of egg masses was not monitored and is one of the reasons we will do this study again in 1985. PHEROMONE TRAPPING Two locations were monitored during 1984. Traps were located at the Montcalm Co. Research farm and at the Entomology research farm in East Lansing. Traps set included: black cutworm (BCW), variegated cutworm (VCW), European corn borer (ECB), corn earworm (CEW), and cabbage looper (CL). The number of moths caught in CEW and CL traps were so few that graphs would not be practical. Figures 5-7 show a graphical presentation of adult male moth flight at the two locations. ON-FARM TEST FOR INSECTICIDE RESISTANCE The objectives of the study were to develop a standardized, on-site technique for toxicity assays and a set of standard data for comparisons. The test will not specifically determine whether resistance is or is not a significant problem in the field but will indicate if the test beetles show unusual tolerance to a given chemicei) The test might be used prior to treatment, as an aid to selection of an insecticide. Used post-treatment, this test will help assess possible reasons for lack of control. Colorado potato beetles were collected from the M.S.U. Montcalm Co. Potato Research Farm within 3 weeks of first appearance of summer (non-overwintered) adults and held in the laboratory for 1 week. Trials with some of the insecticides were repeated using 1—3 week old beetles from a laboratory culture originally collected from nightshade in Antrim Co. Tests were run with Furadan, Guthion, Imidan, Monitor, Parathion, Pounce, Pydrin, Sevin, Thiodan, and Vydate. A range of concentrations (usually .001% to 1%) of commercial formulations was prepared for each insecticide. Beetles (in groups of 10) were dipped into the insecticide solution for 1 minute, using a tea strainer. The beetles were then placed on paper towel to remove the excess solution and placed in paper cups with untreated potato foliage as food. The beetles were kept at room temperature and mortality was assessed at 24, 48 and 120 h after treatment. Approximate concentrations required to kill 50% of the beetles (1-day LC50) ranged from 0.004% for Furadan 4F to 1.54% for Monitor (Figure 8). This does not necessarily reflect the relative effectiveness of the insecticides. For example, a material with low contact toxicity, as measured in this test, might have high ingestion toxicity or long residual effectiveness. The data do serve as a basis for assessing tolerance to a particular material. In general, if 5 to 10 times more chemical is required to kill your test beetles than was needed to kill our standard beetles, a significant resistance problem may be present and a different material should be chosen. Also, if even a few of your test beetles survive the very highest doses, resistance may be beginning to show up in the field and a change in material and adoption of other control means such as crop rotation are recommended. If you choose to try this test: (1) Use fresh adults, if possible (overwintered adults will be more susceptible) . (2) Hold beetles at room temperature - 70-75F. Toxicities may vary 5-10x between 60 and 85F. Choice of an alternate material is recommended if: (1) 5-10x concentration is required to kill your beetles compared with the standard results. or (2) Some of your beetles survive even the highest concentration tested. Remember - many factors, including weather, timing, application, and crop stage affect control. Possible resistance is only one factor to be considered. A detailed, step-by-step extension leaflet, including tablespoon/gallon concentrations, will be prepared and distributed through CES offices and published in the Potato Industry News. Table 1. Potato Insecticide Trial Montcalm Research Farm, Entrican MI Rate Treatment Soil treatmentsSoil treatments Temik 15G Temik 15G Temik 15G Lance 20G Lance 20G Lance 20G Thimet 20G + Pay-Off 2.5EC 3 lb ai/A in furrow 3 lb ai/A side dressed 2 lb ai/A side dressed 2.4 oz ai/1000' in furrow 4.8 oz ai/1000' in furrow 2.4 oz ai/1000' in furrow +2.4 oz ai/1000' side dressed 3.5 oz ai/1000' in furrow .1 lb ai/A as needed Code name Soil treatments Temik 3f Temik 3sd Temik 2sd Lance 2.4f Lance 4.8f Lance 2.4fsd Thimet Foliar treatments CME .015 CME .03 RH .06 RH .12 RH .25 UBI .25WP UBI 1.0WP UBI .25EC UBI 1.0EC Lance .5f Baythroid ABG 10g ABG 20g ABG 40g SAN 1pt SAN 2pt SAN 4pt Kryocide Imidan Pounce Untreated Foliar treatmentsFoliar treatments .015 lb ai/A CME-13406 15SC .03 lb ai/A CME-13406 15SC .06 lb ai/A RH-4971 1EC .12 lb ai/A RH-4971 1EC .25 lb ai/A RH-4971 1EC UBI-B3445-1548 50WP .25 lb ai/A UBI-B3445-1548 50WP 1.0 lb ai/A UBI-B5438-1548 6EC .25 lb ai/A UBI-B5438-1548 6EC 1.0 lb ai/A .5 lb ai/A Lance 480 g/1 .05 lb ai/A Baythroid 2EC ABG-6162 ABG-6162 ABG-6162 SAN-410 SAN-410 SAN-410 Kryocide 96WP Imidan 50WP Pounce 3.2EC Untreated 1 pt form/A 2 pt form/A 4 pt form/A 8 lb form/A 1 lb ai/A .1 lb ai/A -- 10 g ai/A (1 pt) 20 g ai/A (2 pt) 40 g ai/A (4 pt) Mean CPB Damage Ratings for the Different Sample Dates Table 2. * Mean Damage Rating: July * Mean Damage Rating: 3 * Mean Damage Rating: July 10 July 17 Mean Mean Damage Rating: * July 24 Mean Damage Rating: * Jul y 31 Damage Rating: * August 8 * Mean Damage Rating: August 14 Soil treatments Temik 3f Temik 3sd Temik 2sd Lance 2.4f Lance 4.8f Lance 2.4fsd Thimet Foliar treatments .25 .00 .13 .00 .00 .13 .13 .38 .38 .00 .25 Foliar treatments .25 .38 .25 . 94 .44 . 25 .63 Foliar treatments .13 .44 .13 .81 .44 .13 .63 Foliar treatments .50 . 63 .50 .75 .56 .31 .56 Foliar treatments .00 .00 .13 .56 .63 .69 .81 .69 .44 . 50 .56 .69 .81 .69 1.25 .44 .69 Foliar treatments Foliar treatments Foliar treatments CME .015 CME .03 RH .06 RH .12 RH .25 UBI .25 WP UBI 1.0 WP UBI .25 EC UBI 1.0 EC Lance .5f Baythroid ABG 1Og ABG 20g ABG 40g SAN 1pt SAN 2pt SAN 4pt Kryocide Imidan Pounce Untreated 1. 13 . 63 .88 .38 .63 1. 13 .75 1.38 1.31 1.63 .63 1.25 1.00 1.00 1.00 1.00 1.00 1.44 .63 1.69 1.50 .63 1.06 .63 . 50 . 38 1.31 1.25 1.56 1.69 1.69 .63 1.88 1.50 1.44 1.25 1.00 1.06 1.56 1.00 1.94 1.88 .88 .81 .56 .81 .25 . 75 .63 .44 .63 .31 .88 .38 .69 .81 .38 1.31 .88 1.06 1.31 .75 .88 .81 .63 .44 .50 1.56 - - - - 1.19 - - - - 1.00 - - - - 1.44 - - - - 1.06 .63 .81 .94 .63 .88 1.25 .94 1.75 1.19 1.00 1.25 .94 .81 1.06 1.94 1.50 1.69 . 69 1.00 1.13 1.31 1.25 1.19 1.44 2.13 1.44 .81 1.00 1.69 1.75 1.06 . 31 1.00 1.00 1.44 1.38 1.19 . 94 1.63 .44 1.81 2.25 .94 .33 1. 19 1.00 .75 1. 19 .81 1.06 1.50 .69 1.56 1.81 1.88 2.25 1.88 2.31 .69 * 0- No damage, 1-slight feeding; leaflets, 2—moderate feeding: leaves, 3—defoliation; stalks left Season long CPB counts Soil and foliar treatments Figure 1. Season long counts averaged over 10 sample dates. Frequency of large larvae by date Figure 2. Number of large larvae per plant during peak larval development. Mean Potato Leafhopper /Plant Figure 3. Mean potato leafhopper per plant averaged over 9 dates. Mean Yield Figure 4. Mean yield per treatments ( lbs/40 row ft) Figure 5. Mean Black Cutworm Adults/ Trap in 1984 Figure 6. Mean Variegated Cutworm Adults/ Trap during 1984 Figure 7. Mean European Corn Borer Adults/ Trap in 1984 Figure 8. 1984 NEMATOLOGY RESEARCH G.W. Bird, Nematologist Department of Entomology In 1984 potato microplot experiments were conducted to evaluate the joint influence of Pratylenchus penetrans and Verticillum dahliae on the growth and yield of Superior and Atlantic potatoes in relation to the early-die disease complex. Although root-lesion nematode population densities increased, they had no significant impact on tuber yields. The results of the early-die index were inconclusive (Table 1). It is highly probable that the seed pieces of both varieties were a source of V. dahliae infection. Twenty potato varieties were evaluated for susceptibility to the early-die disease complex and the root-lesion nematode (P. penetrans). The results could be divided into three groups of varieties based on nematode reproduction and tuber yield in the absence of a nematicide, compared to the yield in the presence of a nematicide. Seven of the varieties were relatively tolerant to the early-die disease complex (Table 2), and similar to Russett Burbank in response. Three were very susceptible, and similar to Superior. Eight varieties were intermediate in their susceptibility to the early-die disease complex. In Range 3 at the Montcalm Potato Research Farm, tuber yield increases resulting from the control of the root-lesion nematode were almost as great with Mocap applied on a broadcast basis as with Temik applied on an in-furrow basis (Table 3). This experiment was irrigated throughout the growing season. It appears that Mocap can be a substitute for Temik for root-lesion nematode control in Michigan potato production. The in-furrow treatment of Mocap, however, was not satisfactory. Dry land potatoes were grown at the Montcalm Potato Research Farm in 1984 in Ranges 11 and 12. The yields were greater than anticipated (Tables 4 & 5). Ranges 11 & 12 had not been planted with potatoes for approximately ten years. Although the nematicides evaluated provided control of P. penetrans, there were no potato tuber yield responses. During the past 11 years, the Michigan State University Nematology Program has completed 29 potato nematicide research trials. These were conducted with five different varieties. Yield increases associated with the combination of Temik and Vorlex averaged 120 cwt greater than the nontreated controls (Table 6). Temik is the only nematicide that provide season long control of P. penetrans. populations. Profit increases associated with these trials ranged from $172 per acre for Temik, to $520 per acre for the combined application of Temik and Vorlex (Table 7). Although Vapan was not included in these trials, it is estimated that the profit increase associated with this pesticide would be approximately $290 per acre. Table 1. Influence of Pratylenchus penetrans and Verticillium dahliae on Superior and Atlantic tuber production in microtiles. Pi (Variety) Pf - Tuber Yield (lbs) Tuber Yield (lbs) - Index +Index - Tubers (no.) + Tubers (no.) - Tuber Size (lbs) Tuber Size (lbs) - + 0 Superior 0 Atlantic 10 Superior 10 Atlantic 100 Superior Pf + 0a la 0a la 16b 44b 37b 82b 38b 67b + 1.7a 1.8a 2.3a 1.8a 1.9a 1.7a 2.4a 1.6a 1.8a 2.2a 4.3cd 4.0cd 1.7abc 0.7a 4.3cd 3.6bcd 9a 8c 11ab 9a 8a 12ab 0.19ab 0.27b 0.21ab 0.24ab 0.35b 0.14a 1.6abc 2.1 abcd 9a 10ab 0.29b 0.27b 4.6d 3.4 bcd 15b 9a 0.16a 0.16a 100 Atlantic 71b 103b 1.8a 2.1a 2.1 abcd 1.3ab 12ab 8a 0.18ab 0.26b Table 2. 1984 potato early-die disease complex variety microplot trial 1. Group I (Russet Burbank) Islander Oceania Simcoe 702-91 704-1 (7 crossed out) 0(h andwritten) 002-171 G670-11 Group II (Onaway/Katahdin/Onaway/Denali) Snowchip Conestoga Island Chipper 714-10 Group III (Superior) Chipbelle Tukon 701-22 1 Groups based on one-year of microplot observations. Rankings not to be used as commercial recommendations. Table 3. Influence of nematicides on root-lesion nematode control and Superior tuber yields. Treatment (rate of method) Root-lesion nematodes Root-lesion nematodes Root-lesion nematodes 8/31 8/8 5/16 Tuber Yield (cwt.) Total Tuber Yield (cwt.) Tuber Yield (cwt.) A J Tuber Yield (cwt.) B Check Mocap 6EC 6.0 lb-B Mocap 6EC 9.0 lb-B Mocap 6EC 12.0 lb-B Mocap 15G 3.0 lb-IF Temik 15G 3.0 lb-IF AR 150867 1.0 lb-6B AR 15086 2.0 lb-6B F 3843 2.0 lb-AP F 3843 4.0 lb-AP 5a 4a 2a 5a 7a 5a 3a 7a 4a 4a 50ab 12a 9a 7 a 44ab 2a 16ab 22ab 64b 63b 74b 64ab 42ab 6lab 79b 5a 28ab 26ab 65ab 58ab 306a 332ab 361bc 373bc 319ab 405c 297a 365bc 322ab 297a 262ab 290abc 313bcd 328cd 275abc 345d 251a 317bcd 280abc 260ab 9ab 9ab llab 6a 13ab 30c 20bc 19abc llab 8ab 30ab 32bc 37cd 39d 30ab 31ab 25a 28a 30ab 28ab Table 4. Montcalm potato nematicide trial. Treatment, Rate (ai/A) and Application Check Temik 15G, 3.0 in furrow F 3843, 12.0 14 days preplant F3843, 4.0 14 days preplant F 3843, 2.0 14 days preplant F 3843, 12.0 7 days preplant F 3843, 4.0 7 days preplant F 3843, 2.0 7 days preplant F 3843, 12.0 at planting Vorlex 10 gal/A broadcast Pre-treatment Soil (5/1/84) Pratylenchus penetransMidseason Pratylenchus Pratylenchus penetrans penetrans Midseason Soil(8/8/84) Roots (8/8/84) (8/8/84) Pratylenchus penetrans Midseason Soil+Roots 2a 3a 2a 2a 4a 3a 6a 5a 4a 2a lOab 0a 14ab 5ab 5ab 13ab 14ab 17b 12ab la 51a 8a 63ab 8a 108a 124b 60a 59a 45a 69a 77a 73a 34a 65ab 64ab 59ab 83ab 94ab 85ab 36ab Pratylenchus penetrans Harvest Soil (8/31/84) 14ab la l0ab 19b 13ab 8ab llab l0ab 12ab 4ab Yield (cwt.) A Yield (cwt.) B Yield (cwt.) Jumbo Yield (cwt.) Total 248a 226a 22a 25ab 15a 8a 228a 31b 231a 29ab 5a 8a 285a 259a 264a 268a Specific Gravity 1.078a 1.080a 1.076a 1.078a 240a 28ab 12a 280a 1.079a 229a 25ab 233a 25ab 259a 26ab 213a 28ab 8a 9a 5a 6a 262a 267a 280a 253a 1.079a 1.078a 1.078a 1.080a 276a 24ab 15a 320a 1.081a Yield (cwt.) Pratylenchus penetrans Spec. Yield (cwt.) Total Gravity Pretreatment (5/1/84) Pratylenchus penetrans Pratylenchus penetrans Roots Soil(8/8/84) (8/8/84) Pratylenchus penetransSoil+Roots (8/8/84) Harvest Pratylenchus penetrans (8/29/84) Table 5. 1980 potato nematicide trial. empty table cell Disyston Check Temik 15G, 3.0 Temik 15G, 3.0 Vorlex 1.0 g/A Vorlex + Disyston SN556 10 g + Disyston SN556 15g + Disyston SN556 10g + Temik SN556 15g + Temik Soilex 10g + Disyston Yield (cwt.) Yield (cwt.) A B 273a 294a 290a 257a 280a 280a 260a 206a 260a 31a 29a 32a 29a 32a 35a 32a 34a 29a J 15a 12a 26a 15a 12a 9a 15a 17a 1la 319a 335a 348a 303a 324a 324a 307a 357a 300a 1.080a 1.079a 1.081a 1.082a 1.082a 1.081a 1.082a 1.079a 1.080a 4a 2a la la 0.4a 4a 2a 2a 2a 3a 0a 0a la 2a 0.2a 0a 0a 3a 22a la 0a la 8a la 0a 0.2a 9 24a lb 0a 2b l0ab lb 0b 0.2b 12ab 20a 0.4b 0b 2b 0.8b 0.2b 0b 0b 6b Table 6. Summary of 29 Potato nematicide trials conducted at the Michigan State University Montcalm Potato Research Farm from 1974-1984. Tuber yield (cwt/A) Tuber yield (cwt/A) Pratylenchus penetrans/100cm3 soil Pratylenchus penetrans/100cm3 Pratylenchus penetrans/100cm3 soil and 1.0g root (Pm) and 1.0g root Pratylenchus penetrans/100cm3 soil and 1.0g root Tuber yield (cwt/A) Check Temik Vorlex Tuber yield (cwt/A) Temik & Vorlex Check (Pm) Temik (Pm)Vorlex soil and 1.0g root (Pm) Temik & Vorlex 95 118 57 91 131 104 9 21 1 2 40 16 27 69 1 42 42 47 13 1 -- -- -- 8 Variety (No. expts.) Russet Burbank (7) Superior (15) Atlantic (4) Onaway (2) Monona (1) 275 229 382 169 187 295 284 410 199 209 379 367 --- --- 368 312 470 206 180 --- Mean (29) 254 291 337 374 Table 7. Influence on potato production system profit based on 29 experiments between 1974 and 1984). Nematicide Cost/A Yield Increase/A Profit Increase/A 1 Temik Vorlex Temik + Vorlex Vapam 2 $ 50 150 200 250 37 cwt 83 cwt 120 cwt 90 cwt $ 172 348 520 290 1 Based on a gross return of $6/cwt. 2 Expert opinion (Vapam estimates not based on research data). THE INFLUENCE OF FOLIAR FERTILIZERS AND A SOIL FUMIGANT ON PLANT NUTRITION, YIELD AND TUBER QUALITY OF POTATOES M.L. Vitosh, G.W. Bird, R. Leep, R. Hammerschmidt, R.W. Chase and E. Grafius Department of Crop and Soil Sciences, Entomology and Botany and Plant Pathology The objectives of these studies were to evaluate the effects of foliar fertilizer and a soil fumigant on potato plant nutrition, disease control, tuber yield and quality. Two studies were conducted. One at the Montcalm Research Farm and another on the John Verbrigghe farm in Delta county in the Upper Peninsula. The experiment at the Montcalm Research Farm was conducted on two potato varieties, Atlantic and Superior with and without Vorlex, a soil fumigant. The experiment in the Upper Peninsula was conducted only on the Superior variety without the soil fumigant treatment. The foliar fertilizer treatments were the same at both locations. Treatment two was a 2% nitrogen solution made from urea. Treatment three was a 2% nitrogen, phosphate and potash solution made from a water soluble 20-20-20 fertilizer. Both materials were applied in 12.3 gallons of water per acre, 5 times during the growing season, suppling a total of 10 lb of N in the case of the urea treatment and 10 lbs of N, P2O5, and K2O in the case of the N-P-K treatment. At the Montcalm Research farm, Vorlex was applied 8-10 inches below the soil surface as a broadcast rate of 10 gallons per acre on May 1st. Other cultural and management practices for the two studies are shown in Table 1. Tuber Yield, Quality and Economic Analysis Montcalm Study Tuber yield, quality and economic analysis data for the Montcalm study are shown in Table 2. The Atlantic variety produced significantly higher total yields, U.S. No. 1’s and large size tubers (those over 3 1/4 inches), than Superior. Vorlex significantly increased yields in all size categories measured. Neither the N or the N-P-K foliar fertilizer treatments had any affect on yields. Tuber specific gravity was considerably higher for the Atlantic variety, but was reduced slightly by the soil fumigant. A similar type of response was observed with Atlantic’s in 1982, however, the negative response does not appear to be large enough to be of great concern in light of the increased yields for the soil fumigant. Detailed observations of the tubers did not show any significant amount of hollow heart, internal browning, or scab which could be associated with the treatments. Estimates of plant foliage and ground cover on August 10th showed that there was slightly more foliage associated with the soil fumigant treatment and considerable more foliage associated with the Atlantic variety. The foliar fertilizer treatments did not exhibit any improved growth, color or cover at this time. The economic analysis indicates that tuber size and yield are the important factors in determining net income. Greater net income (income after subtracting the cost of the treatments in this study) was associated with the Atlantic variety and the soil fumigant even though this treatment was prorated at a cost of $120 per acre. Net income was not significantly affected by the foliar fertilizer treatments. Upper Peninsula Study The effects of the two foliar fertilizer treatments upon tuber yield and specific gravity for the study in Delta county are presented in Table 3. Potato yield and size were not significantly affected by the foliar treatments. Specific gravity was significantly lower with the N foliar treatment when compared to the other treatments. Montcalm Study Foliar Disease Ratings Observations on the development of foliar disease symptoms were made at four times during the growing season. Early blight (Alternaria solani) was the primary focus of these observations due to the relationship between this disease and general plant health. Disease symptoms were first recorded at a significant level on July 3 and July 17 for the Superior and Atlantic varieties, respectively. Among the foliar fertilizer treatments, a significant decrease in disease symptoms was found with the N-P-K treatment as compared to both the N and no foliar fertilizer treatments on July 17 and August 1 for Atlantic plots receiving no soil fumigant and on July 17 and August 1 and 10 for Atlantics receiving Vorlex. No foliar fertilizer effect was observed with Superior. In addition, Vorlex treated Atlantic’s exhibited a significantly lower level of disease as compared to non-fumigated Atlantic plots on August 1 and 10. This relationship was also found for Superiors on July 3 and 17 and August 11. Atlantics exhibited less disease than Superior at all dates. This is probably due to differences in varietal maturity. The disease ratings for this study are presented in Table 4. Upper Peninsula Study Early blight ratings made on August 20 indicated little difference between the treatments. Total leaf area affected in all treatments was 40 to 44 percent. Montcalm Study Insect Activity All plots of this experiment were monitored for insects periodically throughout the growing season. The plant density of Colorado Potato Beetle, Potato Leafhopper (PLH) and Aphid is presented graphically in Figures 1-4. All levels are considered to be low and plant damage was minimal. All plots were sprayed with insecticides according to the regular schedule established for the research farm. Nutrient Analysis of Potato Petioles Montcalm Study Potato petioles were sampled 5 times during the growing season just prior to the application of the foliar fertilizers. Replications 1 and 4, 2 and 5, and 3 and 6 were combined after sampling to reduce the cost of the nutrient analysis. The samples were oven dried, ground and sent to The Ohio State University plant analysis laboratory for nutrient analysis. The data for the Montcalm location are shown in Tables 5-9. The overall nutrient mean values shown at the bottom of the tables can be seen in most cases to decline steadily throughout the season, particularly nitrate-nitrogen (NO3-N) and potassium (K). The exceptions are calcium (Ca) and magnesium (Mg) which are usually balanced by K uptake. As the K concentration decreased throughout the season, the Ca and Mg concentration increased. The nitrate nitrogen levels for both varieties dropped below 10,000 ppm some time between July 12 and July 23. The 10,000 ppm level has often been used as the critical level at which time the addition of nitrogen fertilizer would have been expected to give a yield increase. Two of the five foliar applications were applied after the nitrate level was below 10,000 ppm, but no response in yield or increase in nitrate content of the petioles was observed. We would conclude that the amount of N that can be added in foliar applications is insufficient to have any affect on the plant and the enhancement of yield. The plant requirements on a daily basis are estimated to be greater than the amount supplied in any one foliar treatment which was applied approximately every 10 days. Vorlex initially had a negative affect on the level of nitrate nitrogen in the petioles but on July 12 the response was positive. No significant differences in nitrate levels were found at the other sampling dates. Vorlex had a positive affect on phosphorus uptake in 3 out of the 5 sampling dates. Calcium levels were found to be significantly lower at all of the sampling dates. Much of the decrease can be explained by the increase in K uptake and the balancing affect described earlier, however, the K content was found to be significant only on the last sampling date. Vorlex significantly reduced the uptake of manganese (Mn) at all sampling dates. In all previous studies we have observed this depressing affect of Vorlex, but we still do not fully understand why this is occurring and whether it has any significant relationship to the yield increases observed. The foliar fertilizer treatments in general did not affect the nutrient composition of the potato petioles. On June 20, before any foliar treatments were applied, the zinc (Zn) content was found to be significantly higher in those plots which were to receive the N foliar applications. On August 2 the Mg content was found to be significantly lower in these same plots. It is doubtful that either of these significant differences have any agronomic implications and must be considered to be due to field and sample variation. Upper Peninsula Study Potato petioles at this site were sampled in the same manner as those at the Montcalm location except that all 4 replications were used for the analysis. The data for this study are presented in Table 10. Although the soil phosphorus level at this site is considered high, analysis of the petioles indicated very low levels throughout the growing season. At the present time we do not have an explanation for the extremely low values. The two foliar fertilizer treatments, however, did result in increased P concentrations of potato petioles at the July 18 and August 9 sampling dates. Analysis for all other nutrients appear to be normal but were unaffected by the foliar fertilizer treatments. Nitrate nitrogen levels appeared to stay well above the 10,000 ppm critical level throughout the growing season. Again, we would conclude that foliar fertilizer treatments such as these do not add enough nutrients to significantly affect the nutrient composition of the plant or yield and would discredit certain claims of greater efficiency for foliar applied nutrients. Montcalm Study Nematode Evaluations Pre-plant application of Vorlex broadcast at 10 gallons per acre resulted in a significant increase in tuber yields of both Superior and Atlantic potatoes. Although the application of Vorlex did not result in statistically significant lower root-lesion nematode population densities for the individual foliar nutrient treatments (Table 11), the Vorlex treatment resulted in a significant decrease in the combined soil and root populations of Pratylenchus penetrans (root-lesion nematode) on August 7, 1984, compared to the nontreated control plots (Table 12). This decrease, however, was not reflected in the final population densities of P. penetrans on September 20, 1984. The potato varieties did not have a significant (P = 0.05) impact on the population dynamics of P. penetrans. The population density of P. penetrans on August 7, 1984, however, was significantly greater in the plots receiving foliar application of N or N-P-K than in the nontreated controls. Table 1. 1984 cultural and management practices for the Montcalm and Upper Peninsula studies. Montcalm Study Soil type: McBride sandy loam Previous crop: Rye cover Plowdown potash: 250 lb/acre Soil fumigant: 10 gal/acre applied May 1 Planted: May 10, 1984 Row spacing: 34 inches Seed spacing: 10 inches Starter fertilizer: 750 lb 10-20-20 per acre Soil applied insecticide: 3 lb a.i./acre Disyston Herbicide: Dual at 2 lb/acre + Lexone 4L at .5 lb/acre pre-emergence Sidedress nitrogen: 110 lb N/acre May 31 Foliar application dates: June 21, July 2, 13, 23, and August 3 Foliar application rate: 12 gallons of solution per acre Harvested: September 19 and 20, 1984 Rainfall: 5.1, 2.9, 3.8, and 2.0 inches for May-August, respectively Irrigation: 12 inches total for the season Soil test information sampled May 10, 1984: pH - 5.6 Bray Pl = 621 lb/acre Exch. K = 294 lb/acre Exch. Ca = 680 lb/acre Exch. Mg = 128 lb/acre Upper Peninsula Study Soil type: Onaway loam Planted: May 24, 1984 Starter fertilizer: 750 lb 10-20-20 per acre Sidedress nitrogen: 100 lb N/acre July 7 Foliar application dates: July 7, 18, 30, August 9, and 20 Foliar application rate: 23 gallons of solution per acre Harvested: October 2, 1984 Soil test information: pH = 6.8 Bray Pl = 272 lb/acre Exch. K = 224 lb/acre Table 2. Potato tuber yield, quality, plant growth and net income as affected by variety, soil fumigant and foliar fertilizers. Treatments 1 Foliar Fertilize Tuber Yield and QualityU.S. No. 1cwt/A Tuber Tuber Yield and Quality Over 3 1/4"cwt/A Yield and Quality Under 1 7/8"cwt/A None N N-P-K None N N-P-K 40 41 35 66 61 55 411 413 397 449 449 456 23 26 25 29 28 31 Tuber Yield and Quality Specific Gravity —g/cc— 1.090 1.092 1.092 1.088 1.090 1.090 Tuber Yield and Quality Total Yieldcwt/A 434 439 422 478 477 486 Tuber Yield and Quality Net 3 Income$/A Tuber Yield and Quality Net Income 4 Over Check $/A 2,835 2,856 2,704 3,025 3,017 3,022 695 680 528 849 841 846 rating 5 0.3 0.8 0.3 0.2 0.2 0.3 0.2 0.0 0.2 0.2 0.2 0.3 0.2 0.5 0.2 0.2 0.0 0.3 0.2 0.3 0.2 0.2 0.0 0.3 8.3 8.5 8.2 8.3 8.7 8.7 Tuber Yield and Quality Hollow Heart Internal Tuber Yield and Quality Surface Tuber Yield and Quality Browning Scab rating 5 % 7 Pitted Tuber Yield and Quality Plant Tuber Yield and Quality Scab Foliage rating 6 rating 8 Treatments 1 Soil Fumigant None None None Vorlex Vorlex Vorlex None None None Vorlex Vorlex Vorlex Variety Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Superior Superior Superior Superior Superior Superior Overall Means 2 19 31 24 34 37 29 None N N-P-K None N N-P-K 318 335 339 374 373 362 Overall Means 2Overall Means 2 empty table cell50 b empty table cell29 a empty table cell32 a empty table cell47 b empty table cell40 empty table cell43 empty table cell36 25 24 25 29 28 26 343 359 364 403 401 388 Overall Means 2 1.075 1.073 1.075 1.073 1.074 1.072 Overall Means 2 0 2,176 134 2,310 119 2,295 2,466 290 2,459 283 167 2,343 Overall Means 2 Overall Means 2 0.5 0.5 0.2 0.2 0.2 0.7 Overall Means 2Overall Means 2 0.0 0.0 0.0 0.0 0.2 0.2 Overall Means 2 0.3 0.0 0.0 0.0 0.2 0.0 Overall Means 2 0.0 4.2 0.0 4.2 0.0 3.8 0.0 5.0 0.2 5.0 0.2 4.8 Overall Means 2 Overall Means 2 Overall Means 2 Atlantic Superior 569 b 0 a 0 a 193 b 456 b 376 a 394 a 439 b 414 419 415 2,980 b 2,412 a 2,540 a 2,853 b 2,685 2,723 2,681 1.090 b 1.074 a 1.083 b 1.081 a 1.081 1.082 1.082 429b 27 350a 26 369a 25 a 410b 28 b 388 393 388 Overall Means 2 8.4 b Variety Variety 4.5 a 6.2 a None Fumigant Fumigant 6.7 b Vorlex 6.3 Foliar FertilizerNone 6.6 N Foliar Fertilizer Foliar FertilizerN-P-K 6.4 1 Foliar N was applied in 5 applications as urea in 5 gallons of water to supply 2 lb N/A in each application. Foliar N-P-K was applied in 5 applications as a 20-20-20 foliar fertilizer in 5 gallons of water to supply 2 lb N, P2O5, and K2O/A in each application. 2 Any two treatment means followed by different letters are significantly different (p = .05). 3 Net income after expenses: N @ $.20/lb, Foliar N-P-K @ $.60/lb, Vorlex @ $120/A, Tubers over 3 1/4” @ $8.65, Tubers 2-3 1/4” @ $6.65, and Tubers under 2” @ $1.00. 4 Check = Superior, no fumigant and no foliar fertilizer. 5 Ratings of 0-5, where 0 = no incidence and 5 = high incidence. 6 Ratings of 0-10, where 0 = no incidence and 10 = high incidence. 7 Percent of surface covered with scab. 0.2 0.1 0.1 0.1 0.1 0.2 0.2 0.2 0.1 0.1 0.1 0.1 0.1 0.2 0.2 0.1 0.1 0.1 0.2 0.1 0.1 0.4 0.4 0.4 0.3 0.3 0.4 0.4 0 65 -34 27 27 27 8 Ratings of 0-10, where 0 = no ground cover and 10 = complete ground cover as measured on August 10. Table 3. Potato tuber yield, quality, plant growth and net income as affected by foliar fertilizers (Upper Peninsula). Treatments 1 Variety Foliar Fertilize Tuber Tuber Yield and Tuber Yield and Tuber Yield and Quality Economics Economics Over Tuber Yield and Quality 3 1/4"cwt/A and Quality Yield Quality Under 1 Quality Tota l Yield cwt/A Specific Gravity Plant Tuber Yield and Quality Foliage Net 3 Income$/A Net Income 4 Over Check U.S. No. 1 cwt/A 7/8" cwt/A —g/cc— rating 2 $/A Superior Superior Superior None N N-P-K 45 26 32 321 342 321 28 37 36 349 379 357 1.076 1.072 1.076 44 44 40 2,524 2,534 2,441 0 10 -83 None of the treatment means are significantly different (p = .05). 1 Foliar N was applied in 5 applications as urea and supplied 2 lb N/A in each application. Foliar N-P-K was applied in 5 applications as 20-20-20 foliar fertilizer and supplied 2 lb N, P2O5 and K2O/A in each application. 2 Total percent leaf area as observed on August 20. 3 New income after expenses: N @ $.20/lb, Foliar N-P-K @ $.60/lb, Tubers over 3 1/4" @ $8.65, Tubers 2-3 1/4" @ $6.65, and Tubers under 2" @ $1.00. 4 Check = No foliar fertilizer. Table 4. Foliar disease ratings taken periodically throughout the growing season (Montcalm Study). Treatments 1 Disease Rating 1 Disease Rating 1 Variety Soil Fumigant Foliar Treatments 1 Fertilize Disease Rating 1 July 3 July 17 August 1 August Disease Rating 1 10 Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Superior Superior Superior Superior Superior Superior None None None Vorlex Vorlex Vorlex None None None Vorlex Vorlex Vorlex None N N-P-K None N N-P-K None N N-P-K None N N-P-K 1.01 1.03 1.00 1.01 1.00 1.00 1.33 1.32 1.42 1.21 1.25 1.24 1.21 1.18 1.05 1.25 1.20 1.00 2.10 2.20 2.18 1.75 1.60 1.63 1.66 1.66 1.25 1.58 1.50 1.00 3.83 3.00 3.17 2.92 2.17 2.50 2.02 2.10 1.75 1.79 1.78 1.23 4.12 3.87 3.77 3.56 3.43 3.22 1 = 0-5% lesion coverage 1 2 = 6-10% lesion coverage 3 = 11-25% lesion coverage 4 = 26-50% lesion coverage 5 = over 50% lesion coverage Figure 1. Egg masses of Colorado Potato Beetle per plant throughout the growing season Figure 2. Larvae of Colorado Potato Beetle per plant throughout the growing season. Figure 3. Colorado Potato Beetle Adults per plant throughout the growing season. Figure 4. Aphids and Potato Leaf Hoppers per plant throughout the growing season. Table 5. Elemental composition on potato petioles as affected by variety, soil fumigant and the application of foliar fertilizers. Treatments 1 Foliar Fertilizer Treatments 1 Soil Fumigant None None None Vorlex Vorlex Vorlex None None None Vorlex Vorlex Vorlex Variety Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Superior Superior Superior Superior Superior Superior None N N-P-K None N N-P-K None N N-P-K None N N-P-K % Elemental Content of potato Petioles 3K Elemental Content of potato Petioles 3M P % Elemental Content of potato Petioles 3 Elemental Content Elemental Content of potato Petioles of n ppm 3 Mg % potato Petioles 3 Ca % Elemental Content of potato Petioles 3 N03-N -ppm— 24,433 20,560 22,833 21,767 21,067 21,033 26,667 25,333 25,860 23,500 24,000 22,833 0.57 0.57 0.56 0.47 0.48 0.47 0.59 0.59 0.67 0.49 0.54 0.46 Overall Means 2 0.30 0.31 0.30 0.29 0.30 0.31 0.28 0.28 0.32 0.29 0.29 0.27 Overall Means 2 Overall Means 2 13.46 13.35 13.39 13.53 13.24 13.56 12.05 12.32 13.15 12.14 12.47 11.90 0.68 0.68 0.66 0.72 0.76 0.77 0.56 0.60 0.61 0.66 0.67 0.66 278 260 268 129 129 140 242 289 281 89 126 106 Overall Means 2 Elemental Content of potato Petioles 3 Fe ppm Elemental Elemental Content of potato Petioles 3Cu ppm Elemental Content of potato Petioles 3Zn ppm Content of potato Petioles 3B ppm 35 37 35 36 35 37 33 34 35 35 34 33 222 25 421 33 21 213 184 24 27 269 28 258 30 324 28 371 30 366 31 379 39 475 400 35 Overall Means 2 Overall Means 2 105 108 97 109 110 108 98 133 126 113 134 113 Overall Means 2 Overall Means 2 Overall Means 2Overall Means 2 Overall Means 2 Means 2 Overall Means 2 Variety Variety Fumigant Fumigant Foliar FertilizerNone Foliar Fertilizer Foliar FertilizerN-P-K Overall Atlantic empty table cell21,949 a Superior empty table cell24,699 b empty table cell24,281 b None empty table cell22,367 a Vorlex empty table cell24,092 empty table cell22,740 empty table cell23,140 N 0.71 b 0.63 a 0.63 0.71 0.65 0.68 0.67 13.42 b 12.34 a 12.95 12.81 12.79 12.85 13.00 0.52 a 0.56 b 0.59 b 0.49 a 0.53 0.54 0.54 0.30 0.29 0.30 0.29 0.29 0.30 0.30 201 189 270 b 120 a 185 201 199 261 a 386 b 320 328 277 a 384 b 309 a 36 b 34 a 35 35 35 35 35 26 a 32 b 28 31 28 32 28 106 a 119 b 111 114 106 a 121 b 111 a 1 Foliar N was applied in 5 applications as urea in 5 gallons of water to supply 2 lb N/A in each application. Foliar N-P-K was applied in 5 applications as a 20-20-20 foliar fertilizer in 5 gallons of water to supply 2 lb N, P2O5, and K2O/A in each application. 2 Any two treatment means followed by different letters are significantly different (p = .05). 3 Sampled on June 20. Table 6. Elemental composition on potato petioles as affected by variety, soil fumigant and the application of foliar fertilizers. Treatments 1 Soil Fumigant 1Foliar Treatments Fertilizer Elemental Content of potato Petioles 3K Elemental Content Elemental Content of potato Petioles Elemental Content of potato Petioles 3M Elemental Content of potato Petioles 3 Fe Variety Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Superior Superior Superior Superior Superior Superior Overall Means 2 Variety Variety None None None Vorlex Vorlex Vorlex None None None Vorlex Vorlex Vorlex Overall Means 2 Elemental Content of potato Petioles 3 P % % of 3 Mg % 0.43 0.49 0.48 0.53 0.52 0.54 0.48 0.48 0.49 0.51 0.56 0.50 None N N-P-K None N N-P-K None N N-P-K None N N-P-K 0.33 0.37 0.36 0.33 0.34 0.36 0.37 0.35 0.37 0.36 0.37 0.32 Overall Means 2 NO3-N Elemental Content of potato Petioles 3 ppm 14,667 14,167 13,000 15,000 15,167 13,833 17,333 17,000 17,167 19,167 17,333 18,333 potato Petioles 3 Ca % 0.62 0.67 0.66 0.58 0.57 0.59 0.77 0.71 0.74 0.65 0.64 0.60 Overall Means 2 12.70 13.74 13.09 14.19 14.18 13.83 14.37 14.32 14.14 13.96 13.98 13.50 Overall Means 2Overall Means 2Overall Means 2 empty table cell14,306 a empty table cell17,722 b empty table cell15,556 empty table cell16,472 empty table cell16,542 empty table cell15,917 empty table cell15,583 13.62 14.04 13.72 13.94 13.80 14.05 13.64 0.35 0.36 0.36 0.35 0.35 0.36 0.35 Atlantic Superior Fumigant Fumigant 63 68 None 62 a Vorlex 70 b None Foliar Fertilizer 64 N Foliar Fertilizer 68 Foliar FertilizerN-P-K 65 1 Foliar N was applied in 5 applications as urea in 5 gallons of water to supply 2 lb N/A in each application. Foliar N-P-K was applied in 5 applications as a 20-20-20 foliar fertilizer in 5 gallons of water to supply 2 lb N, P2O5, and K2O/A in each application. 2 Any two treatment means followed by different letters are significantly different (p = .05). 3 Sampled on July 2. 0.62 a 0.68 b 0.69 b 0.61 a 0.66 0.65 0.65 0.50 0.50 0.47 a 0.53 b 0.49 0.51 0.50 101 a 121 b 112 111 110 a 114 b 110 a 257 b 210 a 298 b 169 a 224 231 245 36 a 39 b 38 37 37 ab 38 b 36 a 14 a 19 b 16 17 16 17 16 n ppm 297 288 329 200 202 223 275 306 291 125 128 137 ppm Elemental Elemental Content of potato Petioles 3Cu ppm Elemental Content of potato Petioles 3Zn ppm Content of potato Petioles 3B ppm 96 109 109 101 95 98 120 126 112 122 127 121 Overall Means 2 34 38 35 36 36 36 40 40 38 38 39 36 Overall Means 2 13 15 13 15 13 14 17 18 17 19 21 21 58 61 56 71 68 64 58 69 67 69 74 71 Overall Means 2 Overall Means 2 Overall Means 2 Overall Means 2 Table 7. Elemental composition on potato petioles as affected by variety, soil fumigant and the application of foliar fertilizers. Elemental Content of Potato Petioles 3 Elemental Content Elemental Content of Potato Petioles 3 Elemental Content of Potato Petioles 3 Mn Elemental Content of Potato Petioles 3 Treatments 1 Soil Fumigant None None None Vorlex Vorlex Vorlex Variety Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic None Vorlex Vorlex Vorlex None None Superior Superior Superior Superior Superior Superior Overall Means 2Overall Variety Variety Means 2 Atlantic Superior Fumigant Fumigant None Vorlex None Foliar Fertilizer N Fertilizer Foliar Foliar FertilizerN-P-K Treatments 1 Foliar Fertilizer K Mg % % Potato Petioles 3 Ca % ppm Elemental Content of Potato Petioles 3 P % of 0.38 0.41 0.40 0.35 0.38 0.40 0.31 0.31 0.30 0.33 0.29 0.31 Overall Means 2 289 265 290 191 216 224 241 232 236 158 138 199 Overall Means 2 None N N-P-K None N N-P-K None N N-P-K None N N-P-K NO3-N Elemental Content of Potato Petioles 3 -ppm— 11,583 11,500 11,750 12,417 12,083 14,750 16,167 14,917 14,333 17,500 17,417 16,333 0.64 0.71 0.70 0.55 0.57 0.62 0.73 0.65 0.68 0.63 0.56 0.63 Overall Means 2 11.21 0.47 11.26 0.43 0.42 11.14 0.54 12.09 0.50 11.53 0.45 11.85 0.38 11.54 0.42 11.69 11.24 0.44 11.39 0.51 0.55 11.65 11.82 0.49 Overall Means 2Overall Means 2 Overall Means 2 empty table cell12,347 a empty table cell16,111 b empty table cell13,375 a empty table cell15,083 b empty table cell14,417 empty table cell13,979 empty table cell14,292 0.47 0.47 0.43 a 0.51 b 0.47 0.48 0.45 11.51 11.56 11.35 11.72 11.56 11.53 11.51 Zn ppm Elemental Content of Potato Petioles 3 Fe ppm Elemental Content of Potato Petioles 3 Cu ppm Elemental Content of Potato Petioles 3 B ppm 36 37 37 35 34 41 36 51 33 55 32 40 40 33 32 41 37 33 33 43 34 57 35 53 Overall Means 2 10 69 9 63 12 74 68 13 10 63 11 66 70 12 74 12 13 83 77 15 17 87 116 19 Overall Means 2 Overall Means 2 Overall Means 2 Overall Means 2 0.63 0.65 0.68 b 0.59 a 0.64 0.62 0.65 0.39 b 0.31 a 0.35 0.34 0.34 0.35 0.35 246 b 201 a 259 b 188 a 220 212 237 67 84 72 79 71 72 85 34 33 34 34 34 33 34 11 a 15 b 11 14 13 12 14 43 45 39 a 50 b 43 47 43 1 Foliar N was applied in 5 applications as urea in 5 gallons of water to supply 2 lb N/A in each application. Foliar N-P-K was applied in 5 applications as a 20-20-20 foliar fertilizer in 5 gallons of water to supply 2 lb N, P2O5 and K2O/A in each application. 2 Any two treatment means followed by different letters are significantly different (p = .05). 3 Sampled on July 12. Table 8. Elemental composition on potato petioles as affected by variety, soil fumigant and the application of foliar fertilizers. Elemental Elemental Content of Potato Petioles 3 Elemental Content of Potato Elemental Content of Potato Petioles 3Mn Elemental Content of Potato Petioles 3 Treatments 1 Soil Fumigant None Treatments 1 Foliar Fertilizer Content of Potato Petioles 3Fe ppm Elemental Elemental Content of Potato Petioles 3Cu ppm Elemental Content of Potato Petioles 3Zn ppm Content of Potato Petioles 3B ppm 34 34 34 33 33 33 34 34 34 34 33 35 51 55 54 47 55 56 58 51 52 54 54 57 Overall Means 2 27 28 28 34 31 26 20 20 18 22 25 27 Overall Means 2 Overall Means 2 Overall Means 2 6 6 6 5 6 6 5 4 4 4 5 6 K % Ca % Petioles 3 Mg % Variety Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic None None Vorlex Vorlex Vorlex Elemental Content of Potato Petioles 3 P % ppm 0.18 0.19 0.19 0.23 0.23 0.23 None 0.17 None 0.18 None 0.17 Vorlex 0.22 Vorlex 0.21 Vorlex 0.21 Overall Means 2 Overall Means 2Overall Means 2 Elemental Content of Potato Petioles 3 N03-N -ppm- 4,917 4,775 4,808 4,092 4,142 4,233 6,108 7,733 6,833 8,125 6,250 7,500 0.72 0.92 0.72 0.93 0.92 0.74 0.78 0.64 0.76 0.65 0.68 0.79 0.99 0.53 0.90 0.47 0.92 0.47 0.81 0.45 0.80 0.44 0.44 0.78 Overall Means 2 Overall Means 2 8.96 9.50 9.08 9.44 8.90 9.58 9.01 9.67 9.11 9.64 9.47 9.26 Overall Means 2 None N N-P-K None N N-P-K None N N-P-K None N N-P-K 428 419 442 315 344 323 376 364 359 252 264 299 Overall Means 2 Superior Superior Superior Superior Superior Superior Overall Means 2 Variety Variety None Fumigant Fumigant Vorlex Foliar Fertilizer None Foliar Fertilizer N Foliar Fertilizer N-P-K 1 Foliar N was applied in 5 applications as urea in 5 gallons of water to supply 2 lb N/A in each application. Foliar N-P-K was applied in 5 applications as a 20-20-20 foliar fertilizer in 5 gallons of water to supply 2 lb N, P2O5, and K20/A in each application. 2 Any two treatment means followed by different letters are significantly different (p = .05). 3 Sampled on July 23. empty table cell4,494 a empty table cell7,092 b empty table cell5,862 empty table cell5,724 empty table cell5,810 empty table cell5,725 empty table cell5,844 0.21 0.19 0.18 a 0.22 b 0.20 0.20 0.20 0.69 b 0.47 a 0.61 b 0.55 a 0.59 0.57 0.58 0.85 0.87 0.93 b 0.79 a 0.87 0.85 0.82 376 b 319 a 398 b 297 a 343 345 355 9.24 9.36 9.22 9.38 9.26 9.39 9.26 Overall Means 2 Atlantic Superior 53 54 53 53 52 54 55 33 34 34 33 34 34 34 6 5 5 5 5 5 6 29 23 23 28 26 26 25 Table 9. Elemental composition on potato petioles as affected by variety, soil fumigant and the application of foliar fertilizers. Elemental Content Elemental Content of Potato Petioles 3 Elemental Content of Potato Petioles 3 Elemental Content of Potato Petioles 3 Mn ppm Elemental Content of Potato Petioles 3 Fe ppm Elemental Elemental Content of Potato Petioles 3Cu ppm Elemental Content of Potato Petioles 3Zn ppm Content of Potato Petioles 3B ppm 86 108 88 98 68 65 84 79 90 98 132 155 41 38 40 43 41 39 40 39 44 41 42 39 36 34 28 33 26 25 19 22 20 22 30 37 Overall Means 2 11 13 12 12 10 10 12 9 14 13 18 18 Overall Means 2 Overall Means 2 Overall Means 2 Overall Means 2 Treatments 1 Soil Fumigant None None None Vorlex Vorlex Vorlex None None None Vorlex Vorlex Vorlex Atlantic Superior Treatments 1 Foliar Fertilizer Elemental Content of Potato Petioles 3 P % Ca % Mg % of Potato Petioles 3 K % 7.99 8.06 8.66 9.24 8.58 8.82 8.52 9.48 9.38 9.22 9.84 9.28 1.33 1.31 1.32 1.15 1.17 1.14 1.60 1.50 1.70 1.34 1.38 1.33 None N N-P-K None N N-P-K None N N-P-K None N N-P-K NO3-N Elemental Content of Potato Petioles 3 -ppm— 1,970 2,060 2,317 2,010 2,060 1,777 3,433 5,033 4,400 3,733 3,667 4,600 1.47 1.44 1.44 1.22 0.80 1.34 1.00 0.92 0.93 0.90 0.97 0.89 Overall Means 2Overall Means 2 0.17 0.18 0.18 0.21 0.20 0.20 0.16 0.16 0.17 0.20 0.19 0.17 Overall Means 2Overall Means 2 Overall Means 2 empty table cell 2,032 a empty table cell4,144 b empty table cell3,202 empty table cell2,974 empty table cell2,787 empty table cell3,205 empty table cell3,273 8.56 a 9.29 b 8.68 a 9.16 b 8.74 8.99 9.03 0.19 0.17 0.17 0.19 0.18 0.18 0.18 624 568 638 418 492 527 587 621 535 420 416 478 Overall Means 2 Variety Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Superior Superior Superior Superior Superior Superior Overall Means 2Overall Means 2 Variety Variety Fumigant Fumigant None Vorlex Foliar FertilizerNone N Foliar Fertilizer Foliar FertilizerN-P-K 1.24 a 1.47 b 1.46 b 1.25 a 1.36 1.34 1.37 1.29 b 0.94 a 1.20 b 1.02 a 1.15 b 1.03 a 1.15 b 544 86 510 107 595b 89 458a 103 512 92 97 524 544 100 40 41 40 41 41 40 41 11 14 12 14 12 12 14 30 25 26 29 28 28 27 1 Foliar N was applied in 5 applications as urea in 5 gallons of water to supply 2 lb N/A in each application. Foliar N-P-K was applied in 5 applications as a 20-20-20 foliar fertilizer in 5 gallons of water to supply 2 lb N, P2O5, and K2O/A in each application. 2 Any two treatment means followed by different letters are significantly different (p = .05). 3 Sampled on August 2. Table 10. Nutrient composition of potatoes as affected by fertility treatments. Treatment # July 18 Sampling Dates July 30 August 9 Sampling Dates August 20 Sampling Dates Sampling Dates empty table cell % P 1 2 3 empty table cell 1 2 3 empty table cell 1 2 3 % K % Ca empty table cell % Mg 1 2 3 .113 a 1 .123 b .123 b 8.55 a 8.46 a 8.76 a 2.35 a 2.14 a 2.25 a 1.32 a 1.21 a 1.22 a empty table cell Mn ppm 1 2 3 empty table cell 165 a 157 a 162 a % P % K % Ca % Mg .091 a .091 a .097 a 8.47 a 8.97 a 9.19 a 2.18 a 2.22 a 2.24 a % P % K % P .093 a .106 b .104 b % K 8.12 a 8.27 a 8.64 a % Ca % Ca 2.20 a 2.28 a 2.24 a % Mg % Mg .091 a .095 a .095 a 5.95 a 6.16 a 6.83 a 2.11 a 2.15 a 2.07 a 1.64 a 1.56 a 1.53 a 2.39 a 2.41 a 2.17 b Mn ppm Mn ppm Mn ppm 232 a 240 a 234 a 182 a 179 a 195 a 2.03 a 2.09 b 1.94 a 207 a 205 a 214 a Zn ppm Zn ppm 1 2 3 empty table cell 36.3 a 38.5 a 36.3 a NO3 ppm 33.3 a 37.0 a 36.0 a NO3 ppm Zn ppm 25.8 a 23.3 a 24.8 a NO3 ppm Zn ppm 21.0 a 22.0 a 34.5 a NO3 ppm 1 2 3 27125 a 26375 a 27875 a 24125 a 24375 a 25250 a 20900 a 21450 a 21300 a 13650 a 14925 a 14250 a 1 Column means followed by the same letters are not significantly different as determined by the Least Significant Different Test (.05). Table 11. Influence of Vorlex, foliar nutrient applications and potato varieties on the root-lesion nematode. Pratylenchus Pratylenchus Pratylenchus penetrans Pi/100 cm 3 Soil (5/1/84) penetransPm (8/7/84) penetrans Pm (8/7/84) 100 cm 3 Soil 1.0 g Root Pratylenchus penetransPf Pm (8/7/84) Total (9/20/84) 22 a 41 a 18 a 25 a 32 a 38 a 23 a 29 a 28 a 22 a 36 a 40 a 43 a 47 a 29 a 50 a 42 a 39 a 43 a 38 a 40 a 37 a 50 a 53 a 69 a 48 a 42 a 61 a 87 a 98 a 68 a 79 a 59 a 59 a 69 a 65 a 112 a 95 a 71 a 111 a 129 a 137 a 111 a 117 a 99 a 96 a 96 a 120 a 73 a 52 a 45 a 50 a 68 a 62 a 62 a 53 a 79 a 47 a 61 a 61 a Treatment Superior Vorlex N-P-K Superior Vorlex N Check Superior Vorlex No Vorlex Superior N-P-K Superior No Vorlex N Superior No Vorlex Check Atlantic Vorlex N-P-K Atlantic Vorlex N Check Atlantic Vorlex Atlantic No Vorlex N-P-K Atlantic No Vorlex N Check Atlantic No Vorlex Table 12. Influence of Vorlex, foliar nutrient applications and potato varieties on the root-lesion nematode. Pratylenchus penetrans Pm Pratylenchus penetrans Pratylenchus penetransPm (8/7/84) Pm (8/7/84) (8/7/84) 100 cm 3 Soil 1.0 g Root Pratylenchus penetransPf Total (9/20/84) Pratylenchus penetrans Pi/100 cm 3 Soil (5/1/84) 29 a 30 a 27 a 32 a 23 a 35 a 31 a 42 a 44 a 40 a 46 a 43 a 34 a 40 a 68 a 67 a 61 a 74 a 64 a 71 a 51 a 110 a 107 a 101 a 120 b 107 a 105 a 91 b 58 a 61 a 61 a 58 a 58 a 59 a 62 a Treatment Variety Superior Atlantic Variety Fumigant Vorlex No Vorlex Fumigant Foliar Fertilizer N-P-K Foliar Fertilizer N Check Foliar Fertilizer EFFECT OF HELD PRODUCTION TREATMENTS, PRESTORAGE HANDLING, CHEMICAL AND MECHANICAL TREATMENTS AND STORAGE ENVIRONMENTS OF POTATOES OUT OF EXTENDED STORAGE B.F. Cargill, R.L. Ledebuhr, K.C. Price, T.D. Forbush and H.S. Potter Department of Agricultural Engineering and Botany and Plant Pathology INTRODUCTION The following three reports contain the results of three potato storage pro­ jects that were partially funded by the Michigan Potato Industry Commission. All the potatoes in the projects were evaluated as follows: Weight loss: All bagged samples were weighed at harvest; after two weeks suberization and at market quality evaluation dates. The weight loss during storage is represented by a percent using the following equation: Wi = harvest weight We = evaluation weight The weight loss factor (WLF) is the weight loss percent per day and is found by: This factor is an important "marketing tool" for the grower. The WLF can be used to help the grower determine the economics of when to market potatoes based only on the loss of weight during storage. Other factors such as loss in quality, market price, and storage operation costs influence when to market potatoes. Market quality: Market quality evaluations involved removing the respective bagged samples from storage, examining each individual tuber, and classifying them as follows: A. Marketable B. Non-marketable 1. 0 to 5.0% 2. 5.1% - 10% 3. 10.1% - 25% 4. over 25% dry rot dry rot dry rot dry rot 5. 0-5% 6. 5.1% - 10% 7. 10.1% - 25% 8. over 25% 9. non-storage related problens and soft rot soft rot soft rot soft rot defects (scab, Insects, nemotodes, etc.) After potato classification, the non-marketable potatoes were counted and weighed. Market quality is a percentage of the total sample and is determined by two methods: 1. By number of tubers: Mn = number of marketable potatoes in each sample Tn = total number of potatoes in each sample 2. By weight of tubers: Mw = weight of marketable potatoes in each sample Tw = total weight of each sample Chip color: Potatoes for chip color evaluation were taken at each market quality evaluation period. Potato samples were fried in vegetable oil at 365°F for 105 - 135 seconds. Samples that did not get a 60 or higher on the Agtron index reading were reconditioned by increasing the storage temperature 5°F/week. Chip color evaluations were made weekly during reconditioning until the desired 60 Agtron was reached. Storage temperatures were never elevated above 60°F. EFFECT OF FIELD PRODUCTION TREATMENTS ON THE MARKET QUALITY OF POTATOES OUT OF EXTENDED STORAGE (1983 MSU INTEGRATED PROJECT - STORAGE PHASE) This report contains data on the effects of various field production treat­ ments on the quality of MSU grown Atlantic potatoes out of extended storage. INTRODUCTION PROCEDURE Potato Samples For the storage phase of the 1983 integrated project, Atlantic potatoes were grown under controlled conditions at the Michigan State University Potato Research Farm at Entrican, Michigan. These potatoes were harvested with the one-row MSU research plot harvester on September 27, 1983. Treatments Four field production treatments were used in this phase of the integrated potato project: 1) check, 2) Temik, 3) Temik and Vorlex applied with a broad­ cast spreader and 4) Temik and Vorlex applied per row. Each of the four treatments were planted on both alfalfa and corn crop rotations. Each treat­ ment also received 225 lb/a of nitrogen. See Table 1. Table 1. Field production treatments for the Atlantic potatoes used in the Treatment 1 number storage phase of the 1983 integrated project. Chemical­ treatment 2 Check Temik Temik & Vorlex - broadcast Temik & Vorlex - row Check Temik Temik & Vorlex - broadcast Temik & Vorlex - row Crop rotation Alfalfa Alfalfa Alfalfa Alfalfa Corn Corn Corn Corn 5A 6A 7A 8A 5C 6C 7C 8C 1 For a detailed discussion of the field production treatments used in this study refer to the 1984 MSU Montcalm Potato Research Report 2 All treatments received 225 lbs/a of nitrogen Storage Environment After harvest all potato samples were bagged, tagged and placed into con­ trolled environment cubicles on the MSU campus. The potatoes were suberized at 60°F and 95% r.h. for one week and 55°F and 95% r.h. for a second week. Following suberization the potatoes were dropped in temperature 5°F/wk until the desired storage environments of 40°, 45°, 50°F, and 95% r.h. was reached. RESULTS AND DISCUSSION Weight Loss Tables 2-4 show the weight loss data for the Atlantic potatoes for the storage phase of the 1985 integrated project. A preliminary statistical analysis on the data coeplied in Tables 2-4 indi­ cates that there is no significant differences between the weight losses of various field treatments. However, temperature effects weight loss during the 194 day storage duration. There is a 5.1% weight loss difference between the 40° and 50°F storage temperatures. Reduced respiration of tubers at the lower storage temperature may effect weight loss. Table 2. Weight loss percentage for Atlantic potatoes of the 1983 integrated project stored at 40° and 95% r.h. 15 Days in storage Days in storage Days in storage86 86 Weight loss Weight loss Days in storage 194 Weight loss 1 See table 1 for a detailed description of the field treatments Table 3. Weight loss percentage for Atlantic potatoes of the 1983 integrated project stored at 45°F and 95% r.h. Treatment 1 number Days in storage15 Weight loss Days in storage86 Days in storage 86 Weight loss Days in storage 194 Weight loss Total Ave. 1 See Table 1 for a detailed description of the field treatments Treatment 1 number 5A 5C Avg. 6A 6C Avg. 7A 7C Avg. 8A 8C Avg. Total Ave. 5A 5C Avg. 6A 6C Avg. 7A 7C Avg. 8A 8C Avg. 1.9 1.9 1.9 3.0 2.0 2.5 2.4 2.6 2.5 2.6 2.3 2.5 2.3 1.2 1.7 1.6 2.2 2.1 2.2 1.7 2.0 1.9 1.9 2.2 2.1 1.9 Days in storage 15 WLF .126 4.0 .126 4.9 .126 4.5 5.0 .200 .133 5.1 .167 5.1 .180 6.3 .173 5.3 .167 5.8 5.2 .173 5.0 .153 .167 5.1 .157 5.1 Days in storage15 WLF .080 .113 .107 .147 .140 .147 .113 .133 .127 .127 .147 .140 .127 3.1 3.7 3.4 4.4 4.1 4.3 4.2 4.1 4.2 3.6 4.5 4.1 4.0 WLF .047 .057 .052 .058 .059 .059 .073 .062 .067 .061 .058 .059 .059 WLF .036 .043 .040 .051 .048 .050 .049 .048 .049 .042 .052 .048 .046 7.7 8.1 7.9 9.1 7.8 8.5 9.1 8.8 8.9 8.7 8.1 8.4 8.4 9.9 11.3 10.6 10.6 10.0 10.3 10.6 10.9 10.8 11.0 9.8 10.4 10.5 Days in storage 194WLF .040 .042 .047 .047 .040 .044 .047 .045 .046 .045 .042 .043 .043 Days in storage 194 WLF .051 .058 .055 .055 .052 .053 .055 .056 .056 .057 .050 .054 .054 Table 4. Weight loss percentage for Atlantic potatoes of the 1983 integrated project stored at 50°F and 95% r.h. Treatment 1 number Days in storage 15 Weight loss Days in storage Days in st orage86 86 194 Days in storage Weight loss Weight loss Days in storage 15 WLF 3.9 .127 3.6 .133 3.8 .133 .180 5.3 .167 5.0 5.2 .273 4.7 .100 3.6 .180 .140 4.2 4.9 .160 4.6 .167 4.8 .167 4.5 .153 WLF .045 .042 .044 .062 .058 .061 .055 .042 .049 .057 .053 .056 .052 1.9 2.0 2.0 2.7 2.5 2.6 1.5 2.7 2.1 2.4 2.5 2.5 2.3 12.2 13.1 12.7 14.8 14.3 14.6 13.5 14.4 14.0 14.5 10.7 12.6 13.5 Days in storage 194 WLF .063 .068 .066 .076 .074 .075 .070 .074 .072 .075 .055 .065 .070 5A 5C Avg. 6A 6C Avg. 7A 7C Avg. 8A 8C Avg. Avg. 1 See Table 1 for a detailed description of the field treatments Market Quality The market quality data (% by weight) of the Atlantic potatoes of the 1983 integrated project are shown in Table 5. A preliminary statistical analysis on the market quality data compiled into Table 5 suggests that the different field production treatments used in the 1983 integrated project have no significant affect on market quality of pota­ toes out of extended storage. However, there is a slightly significant difference (5.7%) between the 40°F and 50°F storage temperatures at the 194 day storage duration. Treatment 1 number 5A 5C Avg. 6A 6C Avg. 7A 7C Avg. 8A 8C Avg. Avg. Days in storage 86 40° 98.7 95.8 97.3 96.0 95.5 95.8 94.1 97.4 95.8 94.2 97.8 96.0 96.2 Days in storage 86 45° 97.3 97.6 97.5 96.3 95.1 95.7 96.7 95.7 96.2 96.8 93.3 95.1 96.1 50° 97.8 99.5 98.7 95.3 97.5 96.4 96.3 94.7 95.5 95.1 96.3 95.7 96.6 Days in storage 194 45° 98.2 95.2 95.7 95.0 95.6 95.3 91.7 94.9 93.3 93.8 95.6 94.7 94.8 Days in storage 194 50° 94.9 92.0 93.5 92.4 90.0 91.2 90.7 89.9 90.3 90.7 93.3 92.0 91.8 40° 99.2 97.6 94.8 96.8 99.1 98.0 98.5 98.9 98.7 99.5 97.3 98.4 97.5 Table 5. Market quality (% by weight) of MSU grown Atlantic potatoes stored at 40°, 45°, and 50°F and 95% r.h. for 86 and 194 days. Days in storage 86 Days in storage 194 1 See Table 1 for a detailed description of the field treatments Chip Color Tables 6-7 present the chip color data for the 1983 Atlantic potatoes stored in the MSU cubicles. The 40° and 50°F cubicles had mechanical problems several times during their storage duration and storage temperatures were found to be ±5°F than the desired storage temperature and thus the reconditioning time for these pota­ toes is much greater than those stored at 45°F. Apart from mechanical problems the data in Table 7 shows that the different field treatments had no affect on chip color quality. Table 6. Agtron chip color data for 1983 Atlantic potatoes stored at 40°, 45° and 50°F for 86 days. Original Storage temperature 1 F After 86 days storage 40° 45° 50° 50 60+ 50 Reconditioning Time Reconditioning Time 2 weeks Reconditioning Time 1 week 55-60 50-55 - 55-60 55 - 3 weeks 60+ - 60+ Table 7. Agtron chip color for the eight different field treatments of the 1983 Atlantic potatoes stored at 40°, 45°, and 50°F for 194 days. temp.°F and Original storage treatment 1 number 40°F 1 50 After 194 days storage 45°F 1 50°F 1 40°F 4 40°F 7 45°F 2 45°F 3 45°F 4 45°F 5 45°F 6 45°F 7 45°F 8 4 50°F 7 50°F 60+ 50 45-50 50 60+ 60+ 60+ 60+ 60+ 60+ 60+ 50 50 Reconditioning time Reconditioning time Reconditioning time 50-55 - - - 50-55 1 week 50-55 50 - - - - - 50-55 50-55 2 weeks 55 - - - - 55 55 50-55 - - - - 55 55 3 weeks 2 55-60 55-60 55-60 - - - - - - - - 55-60 55-60 55-60 1 See Table 1 for a detailed description of the field treatments. 2 All potatoes had an agtron chip color rating of 60+ after 4 weeks of reconditioning. CONCLUSIONS 1. Field production treatments of Temik, a broadcast application of Temik and Vorlex, a row application of Temik and Vorlex and alfalfa and corn crop rotations have no significant affect on weight loss of potatoes out of extended storage. However, the weight loss of the potatoes in the 4O°F storage environnent is slightly less (5.1%) than those stored at 50°F for the 194 day storage duration. 2. Field production treatments of Temik, a broadcast application of Temik and Vorlex, and alfalfa and corn crop rotations have no significant affect on the market quality of potatoes out of storage. However, the market quality of the potatoes in the 40°F storage environment have slightly higher market quality (5.7%) than those stored at 50°F for the 194 day storage duration. 3. Field production treatments used in the 1983 integrated project were found to have no significant affect on chip color of potatoes out of extended storage. However, large variations (above ±5°F) in storage temperature were found to greatly influence the chip color reconditioning tine. QUALITY/MARKETABILITY OF POTATOES OUT OF EXTENDED STORAGE DUE TO PRESTORAGE HANDLING, CHEMICAL AND MECHANICAL TREATMENTS AND STORAGE ENVIRONMENTS The following report contains the results of the effect of prestorage mechani­ cal and chemical treatments on potato market quality out of extended storage. INTRODUCTION PROCEDURE Potato Samples The 1983 Atlantic potatoes were harvested from the Integrated plot at Michigan State University's Potato Research Farm at Entrican, Michigan using the one row plot harvester. Equipment The Lockwood bin piler at Sandyland Farms was used for all potato treatments; chemical and mechanical. For chemical treating the Microtec, an application system supplied by Micron, Inc., Houston, Texas, was used. The significant components of this system being a diaphragm pump and a Micromax nozzle. Treatments Four prestorage treatments were used: 1) a check sample collected right off the plot harvester, 2) a second check sample collected after the potatoes had run over the bin piler, 3) chemical treating of the potatoes on the bin piler using .42 oz/ton Mertect 340F, .64 oz/ton chlorine (6% active Ingredient), and 1.94 oz/ton of water for a 3 oz/ton solution rate, and 4) chemical treatment using the same methods and solution in #3 except using 1.94 oz/ton of soybean oil as a carrier instead of water. See Table 1. Table 1. Chemical and mechanical treatments of the Atlantic potatoes for the 1983 storage phase. Treatment 1 2 3 4 Mechanical Plot harvester Plot harvester and bin piler Plot harvester and bin piler Plot harvester and bin piler Chemical Check Check .42 oz/ton Mertec 340F, .64 oz/ton chlorine, 1.94 oz./ton H2O .42 oz/ton Mertect 340F, .64 oz/ton chlorine, 1.94 oz/ton soybean oil Storage Environment Immediately after treatment, bagging, tagging, etc. potato samples from treat­ ments 1 - 4 were placed into cubicles on the MSU campus and samples from treatments 2-4 were placed into bulk storage at Sandyland Farms. The cubicles stored potatoes were suberized for two weeks; one week at 60°F and 95% r.h,. and one week at 55°F and 95% r.h. After suberization the pota­ toes were lowered 5°F/week until the desired storage environments of 45° and 50°F and 95% r.h. were obtained. The potato samples in the bulk storage had 24 hour ventilation and were dropped in temperature approximately 1°F every 2 days until the desired storage temperature of 45°F was reached. Residue Evaluation Ten pounds of randomly selected tubers were removed from each treatment for evaluation of TBZ residue. The potato assay for thiabendazole was performed from opposite quarters of each tuber. This chemical evaluation was performed in the chemical laboratories of Merck and Company, Rahway, New Jersey. RESULTS AND DISCUSSION Weight Loss The weight loss for the 1983 Atlantic potatoes stored at 45° and 50°F at the MSU cubicles and at Sandyland Farms is shown in Table 2. Table 2. Weight loss for the 1983 treated Atlantic potatoes stored at 45° and 50°F and 95% r.h. at the MSU cubicles and Sandyland Farms. Treatment 2 Storage duration 1 and storage temperature83 days Storage duration 1 and storage temperature 45°F 184 days Storage duration 1 and storage temperature184 days 50°F Storage duration 1 and storage temperature 83 days 50°F 4.8 5.6 6.3 5.4 45°F 3.9 5.0 4.9 4.5 Storage duration 1 and storage temperature 125 Storage duration 1 and storage temperature 125 days 50°F - - - - days 45°F — 5.7 5.9 5.7 1 2 3 4 1 Potatoes were stored in the MSU cubicles for the 83 and 184 day storage duration. Potatoes at the 125 day storage duration were stored at Sandyland Farms. 2 See Table 1 for a detailed description of the treatments - 12.7 12.3 11.0 - 9.5 10.6 8.8 A preliminary statistical analysis shows that there is a slightly significant difference (at the 25% level) in weight loss for treatment 4 for the 45°F storage temperature at the 125 and 184 day storage duration. This suggests the possibility that the potatoes treated with the 3 oz/ton solution with soybean oil carrier may have a slightly lower weight loss at longer storage durations. The preliminary statistical analysis also showed a slightly significant dif­ ference (at the 25% level) between treatment 1 and treatments 2 - 4 at the 83 day storage duration. Treatment 1 is a check from the MSU plot harvester and it would be expected to have a slightly lower weight loss than treatments 2-4 which due to more mechanical handling had a lower bruise-free percentage than treatment 1. Market Quality The market quality of the treated 1983 Atlantic potatoes stored at 45° and 50°F at the MSU cubicles and at Sandyland Farms is presented in Table 3 and Figures 1 and 2. Table 3. Market quality (% marketable weight) and deposition for the 1983 treated Atlantic potatoes stored at 45° and 50°F and 95% r.h. at the MSU cubicles and Sandyland Farms. Storage duration 1 83 days 45°F 95.9 92.0 93.7 95.0 Storage Storage duration 1 125 days 45°F Storage duration 1 125 days 50°F Storage - 92.6 91.0 89.2 - - - - duration 1 83 days 50°F 96.7 91.6 92.2 94.7 duration 1 184 days 45°F Storage duration 1 184 days 50°F - 89.6 86.8 94.2 - 94.3 91.9 88.7 Chemical deposition (ppm) - - .42-.45 2.46-2.50 Treatment 1 1 2 3 4 1 Potatoes for the 83 and 184 day storage duration were stored at the MSU cubicles. Potatoes for the 125 day storage duration were stored at Sandyland Farms. 2 See Table 1 for a detailed description of treatments A preliminary statistical analysis on treatment 1 vs. treatment 2 stored at 45° and 50°F for 83 days shows that there is a significant difference (at the 10% and 2.5% level respectively) in market quality between these treatments. Treatment 1 vs. treatment 2 at the 45°F and 154 day storage duration is sig­ nificant to the 5% level. Treatment 1 is a check from the MSU plot harvester and treatment 2 is a check taken after the potatoes had run over the bln piler at Sandyland Farms. Treatment 2 has a lower bruise-free percentage so it is expected that it would have a decrease in market quality due to the increased bruising from mechani­ cal handling. The statistical analysis also showed that there is a significant difference (at the 25% level) between treatment 2 and treatment 4 at the 45° and 50°F temperatures stored for 83 days. For the 45°F temperature storage at the 184 day storage duration there is a significant difference (at the 10% level) between treatment 2 and treatment 4. Since the chemical residue of treatment 4 is 2.46 - 2.5 ppm the data would suggest that a significant increase in market quality may occur when chemical deposition reaches or exceeds 2.46 - 2.5 ppm. Fig. 1. Market Quality vs Chemical (TBZ) Deposition for the 1985 Atlantic Potatoes Stored at 45°F and 95% r.h. for 83 days. Fig. 2. Market Quality vs Chemical (TBZ) Deposition for the 1983 Atlantic Potatoes Stored at 50°F and 95% r.h. for 33 days. Chip Color Table 4 presents the chip color data for the 1983 Atlantic potatoes stored at Sandyland Farms, Howard City, MI for 125 days. This data shows that chemical treatments have no affect on the quality of chip color out of storage. See Table 4. Table 4. Chip color data for potatoes stored at 45°F at Sandyland Farm for 125 days. Treatment 1 125 days storage Reconditioning time 1 week Reconditioning time 2 weeks Reconditioning time 3 weeks 2 3 4 1 See Table 1 for a detailed description of the treatments - - - - - - 60+ 60+ 60+ - - - CONCLUSIONS 1. Reducing bruise levels will reduce weight loss and increase market quality of potatoes out of storage. 2. Prestorage chemical treatments have no significant affect on weight loss or chip color of potatoes out of storage. 3. Low volume prestorage chemical treatments with a deposition of 2.46 - 2.5 or more show a significant increase in market quality over non-treated equivalently handled potatoes. INFLUENCE OF LOW VOLUME PRESTORAGE CHEMICAL TREATMENT ON THE MARKET QUALITY OF COMMERCIALLY PRODUCED POTATOES INTRODUCTION This phase of the storage project reports on the affects of low volume pre­ storage chemical treatments on potatoes at the commercial level. All potato production, harvest, handling and chemical treating was performed at Sackett Ranch, Inc., Stanton, Michigan. PROCEDURE Chemical Treatment Two treatments were used for the commercial treatment phase of the storage project: 1) a check with no chemical applied and 2) a chemical treatment with a 3 oz/ton solution consisting of .42 oz Mertect 340F, .64 oz chlorine and 1.94 oz water. See Table 1. Table 1. Prestorage chemical treatments used on commercially produced and handled potatoes. Treatment Chemical Solution 1 2 Check 3 oz/ton solution consisting of .42 oz Mertect 340F, .64 oz chlorine and 1.94 oz water Storage Immediately after treating, samples from the two treatments were weighed, bagged, tagged and put into the MSU cubicles. The potatoes were suberized for one week at 60°F and 95% r.h. and 95% r.h. and a second week at 55°F and 95% r.h. From there the storage temperature was lowered 5°F/week until the desired storage environment of 45°F and 95% r.h. was reached. RESULTS AND DISCUSSION Table 2 presents the data for the low volume commercial prestorage chemical treatment at Sackett Ranch, Inc., Stanton, Michigan. Table 2. Market quality (% by weight) for non-treated vs low volume prestorage chemi4cally treated potatoes Treatment 1 Market quality (% by weight) Check Treated 81.3 92.7 1 See Table 1 for a detailed description of treatments. A statistical analysis shows that there is a very significant difference, (11.4%), (at the 1% level) between the treated and non-treated potatoes. The market quality percentage of the check samples is influenced less than 2% by bacterial soft rot. Treated samples had no bacterial soft rot. An 11.4% increase could mean a gross savings of approximately $10,260.00 for a 15,000 cwt storage bin (at $6/cwt). CONCLUSIONS 1. The 3 oz/ton solution consisting of .42 oz Mertect 340F, .64 oz chlorine and 1.94 oz of water used in the prestorage treatment of potatoes can significantly increase the market quality of potatoes out of extended storage. CORN HYBRIDS, PLANT POPULATIONS AND IRRIGATION E.C. Rossman and Keith Dysinger Department of Crop and Soil Sciences Performance data for 62 commercial corn hybrids evaluated in 1984 with and without irrigation are presented in Table 1 along with two- and three-year averages for those tested in 1983 and 1982. One inch of water was applied through a sprinkler system on each of 8 dates (July 2, 10, 19, 27, August 8, 17, 25 and September 4) for a total of 8 inches of irrigation. Rainfall was: April = 2.78”, May = 5.14", June = 2.93", July = 3.76", August = 1.97", September = 3.90" and October = 2.88". Irrigated yields averaged 83.7 bushels more than nonirrigated - 152.3 vs. 68.6, an increase of 122%. Hybrids ranged from 114.4 to 186.5 with irrigation and 43.2 to 87.2 without irrigation. Hybrids significantly better than average yield (arranged in order of increasing grain moisture content at harvest) are listed below. Seventeen of the twenty hybrids were in the highest yielding group for both irrigated and nonirrigated plots. Irrigated Not Irrigated Pioneer 3901 Funk G-4256 Super Crost 2288 Stauffer Seeds S4402 Pioneer 3744 Super Croat 1940 Great Lakes GL-466 Pioneer 3737 Jacques 5400 Funk 3012X P-A-G SX193 P-A-G SX195 Funk G-4342 Andersons PSX-100 Golden Harvest H-2448 DeKalb-Pfizer T1000 Payco 872 MFI 1812 MFI 1776 Golden Harvest H-2480 Pioneer 3901 Funk G-4256 Super Crost 2288 Stauffer Seeds S4402 Pioneer 3744 Great Lakes GL-466 Pioneer 3737 Jacques 5400 Funk 3012X P-A-G SX193 P-A-G SX195 DeKalb-Pfizer DK484 Funk G-4342 Golden Harvest H-2448 DeKalb-Pfizer T1000 MFI 1812 Great Lakes GL-516 MFI 1776 Golden Harvest H-2480 The correlation of irrigated with nonirrigated yields was highly significant, .773, Indicating that hybrids tended to respond alike in both situations. During the 17-year period, 1968-1984, the correlations have ranged between .7 and .9 except for 1976 when it was .490. All correlations have been highly significant. Average, highest and lowest yields for corn hybrids irrigated and not irrigated for the 17-year, 1968-1984, are given in Table 2. The average yielding hybrids have yielded 49 more bushels when irrigated. The highest yielding hybrids have responded with 63 bushels added yield while the lowest yielding hybrids have given only 33 bushels added yield when irrigated. These results demonstrate the importance of choosing high yielding hybrids to maximize returns from irrigation with little, if any, additional cost. There was twice as much stalk lodging (2.7 vs. 5.3%) on nonirrigated plots. This agrees with most (but not all) of the previous years when there has been less lodging on the irrigated plots. Generally, stressed weaker plants on nonirrigated plots have been more susceptible to lodging. Plant Population x Hybrids Five adapted hybrids at four plant populations irrigated and not irrigated have been grown in each of 17 years, 1968-1984, Table 3. Over the 17-year period, a harvest plant population of 23,300 has given the highest average yield (167 bushels per acre) when irrigated while 19,290 has given the highest yield (106 bushels) without irrigation. The 23,300 population has given the highest yield in 14 out of 17 years (1973, 1979 and 1981 being the exceptions). The irrigated yields in 1984 were 160, 168, 179 and 176 for harvest populations of 15,300, 19,290, 23,300 and 27,460, respectively. The 17-year average increase due to irrigation is 69 bushels per acre at the 23,300 population. Nonirrigated yields were 76, 78, 71 and 63 for the same four populations in 1984. Stalk lodging has increased with increasing plant population. In 1984, there was 2-5 times more lodging at 27,460 than there was at 15,300. Moisture content of grain at harvest has averaged 1-2% higher for the two higher populations. TABLE 1 NORTH CENTRAL MICHIGAN MONTCALM COUNTY TRIAL-IRRIGATED VS NOT IRRIGATED ONE, TWO, THREE YEAR AVERAGES - 1984, 1983, 1982 ZONE 3 HYBRID (BRAND-VARIETY) % MOISTURE % Moisture 2 YR 1984 % BUSHELS PER ACRE 1984 BUSHELS PER ACRE BUSHELS PER ACRE 2 YR IRR BUSHELS PER ACRE 2 YR NON IRR -- Moisture 3 YR PRO-SEED HYLAND HL-2414 FUNK 2011X KING K2203 KING K2204 PRO-SEED HYLAND LG18 STAUFFER SEEDS S2202 STANTON SX90 SUPER CROST 1621 PRO-SEED HYLAND HL-2444 FUNK 1011X JACQUES EXP. 3091 *+PIONEER 3901 GREAT LAKES GL-422 ANDERSON PSX93 GREAT LAKES GL-487 *+FUNK G-4256 LAND O"LAKES LOL-1096 DAIRYLAND DX1097 PAYCO SX620 *+SUPER CROST 2288 P-A-G SX180 *+STAUFFER SEEDS S44O2 STANTON SX95 *+PIONEER 3744 DAIRYLAND DX1003 DEKALB-PFIZER DK447 STAUFFER SEEDS S3306 PRO-SEED HYLAND HL-2454 *SUPER CROST 1940 PRIDE 4422 *+GREAT LAKES GL-466 KING K4422 *+PIONEER 3737 *+JACQUES 5400 NORTHRUP KING PX9902 P-A-G SX175 PIONEER 3747 DEKALB-PFIZER DK505 GARNO S-92X *+FUNK 3012X -- -- -- -- -- 23 -- -- -- 24 24 -- -- -- 23.3 23.7 -- -- 23.9 -- 23.9 -- 24. 1 -- 24.3 24 24.4 24.7 -- -- 24.7 -- 24.8 24.8 -- 24.9 25 25.2 25 25.2 25 -- 25.3 -- -- -- -- 25.4 -- -- 25.4 -- 25.5 -- 25.5 26 -- 25.8 -- -- -- -- 25.8 -- -- 26.0 26.0 26 26. 1 27 27 26. 1 -- 26.2 -- 26.3 -- 26.4 26.5 27 -- 26.5 26.6 28 26.6 27 -- 26.7 -- 26.8 -- 26.8 -- 26.8 26.8 27 -- 26.9 26.9 -- 27.0 -- 25 25 25 -- -- -- -- -- 26 -- -- -- -- -- -- -- -- -- % Stalk Lodging % Stalk Lodging 2 YR IRR 3 BUSHELS PER ACRE YR 1984 % Stalk Lodging IRR 2.6 0.8 1.4 2.1 3.4 BUSHELS PER ACRE 3 YR NON IRR -- -- -- -- -- -- -- -- -- -- 5.3 5.6 2.2 2.5 1.4 74 IRR -- -- -- -- -- -- -- -- -- -- 135 135 56 1984 NON IRR 43.2 -- 71.4 -- 63. 1 -- 57.5 -- 69.8 -- 50.2 -- 58.1 61.7 -- 49.8 -- 52.3 -- 51.7 -- 79.2 67.4 53.3 64.2 -- 78.3 -- 60.2 -- 56.4 -- 58.0 81.6 -- 67.8 -- 80.0 -- 60.8 80.0 69.4 64.7 -- 74.3 -- 67.0 -- 73.0 66.2 -- 79.4 60. 1 87.2 -- 77.6 -- 49.0 -- 75.3 -- 61.1 66.9 -- 66.1 -- 84.0 -- 173 152 135 145 141 176 173 170 166 167 148 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- IRR 115.0 156.5 146.3 146.7 152. 1 114.4 139.7 153.4 118. 1 139.5 135.9 174.7 158.0 128.8 157.4 172.2 123.3 131.7 138.9 171.2 152.2 175.2 124.2 168.0 161.7 142.0 156.4 139.3 173.0 151.6 178.0 151.4 186.3 170.6 127.9 165.2 138.4 147.7 147.8 186.5 -- 77 67 50 -- 62 85 75 169 155 -- -- -- -- -- 59 -- -- -- -- 150 171 167 -- -- -- -- -- 164 -- -- -- -- -- -- 69 -- -- -- -- -- 76 71 72 93 86 -- 83 99 88 -- 90 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 7.4 0.7 0.9 0.8 2.2 1.5 1.5 5. 1 1.7 5.0 1984 NON IRR 9.2 -- 3.6 -- 3.7 -- 4.2 -- 8.5 -- 11.5 -- 3.9 2.5 -- 5.7 -- 8.4 -- 12.5 -- 4.3 1.6 4.6 6.1 -- 4.1 -- 0.0 -- 4.6 -- 7.0 7.5 -- 8.5 -- 10.9 -- 4.5 4.8 4.5 6.3 -- 1.5 -- 2.2 -- 9.8 6.7 -- 8.1 5.4 7.0 -- 4.4 -- 4.8 -- 6.2 -- 3. 1 3.5 3.0 2.6 -- 3.0 3.0 12.1 -- 4. 1 -- 2.9 4.3 5.3 0.9 2.2 3.6 4.3 1.4 2.9 2.8 3.0 4.8 0.8 1.6 2.1 1.6 4 4 3 3 6 3 4 7 5 9 4 6 % Stalk Lodging 3 YR NON IRR -- -- -- -- -- -- -- -- -- -- 5 % Stalk Lodging 2 YR NON IRR -- -- -- -- -- -- -- -- -- -- 4 9 5 5 10 -- 7 3 6 -- 8 9 5 4 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- % Stalk Lodging 3 YR IRR -- -- -- -- -- -- -- -- -- -- 3 4 4 -- -- 3 3 5 -- 7 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 8 7 -- -- 10 5 7 -- 8 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- TABLE 1 (CONTINUED) NORTH CENTRAL MICHIGAN MONTCALM COUNTY TRIAL-IRRIGATED VS NOT IRRIGATED ONE, TWO, THREE YEAR AVERAGES - 1984, 1983, 1982 ZONE 3 BUSHELS PER ACRE BUSHELS PER ACRE BUSHELS PER ACRE 1984 BUSHELS PER ACRE 1984 NON IRR 2 YR IRR 2 YR NON IRR BUSHELS PER ACRE 3 YR 1984 % Stalk Lodging 3 BUSHELS PER ACRE YR NON IRR 1984 NON IRR IRR IRR % Stalk Lodging % Stalk Lodging 2 YR % Stalk Lodging 3 YR NON IRR IRR 0.0 2.92 IRR 47 HYBRID (BRAND-VARIETY) % MOISTURE % MOISTURE 2 YR 1984 3 % MOISTURE YR DAIRYLAND DX1096 GREAT LAKES GL-522 *+P-A-G SX193 DAIRYLAND DX1001 DEKALB-PFIZER EXP348 *+P-A-G SX195 STANTON SX100 PRO-SEED HYLAND LG22 DEKALB-PFIZER T950 +DEKALB-PFIZER DK484 *+FUNK G-4342 *ANDERSONS PSX-100 *+GOLDEN HARVEST H-2448 *+DEKALB-PFIZER T1000 GOLDEN HARVEST EX638 FUNK 3026X GREAT LAKES GL-51O * PAYCO SX872 *+MFI 1812 +GREAT LAKES GL-516 *+MFI 1776 *+GOLDEN HARVEST H-2480 27.0 26 27.2 28 27.2 28 -- 27.2 27.4 -- 27.4 -- 27.5 27 27.6 -- 27.7 28 27.8 28 -- 27.9 -- 28.3 -- 28.4 28.6 29 -- 28.6 -- 29. 1 -- 29. 1 29,4 30 29.5 31 -- 29.6 30.3 29 31.6 30 25 27 -- -- -- -- 27 -- 27 -- -- -- -- 28 -- -- -- -- -- -- -- -- IRR 132.6 165.7 169.0 131.9 164.6 173.7 120.4 134.9 155.8 165.4 176.5 167.8 171.5 177.9 159.2 155.4 156.3 169. 1 174.0 160.0 178.3 176.5 51.8 74.7 77.0 62.3 -- 75.5 -- 79.2 -- 54.3 66.7 -- 63.4 77.5 80.2 -- 73.4 -- 80.6 -- 79.4 74.0 -- 68.2 -- 73.9 -- 74.7 80.6 79.4 -- 76.7 77.8 138 171 149 136 160 180 173 160 173 168 170 -- -- -- -- -- -- -- -- -- -- -- 60 58 79 70 144 173 -- -- -- -- 139 -- 65 150 80 -- -- -- -- 171 -- -- -- -- -- -- 74 -- 76 -- 70 78 74 80 77 77 97 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 91 0.8 2.8 3.7 2.9 3.4 4.0 1.7 2.9 3.0 3.6 2.8 2.4 3.6 5.2 2.8 2.9 2.2 3.1 1.4 2.8 1.4 5 7 5 2.2 2.8 11 5.7 -- 5.0 -- 5.1 -- 11 3.6 3.9 -- 8.9 5.8 12.6 -- 5.8 -- 2.4 -- 8.1 4.2 -- 0.7 -- 8.6 -- 3.4 5.9 3.6 -- 3.8 2.2 6 5 7 6 7 -- -- -- -- -- -- -- -- -- -- 6 9 7 -- 6 6 9 6 8 % Stalk Lodging 2 YR NON IRR 6 3 7 [% Stalk Lodging 3 YR 3 -- 10 5 -- 6 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 5 -- 8 10 7 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- TABLE 1 (CONTINUED) NORTH CENTRAL MICHIGAN MONTCALM COUNTY TRIAL-IRRIGATED VS NOT IRRIGATED ONE, TWO, THREE YEAR AVERAGES - 1984, 1983, 1982 ZONE 3 HYBRID (BRAND-VARIETY) % MOISTURE % MOISTURE 2 YR 1984 % MOISTURE 3 YR BUSHELS PER ACRE 1984 BUSHELS PER ACRE BUSHELS PER ACRE 1984 NON IRR 2 YR IRR IRR % STALK LODGING % STALK LODGING % STALK LODGING 3 BUSHELS PER ACRE 2 YR % STALK LODGING YR 1984 3 BUSHELS PER ACRE YR NON IRR 1984 NON IRR IRR BUSHELS PER ACRE 2 YR NON IRR 69 50 TO 85 IRR 157 135 TO 173 % STALK LODGING 2 YR NON IRR 6 3 TO 10 3 YR IRR 5 3 TO 10 % STALK LODGING 3 YR NON IRR 7 5 TO 10 2.7 0.0 TO 7.4 5.3 0.0 TO 12.6 IRR 6 2 TO 11 86 74 TO 99 5 -- -- -- -- -- -- AVERAGE RANGE LEAST SIGNIFICANT DIFFERENCE 26.7 23.3 TO 31.6 27 24 TO 30 25 23 TO 28 152.3 68.6 158 114.4 TO 186.5 43.2 TO 87.2 135 TO 180 1.8 1.2 0.8 14.8 7.7 10 6 8 *SIGNIFICANTLY BETTER THAN AVERAGE YIELD, IRRIGATED, IN 1984 +SIGNIFICANTLY BETTER THAN AVERAGE YIELD, NOT IRRIGATED, IN 1984 empty table cell 1984 1983 1982 PLANTED HARVESTED Soil Type May 2 October 27 Montcalm-McBride sandy loam PREVIOUS CROP POPULATION ROWS FERTILIZER IRRIGATION SOIL TEST: ph Potatoes 21,000 30" 340-125-125 8 inches 6.6 555(very high) SOIL TEST: P 240(high) k SOIL TEST: May 6 October 24 Montcalm-McBride sandy loam May 6 November 3 Montcalm-McBride sandy loam Potatoes 21,400 30" 330-125-125 7 inches 5.8 417(very high) 202(mediurn) Alfalfa 21,000 30" 342-139-139 4 Inches 5.6 562(very high) 251(high) FARM COOPERATOR: Theron Comden, Montcalm Research Farm, Lakeview COUNTY EXTENSION DIRECTOR: William Carpenter, Stanton (1984,1983) James Crosby, Stanton (1982) Table 2. Average, highest and lowest yields for corn hybrids irrigated and not irrigated for 17 years, 1968-1984. AVERAGE AVERAGE Not Irrigated Year 1984 1983 1982 1981 1980 1979 1978 1977 1976 1975 1974 1973 1972 1971 1970 1969 1968 No. of Hybrids Tested 62 59 82 90 71 83 73 74 80 75 76 72 72 56 64 63 56 empty table cell AVERAGE Irrigated 152 151 146 115 126 109 144 125 156 154 112 114 157 163 144 146 136 139 HIGHEST Irrigated 187 195 183 141 167 142 186 158 183 207 134 138 206 211 194 185 182 177 HIGHEST Not Irrigated 87 91 139 111 156 92 112 88 93 157 122 120 179 42 128 109 123 114 LOWEST LOWEST Irrigated Not Irrigated 114 96 109 85 74 67 92 89 120 106 65 78 99 91 95 97 92 92 43 37 83 62 65 42 61 56 49 80 58 73 91 11 70 56 65 59 69 66 113 87 114 67 88 73 72 125 103 101 137 28 103 86 96 90 Table 3. Average yield at four plant populations irrigated and not irrigated for 17 years, 1968-1984. 15,300 15,300 19,290 19,290 23,300 23,300 27,460 27,460 Irrigated Not Irrigated Irrigated Not Irrigated Irrigated Not Irrigated Irrigated Not Irrigated 160 154 150 122 133 123 146 141 153 158 118 108 152 173 122 126 144 141 76 69 120 93 123 77 92 74 72 136 100 97 132 37 91 91 114 95 168 170 168 132 146 140 164 152 174 183 130 134 187 189 144 158 169 160 78 74 131 102 135 87 110 81 84 164 111 116 159 35 112 109 130 106 179 179 177 130 150 138 175 160 181 196 135 128 191 191 158 173 193 167 71 66 124 94 131 83 100 70 81 151 98 106 149 20 93 96 107 98 176 182 176 119 141 131 165 150 161 172 120 108 161 181 151 148 178 153 63 52 117 86 124 78 94 69 68 146 94 102 144 11 85 86 89 92 Year 1984 1983 1982 1981 1980 1979 1978 1977 1976 1975 1974 1973 1972 1971 1970 1969 1968 AVERAGE MONTCALM FARM, 1984 COLORED BEAN BREEDING AND TESTING M.W. Adams, J.D. Kelly, and J. Taylor The materials evaluated consisted primarily of kidney beans, both dark and light red, and of cranberry beans (Table 1). In the case of cranberry beans, we are particularly interested in early-maturing bush beans with larger seed than is normal for standard varieties. In the series of lines numbered 422, 423, 424, and 425, we have bush plant type, early maturity (86 days average as compared to 82 for Taylor Cran and 95 for Cran 028), yield equivalent or better than the latter varieties, and seed sizes of 47 to 50 gms/100 seeds as compared to Taylor Cran with 43 and Cran 028 with 38 gms/100 seeds. In addition, these lines carry the I-gene for resistance to common bean mosaic, the same as Cran 028. Yields were not outstanding in the nursery this year because of the prolonged period without meaningful rainfall. With an LSD of 5.0 cwt, only the bottom 5 entries, all kidney beans, were significantly lower yielding than the top ranking cranberry entries. By and large, the cranberry beans as a group outyielded the kidneys as a group, with a couple of exceptions. The earlier-maturing entries had a slight yield advantage over the later-maturing entries. In Table 2 are presented yield and other data for a group of dark red kidney selections. Most of the 30 entries derived from a cross of Charlevoix by Montcalm, made to recombine halo blight resistance of Montcalm with the test weight of Charlevoix. Seed density scores (lbs/bu) for this group of entries show a range of values between the 56.2 lbs .for Montcalm to the 59.3 lbs for Charlevoix, but unfortunately, the halo blight resistance of Montcalm seems to be genetically linked to the smaller seed size, at least to some degree, and we have not recovered high test weight lines with the halo blight resistance. Again, average yields are low because of the dry weather. Interestingly, the top line, K83222, and the four lowest yielding lines, K83214, K83212, K83210, and K83223, all derive from the same cross, C49242 x Montcalm, backcrossed to Montcalm, which was made to incorporate the ARE-gene for anthracnose resistance into the dark red class. With an LSD of 2.4 cwt, the top and bottom-ranked lines are significantly different in yield. They also differ significantly in seed size. Segregating Populations We had several thousand plants in F2 generations of crosses involving kidney and cranberry seed types, crosses made to broaden the germplasm base in these seed classes. A large number of attractive single plant selections were obtained from these populations and they will be advanced to F3 rows in 1985. EXPERIMENT 4215 MONTCALM STANDARD LARGE SEEDED YIELD TRIAL PLANTING DATE 5/31/84 TABLE OFF UNADJUSTED MEANS TABLE 1. ACCESSION PEDIGREE NO. C66001 MICRAN C81001 CRAN422 C81003 CRAN424 I84015 RKLD/CHARLOTOWN, 4109 C81004 CRAN425 C81009 MVR CRAN C70001 CRAN028 C81002 CRAN423 C81008 T HORT K77002 RKLD/MEC, ISABELLA I81061 SEL-CLRK, SACRAMENTO I81058 REDKLOUD K66001 MANITOU K74002 MDRK/CN (3)- HBR(NEB#1), MONTCALM I82038 8920 (CRAN) K07009 (CRAN) I84016 78734 (Wk) I82037 K60001 DRK/BRAZ.RK,CHARLEVOIX I82028 182027 2602, CHICO 2204, LINDEN I82033 GO1562/RKLD, RUDDY I81103 LRK 9482 AVERAGE OF PRECEDING 22 MEANS LSD (P=.05) (P=.01) LSD COEFFICIENT OF VARIATION ENTRY NO Variable CWT/A Variable PCT SITE MEAN 100 SEED wt. DAYS TO FLOWER HEIGHT LODGING SCORE Variable Variable 1 3 5 13 6 8 2 4 7 15 17 16 22 14 10 21 9 11 12 20 18 19 20.5 20.2 19.2 19.0 18.8 18.8 17.8 17.6 17.3 17.0 16.8 16.2 16. 1 15.9 15.9 15.7 15.4 15.0 13.5 13.5 13. 1 12.3 123.3 121.5 115.4 114.1 113.3 112.9 107.4 106. 1 103.8 102.0 101.3 97.6 97.1 95.6 95.5 94.3 92.7 90.3 81.4 81.4 78.8 74.0 empty table cell empty table cell empty table cell empty table cell 16.6 5.0 6.5 100.0 30.0 39. 1 21.2 21.2 49.9 49.4 47.5 50.4 52.6 42.9 38.0 49.4 43.2 49. 1 51.6 49.7 47.8 50.7 45.9 50.7 45.6 49. 1 45.4 46.5 43.3 43.4 47.4 3.6 4.7 5.4 38.5 38.5 39.0 37.0 37.5 45.0 41.0 39.0 40.0 35.5 35.5 36.0 43.5 41.0 38.5 39.0 2.3 1.8 39.8 2.3 39.0 40.3 1.3 38.3 2.0 33.0 43.5 38.8 38.8 2.0 43.5 4.5 2.3 2.3 1.0 38.8 1.0 41.3 44.8 42.5 37.3 1.8 1.3 1.5 1.8 39.5 41.5 2.5 1.5 1.5 1.5 1.0 46.5 41.3 44.5 41.0 42.0 44.0 43.8 45.8 36.5 43.5 39.8 0.4 0.5 0.7 41.8 41.3 40.9 2.6 3.4 4.5 1.5 1.0 1.8 0.7 0.9 28.2 Experiment 4215 Montcalm Standard Large Seeded Yield Trial PLANTING DATE 5/31/84 EXPERIMENT 4215 MONTCALM STANDARD LARGE SEEDED YIELD TRIAL PLANTING DATE 5/31/84 TABLE OF UNADJUSTED MEANS TABLE 1. (cont.) ENTRY NO. VARIABLE CWT/A DAYS VARIABLE TO MATURITY DES. SCORE VARIABLE 1 3 5 13 6 8 2 4 7 15 17 16 22 14 10 21 9 11 20 12 20.5 20.2 19.2 19.0 18.8 18.8 17.8 17.6 17.3 17.0 16.8 16.2 16. 1 15.9 15.9 15.7 15.4 15.0 13.5 13.5 13.1 12.3 16.6 5.0 6.5 21.2 84.3 86.5 86.5 88.3 85.8 3.3 3.3 3.3 2.8 3.3 96.3 1.8 95.3 86.0 83.0 2.8 87.3 2.5 3.5 2.8 83.0 3.3 89.0 98.3 93.5 82.8 2.8 2.5 2.3 2.8 87.3 97.0 92.0 98.5 97.0 89.0 98.8 2.8 2.8 2.0 2.0 2.3 2.5 2.8 90.2 2.7 3.2 4.1 2.5 0.8 1. 1 21.4 ACCESSION PEDIGREE NO. C6001 MICRAN C81001 CRAN422 C81003 CRAN424 i84015 RKLD/CHARLOTOWN,4109 C81004 CRAN425 C81009 MVR CRAN C70001 CRAN028 C81002 CRAN423 C81008 T HORT K77002 RKLD/MEC, ISABELLA SEL-CLRK, SACRAMENTO I81061 I81058 REDKLOUD K66001 MANITOU K74002 I82038 MDRK/CN( 3 )-HBR(NEB #1), MONTCALM 8920 (CRAN) 78734 (wk) I84016 I82037 K07009 (CRAN) K60001 DRK/BRAZ.RK.CHARLEVOIX I82028 I82027 2602, CHICO 2204, LINDEN I82033 GO1562/RKLD, RUDDY I81103 LRK 9482 AVERAGE OF PRECEDING 22 MEANS LSD (P=.05) (P=.01) LSD COEFFICIENT OF VARIATION 18 19 empty table cell empty table cell empty table cell empty table cell experiment 4215 Montcalm standard large seeded yield trial planting date 5/31/84 EXPERIMENT 4216 MONTCALM PRELIM DARK RED KIDNEY YIELD TRIAL planting date 5/31/84 TABLE 2. TABLE OF UNADJUSTED MEANS ACCESSION PEDIGREE NO. MDRK/CN(3)-HBR(NEB#1), MONTCALM K83222 C49242/3 *MONT K74002 K84009 MONT / CHAR K84003 MONT / CHAR K83215 C49242/4 * MONT K84004 MONT / CHAR K60001 DRK/BRAZ.RK.CHARLEVOIX K83201 K84005 MONT / CHAR K84018 MONT / CHAR *MONT C49242/3 *MONT K84006 MONT / CHAR K83243 C49242/2 K84011 MONT / CHAR K84001 MONT / CHAR K84002 MONT / CHAR K84008 MONT / CHAR K84015 MONT / CHAR K84016 MONT / CHAR K84010 MONT / CHAR K84012 MONT / CHAR ENTRY NO. VARIABLE CWT/A VARIABLE PCT. SITE MEAN 100 SEED WT DAYS TO FLOWER DES. VARIABLE SCORE density VARIABLE LBS/BU. VARIABLE VARIABLE 9 1 20 14 8 15. 2 3 16 29 17 11 22 12 13 18.1 17.9 17.9 17.3 17.1 17.0 16.9 16.8 16.7 16.3 15.9 15.8 15.7 15.4 15.3 19 15.2 15. 1 26 27 15.0 21 14.9 14.9 23 118.5 117.6 3.0 117.4 2.0 113.7 52.241.0 3.0 112.2 2.0 52.3 41.5 3.0 57.5 51.0 56.2 49.3 59.6 56.5 59.1 42.0 41.5 43.5 49.5 111.3 110.6 110.0 109.6 106.7 104.5 103.4 102.9 101.1 100.3 99.8 98.9 98.6 97.8 97.8 49.9 49.0 52.7 49.2 41.0 51.5 41.5 41.5 42.5 41.5 48.5 49.0 47.3 49.5 49. 1 49.4 51.2 49.2 46.4 45.3 42.0 41.0 42.0 40.5 40.0 42.5 41.5 41.5 42.5 42.5 4.0 3.0 3.0 2.0 3.0 3.0 2.0 2.0 3.0 3.0 3.0 2.0 2.0 3.0 57.4 59.3 58.2 57.4 56.6 56.6 56.7 59.2 56.7 56.6 3.0 56.4 58.3 57.8 59.3 58.9 K84007 MONT / CHAR 42.5 K83207 C49242/4*MONT 43.5 K84019 MONT / CHAR 41.5 K84014 MONT/CHAR 41.5 K84017 MONT/CHAR 42.0 K84013 MONT/CHAR 24 13.2 86.446.6 41.0 K83214 C49242/4*MONT 57.4 42.5 K83212 C49242/4*MONT 42.0 57.1 42.5 3.056.6 K83210 C49242/4 *MONT K83223 C49242/3 * MONT 44.0 59. 1 3.0 2.0 3.0 2.0 3.0 2.0 59.2 3.0 3.0 85.6 48.0 80.5 42.0 73.0 45.1 72. 1 44.8 97.2 95.0 92.9 92.7 92.0 56.0 57.6 56.9 59.4 56.6 46.4 47.6 48.0 45.4 47. 1 14.8 14.5 14.2 14.1 14.0 18 4 30 25 28 7 6 5 10 13.0 12.3 11.1 11.0 3.0 AVERAGE OF PRECEDING 30 MEANS LSD (P=.05) LSD (P=.01) COEFFICIENT OF VARIATION empty table cell 15.2 empty table cell 2.4 empty table cell 3. 1 empty table cell 9.6 100.0 15.7 20.4 9.6 48.4 2.7 --- 3.5 4.5 0.9 --- --- 4.4 41.9 0.7 1.0 57.7 1.4 1.9 1.4 EXPERIMENT 4216 MONTCALM PERLIM DARK RED KIDNEY YIELD TRIAL PLANTING DATE 5/31/84 MICHIGAN POTATO INDUSTRY COMMISSION 241 East Saginaw, Suite 403 East Lansing, Michigan 48823 Bulk Rate U.S. Postage PAID Permit No. 979 Lansing, Mich.