1983 MONTCALM FARM RESEARCH REPORT MICHIGAN STATE UNIVERSITY AGRICULTURAL EXPERIMENT STATION IN COOPERATION WITHTHE MICHIGAN POTATO INDUSTRY COMMISSION THE MICHIGAN POTATO INDUSTRY COMMISSION To 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 1983. 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:kk THE MICHIGAN POTATO INDUSTRY COMMISSION • 500 N. HOMER STREET • LANSING, MICHIGAN 48912 • (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. Special acknowledgement is also given to Advanced Drainage Systems (ADS) for their donation of perforated plastic tubing which was used in the installation of a drainage system. Special acknowledgement is also given to the Potato Division of MACMA and Ore-Ida Foods, Inc. for their significant financial support for the purchase and installation of a CR21 Micrologger weather monitoring station. This installation will provide substantially more weather data such as two soil temperatures, air temperature, relative humidity, wind speed, solar radiation, and rainfall. TABLE OF CONTENTS Page. INTRODUCTION, WEATHER, AND GENERAL MANAGEMENT ...................................................................... 1 1983-MICHIGAN POTATO VARIETY EVALUATIONS R.W. Chase, R.B. Kitchen, R. Vander Zaag, R. Leep, and R. Hammerschmidt.......................................... .... 4 EVALUATIONS OF CULTIVARS FOR FROZEN PROCESSING R.W. Chase, R.B. Kitchen, and R Vander Zaag, MSU J. Fuller and R. Smithc, Ore-Ida Foods, Inc...............................................................................17 THE EFFECT OF CHLORINE WASH SOLUTIONS ON CUT SEED POTATOES R. Vander Zaag, R.W. Chase, R. Hammerschmidt, and R. Kitchen...................................... 21 BIOLOGY AND CONTROL OF RHIZOCTONIA AND SCAB DISEASES OF POTATO R. Hammerschmidt........................................................................................... 31 WEED CONTROL IN POTATOES (RESEARCH REPORT) W. Meggitt, R. Leep, R. Chase, G. Powell, and R. Kitchen............................................... 37 BIOLOGY & CONTROL STRATEGIES FOR INSECT PESTS OF POTATOES E.J. Grafius, H.T. Bell, and M.E. Otto ...................................................................................... 41 1983 MICHIGAN POTATO NEMATOLOGY RESEARCH REPORT G.W. Bird........................................................................................................................................................49 FUNGICIDE EVALUATIONS ON POTATOES M.L. Lacy........................................................................................................................................................57 THE INFLUENCE OF SELECTED PRODUCTION MANAGEMENT PRACTICES ON POTATO YIELD, QUALITY, AND NUTRITION M.L. Vitosh, G.W. Bird, R. Hammerschmidt, R.W. Chase, and E. Grafius.....................59 INFLUENCE OF FIELD PRODUCTION TREATMENTS ON THE QUALITY OF POTATOES OUT OF EXTENDED STORAGE (MSU 1982 INTEGRATED PROJECT - STORAGE PHASE) B.F. Cargill, R.L. Ledebhr, K.C. Price, H.S. Potter, R.W. Chase, and M.L. Vitosh.................................................................................................................................. 69 QUALITY OF STORED POTATOES DUE TO PRESTORAGE HANDLING, CHEMICAL AND MECHANICAL TREATMENTS, AND STORAGE ENVIRONMENTS (1982 INTEGRATED PROJECT) B.F. Cargill, R.L. Ledeburh, K.C. Price, H.S. Potter, R.W. Chase, M.L. Vitosh, and J. Cash.................................................................................................................73 QUALITY OF STORED POTATOES DUE TO PRESTORAGE HANDLING, CHEMICAL AND MECHANICAL TREATMENTS, AND STORAGE ENVIRONMENTS (1982 MSU MONONA POTATO PHASE) ........................................................................................................................................ 79 CONTROLLED DROPLET APPLICATION OF MERTECT 340F IN A COMMERCIAL POTATO STORAGE (Lennard & Sons, Samaria, MI) .....................................................................85 CORN HYBRIDS, PLANT POPULATIONS, AND IRRIGATION E.C. Rossman and Keith Dysinger........................................................................................................88 1983 DRY BEAN VARIETY AND STRAIN EVALUATION TRIALS J. Taylor, J. Kelly, A.. Ghaderi, and M.W. Adams.....................................................................94 1983 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 17 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 1983 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 fifteen year temperature and rainfall data recorded at the Research Farm. Maximum temperatures during April and May were 7 degrees cooler than the 15 year average and minimum temperatures were 5 degrees cooler which resulted in very slow emergence. Temperatures changed dramatically in June, July, and August with the average maximum higher than the 15 year average. In June there were 10 days above 81 F and 2 days over 90 F. In July there were 19 days over 81 F and 6 days that it exceeded 90 F and in August there were 17 days and 2 days, respectively. The unseasonably warm growing season, and particularly the warm nights, resulted in reduced yields and specific gravity. Although rainfall from April through September was nearly that of the 15 year average during the months of June, July, and August it was approximately one half of the normal. The high air temperatures and reduced rainfall placed additional stress on the crop. As a consequence, it was necessary to irrigate 17 times throughout the summer. SOIL TESTS Soil test results for the general plot area were: pH 6.2 P 573 K 232 Ca 853 Mg 160 Table 1. The 15 year summary of average maximum and minimum temperatures during the growing season at the Montcalm Research Farm. April Max April Min May Max May Min June Max June Min July Max July Min August Max August Min September Max 56 54 53 47 54 57 48 58 62 50 50 49 56 53 47 54 35 35 31 30 36 36 28 35 37 31 33 31 35 28 28 33 67 65 65 70 63 62 73 63 80 67 66 69 64 72 60 67 43 47 39 47 42 41 48 41 47 45 44 42 39 46 38 43 70 72 81 72 77 73 75 79 76 78 74 73 73 70 76 75 50 55 56 50 58 52 56 57 50 50 55 50 50 44 49 52 80 80 82 79 79 81 80 81 85 81 82 81 77 80 85 81 59 60 55 57 60 57 57 58 61 56 57 58 51 53 57 57 82 80 80 76 80 77 79 80 77 82 77 81 78 76 82 79 56 57 53 57 60 56 58 53 52 57 55 58 53 48 57 55 73 70 73 69 73 68 65 70 70 75 76 70 67 66 70 70 September Min 49 51 54 49 48 45 44 46 53 52 47 49 47 44 46 48 Year 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 15-yr. avg. 6-Month Average Max 6-Month Average Min 74 73 76 73 74 70 70 71 75 72 71 71 69 70 70 72 49 45 48 48 51 48 49 48 50 49 49 48 46 44 46 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 June July August September Total 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 15-yr. avg. 3.33 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 2.69 3.65 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 2.81 6.18 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 3.71 2.63 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 2.50 1.79 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 4.28 0.58 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 3.49 18.16 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 19.48 FERTILIZERS USED The previous crop was alfalfa which was plowed down in the spring of 1983. 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 0-0-60 200 lbs/A banded at planting 20-10-10 500 lbs/A sidedress prior to hilling 46-0-0 125 lbs/A sidedress at hilling 46-0-0 125 Ibs/A HERBICIDES Early preemergence alachlor (Lasso) at 2 lbs/A followed by a delayed preemergence application of metribuzin (Lexone) at lb/A. INSECT AND DISEASE CONTROL Temik was applied at planting at 3 lbs/A. The foliar fungicide applications were initiated on July 13 with 8 applications of Bravo. Foliar insecticides used were Pydrin on July 1, 25, and August 2 and Cygon on August 25. Diquat at 1 1/2 pints/A + X77 at 8 ounces per 100 gallons was used as a topkiller. 1983-MICHIGAN POTATO Variety EVALUATIONS R.W. Chase, R.B. Kitchen, R. Vander Zaag, R. leep, and R. Hammerschmidt Department of Crop and Soil Sciences and Botany and Plant Pathology A. DATES OF HARVEST The 1983 dates-of-harvest study was conducted at the Montcalm Research Farm. Three complete plantings and four replications of all varieties were made on May 4 in individual plots 10 feet x 34 inches. Plant spacing within the row was 12 inches. The previous crop was alfalfa and 250 lbs/A of 0-0-60 were plowed down, 500 lbs/A of 20-10-10 were applied with the planter, and two sidedress applications of 46-0-0 at 150 lbs/A each were applied in June prior to hilling. Aldicarb (Temik 15G) was applied at 20 lbs/A at planting. Alachlor (Lasso) was applied at early preemergence at 2 lbs/A and metribuzin (Lexone) at lb/A at delayed preemergence. The plots were irrigated 17 times and foliar insecticides and fungicides were applied as needed. The weather stress was very severe in 1983 with cool and wet soil conditions at planting followed by slow emergence and early growth. This was followed by extremely hot and dry weather throughout most of the growing season. Total rainfall April through September was 19.11 inches which is very comparable to the 15 year average, however, rainfall during June, July, and August was only 5.84 inches or about 50% of normal. Average maximum temperatures were substantially above normal during this same period. There were 14 days with temperatures about 90° F and there were many nights that temperatures did not drop below 70° F. Results: Table 1 summarizes the yields, size distribution, and specific gravity of the several cultivars at each harvest. Average yields on August 9 were well below the normal average with only 74% U.S. No. 1 size. The severe weather caused below normal performance of several varieties. Individual varieties such as Shepody, Ontario, and Russet Burbank were substantially below 60 cwt/A of marketable potatoes. Average total yields increased by 71% by August 31 harvest and the yield of U.S. No. 1 (marketable size) increased by 95% which reflects the fact that tuber sizing for many varieties was delayed. Even at the late harvest several varieties still had a high percentage of tubers under two inches. Table 2 summarizes the internal defects, chip ratings, and black spot damage. Vascular discolorations were fairly prevalent, however, these were predominately classed as slight and would not cause any market problem. Those noted as severe would clearly show in a processed potato chip, however. Internal necrosis was minimal and hollow heart was not as severe as anticipated. Chip scores except for Onaway and Ontario were all rated as very good. Table 3 summarizes the after-cooking-darkening ratings which were determined on December 7 after storage at 52° F. Varieties which showed the greatest degree of darkening were Ontario and Snowchip. Several selections showed increased darkening as the tubers were allowed to cool which is not desirable from a consumers standpoint. Variety Observations: Atlantic - Yielded above average at all harvest dates with high specific gravity, excellent chip quality, and no after cooking darkening was observed. Tubers do slough after boiling because of high dry matter. Chipbelle - Yielded below the average at each harvest and highest in specific gravity. Jemseg - An early maturing variety that sets and sizes tubers early. Second highest yielder at 97 day harvest but still substantially below Onaway. Variety tends to have a light set which contributes to larger sizing. Specific gravity and chip quality is better than Onaway. Foliage showed severe wilt-type early dying. Katahdin - A late maturing variety which sized tubers well by the third harvest. Onaway - The highest yield at both the first and second harvests and no internal defects. Ontario - Very late maturity as evidenced by the poor sizing. High percentage of pick outs due to second growth and heat sprout. Considerable after cooking darkening. Russet Burbank - Very poor sizing and high percentage of pick outs. Hollow heart noted at both the second and third harvests. Shepody - Late maturing and a high percent of pick outs, mostly off-type and growth crack. Some scab noted. A long, white with higher specific gravity than Russet Burbank. Processes well for frozen french fries. May be susceptible to mosaic virus in foliage. Snowchip - Late maturing and highest yield at 142 day harvest. Higher marketable yield than Ontario with less pick outs. Similar to Ontario in after cooking darkening at two hours after cooling. Some severe vascular discoloration noted. Yukon Gold - Medium maturity, golden flesh, and susceptible to scab. Tubers sized well. Optimum marketable yield in 115 days. MS700-79 - Medium maturity with below average yields. No internal defects and chips well out of field. May have susceptibility to virus-mosaics. MS700-83 - Medium-late maturity and above average yields. Round white, uniform appearance with minimal internal defects. Good chips out of field and no after-cooking-darkening. Yielded well in Presque Isle County demonstration plot and highest specific gravity. Also yielded above average in Bay County harvest August 17. MS701-22 - Medium-late maturity, round white with below average yields. MS702-80 - Round white, medium maturity, and medium specific gravity. Minimal internal defects and good chip quality. Some scab tolerance. MS702-91 - Late maturing, round to oblong, white with yields substantially above average. Some internal necrosis and hollow heart noted. Good culinary qualities. MS704-10 - Medium maturity, round, golden flesh cultivar with high specific gravity. Minimal internal defects and good chip color. MS704-17 - Medium-late maturity with high yields. Round white with susceptibility to scab. MS714-10 - Medium maturity with average yields. Oblong in shape and medium specific gravity. Some hollow heart noted. MS716-15 - Medium maturing, round white with average yields, and high specific gravity. MS718-6 - Medium-late maturity with average yields. Some after cooking darkening noted. B7154-10 - Being deleted because of serious growth cracks and low specific gravity. B7805-1 - Being deleted because of poor stands at all locations and below average yields. B9540-62 - An oblong to long russet from the USDA-Beltsville breeding program. Low yields and specific gravity and poor tuber sizing as evidenced by high percentage of B size tubers. Some after-cooking-darkening after cooked tubers were allowed to cool. C-13 - A medium-early selection from the Campbell breeding program. The yield performance was lower than normal and growth crack was more prevalent than usual. Table 1. Yield, size distribution, and specific gravity of several potato varieties harvested on three different dates in Michigan. 1983. August 31 (119 Days)Percent Size Distribution <2" August 31 (119 Days) Percent Size Distribution 2-3 1/4 August 31 (119 Days) Percent Size Distribution >3 1/4 August 31 September (119 Days)Percent Size Distribution Pick Outs August 31 (119 Days) Specific Gravity September 23 (142 Days)Yield cwt/ATotal 23 (142 Days) Yield cwt/ANo. 1 September 23 (142 Days) Percent Size Distribution <2" September 23 (142 Days)Percent Size Distribution 2-3 1/4 September 23 (142 Days)Percent Size Distribution >3 1/4 September 23 (142 Days)Percent Size Distribution Pick Outs September 23 (142 Days) Specific Gravity empty table cell empty table cell empty table cell empty table cell August 9 (97 Days) Percent Size Distribution<2" August 9 (97 Days) Percent Size Distribution 2-3 1/4 August 9 (97 Days) Percent Size Distribution >3 1/4 August 9 (97 Days) Yield cwt/ATotal August 9 (97 Days) Yield cwt/ANo. 1 August 9 (97 Days)Percent Size DistributionPick Outs August 9 (97 Days) Specific Gravity August 31 (119 Days) Yield cwt/ATotal August 31 (119 Days) Yield cwt/ANo. 1 247 262 410 272 281 106 45 264 183 137 233 143 302 191 210 233 254 276 237 202 318 206 185 216 226 168 167 370 204 243 56 8 199 133 52 158 106 205 114 143 150 199 218 203 171 289 172 143 143 167 30 34 9 23 13 47 82 24 27 58 32 26 32 40 30 35 20 20 13 14 9 16 23 34 66 64 76 71 74 53 18 75 73 38 66 74 67 60 68 64 73 75 82 83 79 82 75 64 2 0 14 4 12 0 0 0 0 0 2 0 1 0 0 0 6 4 3 2 12 2 2 2 2 2 1 2 1 0 0 1 0 4 0 0 1 0 2 1 2 1 2 1 0 1 0 0 1.067 1.075 1.067 1.078 1.077 1.075 1.063 1.088 1.064 1.072 1.090 1.075 1.085 1.077 1.084 1.074 1.078 1.062 1.077 1.084 1.075 1.068 1.078 1.071 empty table cell empty table cell empty table cell empty table cell 1.075 420 462 578 467 522 377 189 418 406 422 379 341 425 410 362 370 391 404 354 345 337 304 291 297 386 349 409 515 412 508 202 77 373 366 187 325 308 381 341 306 319 349 349 326 322 321 274 260 230 325 Variety Snowchip MS-702-91 Onaway MS-700-83 MS-704-17 Shepody Ontario Atlantic Katahdin R. Burbank MS-716-15 MS-718-6 MS-704-10 MS-714-10 Chipbelle MS-702-80 Yukon Gold B-7154-10 C-13 MS-700-79 Jemseg B-7805-1 MS-701-22 B-9540-62 AVERAGE 15 12 7 11 2 16 37 11 10 31 14 10 11 17 13 14 11 11 6 7 4 9 10 23 75 85 69 73 59 49 41 85 72 43 72 77 80 77 72 80 75 76 79 78 74 81 78 66 2 0 4 1 0 30 23 0 0 25 0 0 0 0 3 0 0 3 2 0 0 1 1 0 8 4 20 15 38 5 0 5 18 1 14 13 10 6 13 6 14 10 13 15 22 10 11 12 empty table cell 1.074 1.078 1.066 1.080 1.077 1.077 1.061 1.089 1.069 1.077 1.089 1.078 1.085 1.078 1.094 1.075 1.079 1.062 1.075 1.085 1.070 1.069 1.082 1.072 empty table cell 1.077 584 534 532 501 494 492 475 432 419 417 407 396 392 388 373 371 346 342 331 313 302 296 282 248 403 484 475 505 450 469 321 302 375 380 171 357 369 340 313 304 317 303 273 286 282 279 258 252 181 335 71 78 76 70 60 44 61 82 72 40 78 63 81 70 82 80 75 74 78 73 82 68 80 68 15 10 5 10 5 11 17 13 9 30 12 6 13 18 17 15 12 14 11 10 7 10 11 27 empty table cell 13 11 20 20 35 21 3 5 19 1 10 31 5 11 0 5 13 6 9 17 10 20 10 5 2 1 0 0 0 24 19 0 0 29 0 1 0 2 2 0 0 6 2 0 1 3 0 0 1.071 1.076 1.065 1.078 1.073 1.080 1.070 1.090 1.067 1.075 1.087 1.078 1.083 1.073 1.093 1.074 1.076 1.058 1.070 1.082 1.066 1.068 1.079 1.069 empty table cell 1.075 Table 2. Internal defects1, chip scores, and bruising damage of several potato varieties in Michigan. 1983. August 31 August 31 Harvest August 31 August 31 HarvestVAS DIS Harvest INT NEC H H Harvest Chip2 Score August 31 Harvest %3 Bruise Free September 23 September 23 Harvest September 23 September 23 Harvest September 23 HarvestVAS DIS Harvest INT NEC H H Harvest Chip2 Score %3 Bruise Free 3 sl 2 sl 2 sl 5 sl 3 sl 3 sl 0 4 sl 3 sl 1 sev 3 sl 0 0 0 0 7 sl 0 2 sl 1 sl 1 sl 1 sl 5 sl 1 sl 5 sl 3 sl 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 1 1 0 0 0 0 0 0 1 0 0 0 0 3 0 1 0 0 1.0 1.0 1.5 1.5 3.0 3.0 2.0 2.0 1.5 1.5 1.0 1.0 1.0 1.0 1.0 1.0 1.5 1.5 1.0 1.0 1.0 1.5 1.5 1.0 94 66 86 66 87 — 72 100 81 82 60 74 43 88 87 76 67 67 76 50 — — 90 80 3 sl 6 sl 2 sev 4 sl 7 sl 3 sev 5 sl 0 5 sl 3 sl 7 sl 4 sev 8 sl 0 2 sl 0 0 0 1 sl 3 sl 0 4 sl 8 sl — — 10 sl 7 sl 0 0 0 0 0 0 0 0 1 0 0 0 0 0 2 0 0 0 0 0 — — 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 2 0 2 — — 0 1 1.0 1.0 2.0 1.5 3.5 3.0 2.0 2.0 1.5 2.0 1.0 1.5 1.5 1.0 1.5 1.5 1.5 2.0 1.0 1.5 — — 1.0 1.5 90 95 89 87 95 — 88 92 96 93 83 86 86 93 85 84 80 95 92 89 — — 80 - Variety Atlantic Chipbelle Jemseg Katahdin Onaway Ontario R. Burbank Shepody Snowchip Yukon Gold MS700-79 MS 700-83 MS701-22 MS702-80 MS702-91 MS704-10 MS704-17 MS714-10 MS716-15 MS718-6 B7154-10 B7805-1 B9540-62 C-13 1 20 tubers cut to determine internal defects. VAS DIS = vascular discoloration; INT NEC = internal necrosis; H H = hollow heart, sl = slight, sev = severe. 2Chip score based on PC/SFA 1-5 scale. 1 = lightest, 5 = dark, not acceptable. 3Bruising evaluation run by Ore-Ida; damage noted primarily as black spot which is determined after peeling. Table 3. Determinations of after-cooking-darkening of several potato cultivars. empty table cell Atlantic Chipbelle Jemseg Katahdin Onaway Ontario Russet Burbank Shepody Snowchip Yukon Gold MS700-79 MS 700-83 MS701-22 MS702-80 MS702-91 MS 704-10 MS704-17 MS714-10 MS716-15 MS718-6 B9540-62 C-13 After Cooking Darkening1 After Cooking Darkening1 0 Hours 2 Hours 1.0 2.0 1.5 1.5 1.5 1.5 1.0 1.0 1.5 1.0 1.5 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.5 1.0 1.0 1.0 2.0 2.5 2.5 2.0 3.5 1.0 1.0 3.5 1.0 2.0 1.5 1.5 1.0 1.5 1.5 1.5 1.0 1.0 2.5 2.5 1.0 1 Samples stored 75 days at 52° F. Tubers peeled and sliced in half from stem end to apical end. Samples steam boiled for 35 minutes. Readings made at completion of boiling and at two hours after tubers were cooled. 1 = light with no darkening; 5 - overall gray to black darkening. B. USDA-BELTSVILLE TRIALS Four separate trials evaluating selections from the USDA-Beltsville potato breeding program were conducted in 1983. Cultural, fertility, and management practices used were the same as described in the dates of harvest study. Two studies were with russet and round white selections made from the Chapman Farm (Presque Isle, Maine) seed plot harvests in September, 1982. Two studies (russets and whites) were inter-regional trials conducted in conjunction with several other states. Tables 4 and 5 summarize the yield data obtained from the 1982 Chapman Farm selections. Tuber sizing was limited as evidenced by the high percentage of tubers under 2” and the low percentage of tubers over 31/4” diameter. In terms of overall performance no selections were judged to be better than Atlantic. Selections B8682-4, B9769-18, and B9792-9 will be tested again in 1984. Sizing of the russet selections was very poor and specific gravity readings were below 1.075, a minimum level desired in long russets in Michigan. All selections, however, were substantially better than Russet Burbank in terms of pick outs and off type tubers. Selections B9752-7 and B9400-5 will be tested again in 1984. Tables 6 and 7 summarize the yield data for the round whites and russets in the USDA-Beltsville inter-regional trial. All round-white selections yielded less than Atlantic and specific gravity readings were lower also. Foliar maturities for both the round-whites and russets were noted as medium- early to medium. The latest maturing selections as noted on August 20 were B8706-7 and G670-11 and comparable to Kennebec, Atlantic, and Russet Burbank. Hollow heart was noted in only Kennebec and G670-11 and no internal necrosis was noted. Considerable jelly end rot was noted on B9596-2. Table 8 summarizes the yield data for the 13 cultivars which were selected at harvest from the approximately 225 eight hill plantings from the USDA-Beltsville seedlings. Four selections were deleted after harvest from further testing because of low specific gravity and severe vascular discoloration in B8687-8. Table 4. Yield, size distribution, and specific gravity of several round white selections from the USDA-Beltsville breeding program. Yield cwt/A Yield cwt/A Percent Size Distribution Percent Size Distribution Percent Size Distribution Cultivar Total No. 1 <2" 2-3 1/4 >3 1/4 Percent Size Distribution Pick Outs Specific Gravity 70 82 74 87 76 82 59 80 70 77 82 91 2 8 7 3 3 9 0 6 7 0 5 4 3 0 1 1 0 1 0 1 2 2 4 0 1.066 1.087 1.076 1.065 1.062 1.073 1.077 1.064 1.069 1.079 1.069 1.078 1.072 B9769-18 Atlantic B8682-4 B8702-18 B8687-3 B9792-9 B9539-9 B8687-13 B9510-5 B9527-1 Superior B9516-8 AVERAGE 605 490 490 429 423 396 365 342 329 302 300 219 391 432 438 394 388 338 359 215 292 252 233 260 206 317 26 11 19 9 21 9 41 14 23 22 10 6 empty table cellempty table cellempty table cellempty table cell Planted May 6; Harvested September 12, 1983. Table 5. Yield, size distribution, and specific gravity of several russet selections from the USDA-Beltsville breeding program. Yield Yield Percent Size Percent Size Distribution Percent Size Distribution Percent Cultivar cwt/A Total cwt/A No. 1 Distribution<2" 2-3 1/4 >3 1/4 Size Distribution Pick Outs Specific Gravity B9752-7 B9400-5 R. Burbank B9729-6 B9740-1 B9569-2 B9738-2 B9752-3 AVERAGE 503 475 444 327 321 300 300 263 366 411 388 209 200 235 194 169 119 240 18 15 23 40 26 36 42 46 61 43 43 58 64 58 54 44 21 40 5 2 9 7 3 2 2 3 30 0 1 0 2 9 empty table cellempty table cellempty table cellempty table cell 1.068 1.069 1.071 1.070 1.062 1.065 1.068 1.066 1.067 Planted May 6; Harvested September 12, 1983. Table 6. Yield, size distribution, and specific gravity of several round white cultivars. Inter-regional trial. Yield cwt/A Yield Percent Size Distribution Percent Size Distribution Percent Size Distribution Percent Size Cultivar Total cwt/A No. 1 <2" 2-3 1/4 >3 1/4 Distribution Pick Outs Specific Gravity Chip2 Scores Atlantic B8091-8 G670-11 1 B8706-7 Onaway B9340-13 B9384-4 B9140-32 B9224-6 Kennebec 1 Superior B9192-1 AVERAGE 364 339 327 314 304 293 291 276 262 241 239 233 290 324 289 277 281 262 250 204 241 227 175 212 214 246 11 15 10 9 12 15 30 13 13 20 7 8 85 82 76 80 75 85 70 87 82 69 82 88 empty table cell empty table cellempty table cell empty table cell 4 3 8 10 12 0 0 0 5 4 6 3 0 0 5 2 3 0 0 0 0 8 4 0 1.079 1.073 1.075 1.065 1.057 1.072 1.066 1.077 1.061 1.059 1.059 1.060 1.067 1.5 2.0 2.5 1.5 3.5 2.0 1.0 1.0 1.5 2.0 2.0 1.5 empty table cell Planted May 6; Harvested September 15, 1983. 1Selections from University of Guelph, Ontario Canada. 2 Samples processed October 19. PC/SFA scale; 1 = lightest, 5 = dark and unacceptable. Table 7. Yield, size distribution, and specific gravity of several russet cultivars. Inter-regional trial. Yield Yield Percent Size Percent Size Distribution Percent Size Distribution Percent Size Cultivar cwt/A Total cwt/A No. 1 Distribution <4 oz B9553-6 Belrus B9398-2 R. Burbank B9648-9 B9596-2 B9523-10 B9540-62 Gold Rus 476 318 302 298 275 270 231 222 191 372 167 173 66 143 141 121 112 87 17 46 40 38 46 36 41 44 51 4-10 oz 62 50 51 22 51 45 51 49 46 >10 oz 17 3 6 0 1 7 2 2 0 5 1 3 40 3 12 6 5 3 AVERAGE 287 153 empty table cell empty table cell empty table cell empty table cell1.064 empty table cell Planted May 6; Harvested September 2, 1983. Distribution Pick Outs Specific Gravity Comments 1.065 Severe heat sprout 1.074 empty table cell 1.073 empty table cell empty table cell 1.065 1.056 1.058 1.055 1.062 1.068 Dark russet 25% jelly end rot Some growth crack Some vascular discoloration Some growth crack and vascular discoloration Table 8. Yield, size distribution, and specific gravity of several cultivars selected at harvest from eight-hill plantings of USDA-Beltsville selections. Yield cwt/A cwt/A Yield Percent Size Percent Size Distribution Percent Size Cultivar Total No. 1 Distribution<2" 2-3 1/4 Distribution>3 1/4 Specific Gravity Comments B8687-8 B8687-10 B8751-6 B9541-45 B9581-10 B9638-11 B9718-2 B9792-6 B9792-84 B9792-111 B9792-119 B9792-191 B9922-11 404 471 538 384 461 452 404 461 576 557 500 470 461 336 413 452 375 413 336 221 403 499 481 471 432 375 17 13 16 3 10 25 45 13 13 14 6 8 19 83 77 79 83 79 72 48 77 80 79 77 84 56 0 10 5 14 11 3 7 10 7 7 17 8 25 1.076 1.071 1.079 1.070 1.075 1.084 1.063 1.086 1.085 1.089 1.081 1.069 1.082 Severe vascular discoloration- discarded Round, smooth Round, smooth slightly flattened Medium deep eyes-discarded Oval, medium eye depth, slight net Smooth, slightly flattened Russet, discarded- low specific gravity Round to oblong, deep eyes Slight net, deep eyes Deep eyes, some scab Deep eyes, slight net, some scab Discarded-low specific gravity Russet, oblong, slightly flat C. OVERSTATE DEMONSTRATION TRIALS Yield data were collected from two commercial farm locations in 1983. These were established as demonstration plantings and are not replicated plots. Plots were located at the Henry Mulders Farm in Munger and at the Wilks Farm in Posen. At the Mulders Farm the entire variety planting was harvested and graded and these data are reported in Table 9. Severe growth cracks were noted in B7154-10 and a very poor stand and heat sprout were noted with B7805-1. Both are being discontinued from any further testing in Michigan. At the Wilks Farm three 15 foot areas from each variety were harvested, graded, and averaged to determine yield performance which is summarized in Table 10. Superior, MS704-17, MS700-83, and C-13 were located in sprayer rows so their yield potential was likely reduced. Considerable pick outs was noted with Yukon Gold, Ontario, C-13, and Jemseg and this was primarily severe growth cracks, knobby tubers, second growth and tuber greening. MSU seedling 700-83 produced good yields with a minimum of grade outs. Table 9. The yield, size distribution, specific gravity, and chip quality of several potato varieties. Bay County, Henry Mulders Farm, Munger, Michigan. 1983. Percent Size Distribution Percent Size Distribution Percent Total (cwt/A) U.S. No. 1 (cwt/A) Size Distribution2-3 1/4" Over 3 1/4" Under 2" Percent Size DistributionPick Outs Specific Gravity Chip 1 Score 356 349 347 323 255 250 194 122 275 319 299 298 273 215 227 156 108 237 82 85 84 82 81 88 78 82 7 12 12 15 13 9 19 11 empty table cellempty table cell 3 2 3 1 3 0 0 0 empty table cell 8 1 1 3 4 3 2 7 1.070 1.065 1.061 1.072 1.072 1.073 1.066 1.058 1.5 2.0 1.5 1.0 1.5 1.0 1.0 1.5 empty table cell empty table cell 1.067 Variety Jemseg Onaway B7154-10 MS700-83 Yukon Gold Oceania C-13 B7805-1 average Planted April 27; Harvested August 15, 1983. 1PC/SFA scale; 1 = lightest, 5 - dark and unacceptable. Table 10. The yield, size distribution, and specific gravity of several potato varieties. Presque Isle County, Wilks Farms, Posen, Michigan. 1983. Percent Size Percent Size Distribution Percent Size Distribution Percent Size Distribution U.S. No. 1 Variety Total U.S.1 No. 1 U.S. No. 12-3 1/4 Over 3 1/4 Under 2" Distribution Pick 2 Outs Specific Gravity (cwt/A) (cwt/A) Katahdin Snowchip Yukon Gold 700-83 704-17 Onaway Ontario Superior Atlantic C-13 Jemseg AVERAGE 409 377 385 358 332 329 332 260 241 252 184 314 352 330 328 319 308 292 273 236 214 207 145 273 50 70 60 82 77 65 73 74 79 64 44 36 17 25 7 16 24 9 17 10 19 36 5 8 3 10 7 4 8 9 11 3 4 9 5 12 1 0 7 10 0 0 14 16 empty table cell empty table cell empty table cellempty table cell 1.068 1.076 1.077 1.084 1.078 1.066 1.070 1.075 1.083 1.075 1.068 1.075 Planted June 7; Harvested October 12, 1983. 1U.S. No. l’s consists of potatoes 2-3 1/4" plus those over 3 1/4". 2 Pick outs consisted mainly of growth cracks, knobs, irregular shape, and serious greening. EVALUATIONS OF CULTIVARS FOR FROZEN PROCESSING R.W. Chase, R.B. Kitchen, and R. Vander Zaag, MSU J. Fuller and R. Smoth, One-Ida Foods, Inc. Advanced seedlings from the USDA-Aberdeen, Idaho potato breeding program were evaluated for early and late harvests. Total yields, size distribution solids, external and internal defects, and percent sugars as determined by fry color were recorded. Seven selections for the early harvest were planted on May 5 and harvested on August 25. Six selections for the late harvest trial were also planted on May 5 and harvested on September 29. Seven selections from the 1982 8-hill screening were planted on May 5 and harvested on August 25 and 45 new 8-hill selections were planted for adaptability selection. RESULTS Table 1 summarizes the yield performance of the advanced, early variety evaluations. Table 1. ADVANCED EARLY VARIETY EVALUATIONS - ORE-IDA. Percent Size Distribution Under 4 oz. Percent Size Distribution 4-6 Percent Size Distribution 6-10 Percent Size Distribution Over 10 Percent Size DistributionNo. 2's HH/ No. Cut Specific Gravity Percent Solids Maturity Percent Sugars 1 Percent Sugars0 Percent Sugars 2Percent Sugars 3Percent Variety (cwt/A) Yield Yield (cwt/A) No. 1 Total A76147-2 Onaway A77155-4 A76260-16 A71991-5 Shepody A68678-9 Average 459 366 325 309 308 280 245 327 317 260 200 180 226 145 150 211 21 22 27 38 17 29 27 27 29 34 26 26 31 32 23 21 35 21 23 11 12 9 4 12 4 11 7 13 4 10 20 0/20 0/20 1/20 0/20 1/20 4/20 1.070 1.062 1.068 1.066 1.070 1.076 0/20 1.068 empty table cell1.069 18.6 16.9 18.1 17.6 18.5 19.8 18.0 18.2 Late 60 15 Med-Early 60 30 Med-Early 100 Med-Early Medium Late 100 100 95 0 0 0 5 10 10 0 0 0 0 0 0 0 0 0 0 Sugar Ends % Bruise Free % 5 0 0 0 0 15 06 80 80 76 83 75 Sugars4 15 0 0 0 0 0 37 26 empty table cell empty table cell empty table cell empty table cell 11 4 empty table cell V. Late 0 empty table cellempty table cell 0 empty table cell 0 empty table cell 0 empty table cell 83 empty table cell empty table cell 100 0 empty table cell A76147-2 - Emergence was noted to be very early with good vine growth and vigor. Maturity was rated as late. Yields were well above average, except tubers did not size as desired. At harvest, severe skinning and considerable growth crack were noted. Worthy of further testing. Onaway - Used as a reference variety, particularly for yield. It is not considered a processing potato. A77155-4 - Emergence was noted as being early with average vine growth and vigor. A trace of mosaic was noted. Maturity was med-early and similar to Onaway. Tuber appearance was noted as satisfactory, however, there was a high percentage of No. 2’s. Worthy of further testing. A76260-16 - Early emergence with a weaker type vine which appeared to show early senescence with wilt type symptoms. Considerable scab was noted on several tubers. Specific gravity was low, small size, and low score on bruising. Questionable for further testing. A71991-5 - Later in emergence with a small vine. Maturity was rated medium with severe wilt symptoms noted. Specific gravity average with good tuber sizing. At harvest, some tubers showed considerable growth crack. Questionable for further testing because of low yield. Shepody - Average in emergence and vine growth. Late maturity. Highest percentage of No. 2’s and hollow heart. Highest specific gravity. May be a better producer with reduced irrigation. Acreage grown in Canada is primarily not irrigated. At harvest, growth cracks and scab were severe. Suggest evaluation for one more year. A68678-9 - Average in emergence and vine growth. Trace of mosaic. Very late maturity. Suggest discontinuing because of lateness and low yield. Table 2 summarized the performance of the advanced, late maturity varieties. Table 2. ADVANCED LATE VARIETY EVALUATIONS- ORE-IDA, 1983 Variety A76147-2 A76147-2 A76147-2 A76147-2 A76147-2 A76147-2 A72685-2 A72685-2 A72685-2 A72685-2 Shepody Shepody Shepody Shepody Yield (cwt/A) Total empty table cell empty table cell empty table cell empty table cell empty table cell empty table cell empty table cell empty table cell empty table cell empty table cell empty table cell 580 358 341 323 312 A7411-2 empty table cell A7411-2 empty table cell A7411-2 empty table cell A7411-2 R. Burbank R. Burbankempty table cell R. Burbankempty table cell R. Burbankempty table cell A7668-2 A7668-2 A7668-2 A7668-2 empty table cell empty table cell empty table cell 271 Percent Size Distribution Percent Size Distribution No.2’s 15 empty table cell empty table cell empty table cell empty table cell empty table cell Percent Size Distribution Percent Size Distribution 4-6 Percent Size Distribution 6-10 Yield (cwt/A)No. 1 199 424 240 Under 4 oz. 12 empty table cell empty table cell empty table cell empty table cell empty table cell 29 empty table cell empty table cell empty table cell 17 empty table cell empty table cell empty table cell 18 empty table cell empty table cell empty table cell 46 empty table cell empty table cell empty table cell 41 empty table cell empty table cell empty table cell 18 empty table cell empty table cell empty table cell empty table cell empty table cell 24 empty table cell empty table cell empty table cell 19 empty table cell empty table cell empty table cell 18 empty table cell empty table cell empty table cell 21 empty table cell empty table cell empty table cell 27 empty table cell empty table cell empty table cell Over 10 21 empty table cell empty table cell empty table cell empty table cell empty table cell 16 empty table cell empty table cell empty table cell 14 empty table cell empty table cell empty table cell 24 empty table cell empty table cell empty table cell 3 empty table cell empty table cell empty table cell 5 empty table cell empty table cell empty table cell 35 empty table cell empty table cell empty table cell empty table cell empty table cell 27 empty table cell empty table cell empty table cell 24 empty table cell empty table cell empty table cell 25 empty table cell empty table cell empty table cell 14 empty table cell empty table cell empty table cell 23 empty table cell empty table cell empty table cell 215 120 149 Bruise Free % 87 5 19.3 late 2/40 Maturity 18/40 V. Late HH/ No. Cut 0/40 Dry Matter 18.1 Plot No. 102 empty table cellempty table cellempty table cellempty table cellempty table cell 102 empty table cellempty table cellempty table cellempty table cellempty table cell 203 empty table cellempty table cellempty table cellempty table cellempty table cell 303 empty table cellempty table cellempty table cellempty table cellempty table cell 402 empty table cellempty table cellempty table cellempty table cellempty table cell 402 101 empty table cellempty table cellempty table cellempty table cellempty table cell 205 empty table cellempty table cellempty table cellempty table cellempty table cell 302 empty table cellempty table cellempty table cellempty table cellempty table cell 404 106 empty table cellempty table cellempty table cellempty table cellempty table cell 204 empty table cellempty table cellempty table cellempty table cellempty table cell 304 empty table cellempty table cellempty table cellempty table cellempty table cell 401 103 empty table cellempty table cellempty table cellempty table cellempty table cell 201 empty table cellempty table cellempty table cellempty table cellempty table cell 301 empty table cellempty table cellempty table cellempty table cellempty table cell 406 105 empty table cellempty table cellempty table cellempty table cellempty table cell 202 empty table cellempty table cellempty table cellempty table cellempty table cell 306 empty table cellempty table cellempty table cellempty table cellempty table cell 405 104 empty table cellempty table cellempty table cellempty table cellempty table cell 206 empty table cellempty table cellempty table cellempty table cellempty table cell 305 empty table cellempty table cellempty table cellempty table cellempty table cell 403 V. late V. Late 11/40 4/40 3/40 Late 21.3 late 19.2 63 97 87 96 76 18.1 19.1 5 empty table cell empty table cell empty table cell 25 empty table cell empty table cell empty table cell 17 empty table cell empty table cell empty table cell 16 empty table cell empty table cell empty table cell empty table cell empty table cell empty table cell Natural Sugars 3Natural Sugars Natural Sugars 1 4 Natural Sugars 0 100 0 0 90 0 15 90 0 0 0 90 15 70 0 30 100 0 0 0 85 0 80 0 5 10 90 0 90 5 0 100 0 0 100 0 0 100 0 0 100 0 0 100 0 0 100 0 0 100 0 0 100 0 0 100 0 0 missingmissingmissing 75 0 0 90 0 10 100 0 0 100 0 0 100 0 0 100 0 0 0 0 10 0 0 0 15 15 0 0 0 0 0 0 0 0 0 0 0 missingmissingmissing 5 0 0 0 0 0 Natural Sugars 2 0 0 0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Natural SugarsSF 15 20 15 20 25 20 20 15 20 0 20 10 20 5 0 0 0 0 35 40 20 10 5 20 15 A76147-2 A72685-2 - Very good yields and sizing and free of hollow heart. Good early emergence and vigorous vine growth. Good tuber type, however, growth cracks were severe in some cases. Worthy of testing in 1984. - Early emergence with average vine growth. Very late maturity and severe hollow heart. Poor tuber sizing and also lower score on bruise test. Concern for lateness of maturity for Michigan conditions. Shepody - Similar results as in early trial. Considerable external tuber defects. Suggest evaluation for one more year. A7411-2 - Early emergence, however, vine growth was noted as irregular. Very late maturity and highest solids. Some growth crack and scab noted. Tuber type was noted as above average overall. Suggest testing again in 1984. R. Burbank - Very poor sizing and type in 1983. A7668-2 - Average emergence with subsequent good vigor and vine type. Trace of mosaic. Very late maturity and tuber shape is oblong to round. Low yields and severe hollow heart. Questionable for further testing because of low yield, lateness, and poor tuber sizing. Table 3 shows the results of the preliminary variety trials. These selections were made from the 1982 8-hill observation trials. Table 3. PRELIMINARY VARIETY EVALUATIONS - ORE-IDA. Variety Yield (cwt/A) Total Yield (cwt/A) No. 1 Percent Size Distribution Under 4 oz. Percent Size Distribution 4-6 Percent Size Distribution Percent Size Distribution 6-10 Over 10 Percent Size Distribution No. 2's HH/ No. Cut Matter Dry % Bruise Free % Plot No. Natural Sugars Natural Sugars Natural Sugars 0 1 2 Natural Sugars Natural Sugars 3 4 SF Natural Sugars A77629-7 A77629-7 A78242-5 A78242-5 A7854-6 A7854-6 R. Burbank R. Burbank Onaway Onaway A7876-1 A7876-1 A7532-1 A7532-1 550 413 empty table cell empty table cell 11 32 empty table cellempty table cell 35 empty table cell 103 empty table cellempty table cellempty table cell empty table cellempty table cell 201 17.5 8/20 62 14 10 518 431 empty table cell empty table cell 8 31 empty table cellempty table cell 41 empty table cell 12 empty table cell empty table cell 17 33 empty table cellempty table cell 21 empty table cell 17 empty table cell empty table cell 42 16 empty table cellempty table cell 5 empty table cell 22 344 268 empty table cell empty table cell 22 34 empty table cellempty table cell 20 empty table cell 24 empty table cell empty table cell 42 23 empty table cellempty table cell 14 empty table cell 18 10 0/20 76 81 13 19.0 7/20 18.4 105 empty table cellempty table cellempty table cell empty table cellempty table cell 202 101 empty table cellempty table cellempty table cell empty table cellempty table cell 205 107 empty table cellempty table cellempty table cell empty table cellempty table cell 203 106 empty table cellempty table cellempty table cell empty table cellempty table cell 204 104 empty table cellempty table cellempty table cell empty table cellempty table cell 206 16/20 4/20 18.4 18.8 0/20 17.1 100 90 17 --- 1 4 450 371 282 231 314 154 154 129 40 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 10 0 100 missing missing missing missing missing missing 100 100 100 100 100 100 95 50 90 80 5 5 20 15 15 20 0 0 5 30 5 15 0 0 0 40 5 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 empty table cell empty table cell 42 19 empty table cellempty table cell 5 empty table cell 102 empty table cellempty table cellempty table cell empty table cellempty table cell 207 18.8 2/20 81 32 3 100 100 0 0 0 0 A77629-7 - Emergence and vine growth were average with late maturity. Size distribution was desirable with a high percentage of large tubers, however, they were generally rough. Continuation questionable because of rough tubers, lower solids, and hollow heart. A78242-5 - Very quick emergence and good vine growth and vigor. Three mosaic plants were noted. Size distribution, solids, and freedom from hollow heart were all very desirable. Tubers were generally smooth with only a trace of scab. Worthy of evaluation in 1984. A7854-6 - Emergence and vine growth were below average. Tubers were badly skinned at harvest and hollow heart was substantial. Questionable for 1984 evaluation because of hollow heart and lateness. R. Burbank - Very poor tuber sizing even though emergence and early growth appeared above average. Onaway - Used as a reference variety primarily for yield. A7876-1 - Poor tuber sizing and severe hollow heart and growth crack. Discard from further tests. A7532-1 - Emergence and early growth noted as below average. Rugose and mild mosaic both present. Some growth crack at harvest. Suggest deletion because of poor yields. THE EFFECT OF CHLORINE WASH SOLUTIONS ON CUT SEED POTATOES R. Vander Zaag, R.W. Chase, R. Hammerschmidt, and R. Kitchen Department of Crop and Soil Sciences and Botany and Plant Pathology Chlorine wash treatments have been used on cut seed potatoes on several Michigan potato farms. Chlorine is an alternative to conventional seed treatments due to its reduced cost, the elimination of dusts in the air, and the resulting cleaner seed and planter. However, questions as to its specific effect on cut seed remain unanswered. Objectives 1. To determine the effect of different rates of chlorine on suberization. 2. To determine the optimum rate for chlorine wash solutions. 3. To compare the effectiveness of chlorine as a seed treatment alternative. 4. To determine the effect of various post-treatment storage conditions on chlorine treated seed. Laboratory Studies Initially, a microscope study was performed to determine the effect of different rates of chlorine on suberin layer formation. Five days after treating cut tubers with chlorine (Table 1), thin sections were made perpendicular to the cut surface. These sections were stained and the thickness of the suberin layer was measured under a microscope. As reported in previous studies, increasing rates of chlorine produced a thicker suberin layer. Table 1. Effect of different rates of chlorine on the thickness of suberin layer formation, as measured using staining techniques. Chlorine Rate Suberin Layer Thickness 100 ppm Cl 500 ppm Cl 1000 ppm Cl 5000 ppm Cl 10.9 13.2 13.4 23.4 A weight-loss method was used to evaluate the effect of different rates of chlorine on suberization. Using a cork borer, uniformly sized cylinders of tuber tissue were cut from Russet Burbank tubers. Each cylinder was dipped for 10 seconds in chlorine (Figure 1) and then allowed to suberize for either 5 or 11 days. The cylinders were weighed before and after drying for 3 hours in an oven at 95-105°F, and the percent weight lost was calculated. The amount of weight (water) lost during drying should be inversely proportional to the degree of suberin layer development, a thicker suberin layer reducing water loss. The results (Figure 1) indicate the cylinders treated with increasing chlorine rates lost more weight (water) during drying than those treated with water or low rates of chlorine. This indicates that the high chlorine rates produced a less effective water-vapor barrier (suberin layer). This retardation was evident even after 11 days of suberization. The ability of the suberin layer of chlorine-treated tuber tissue to resist invasion by the dry rot fungus Fusarium roseum was investigated. Disks of tuber tissue were cut from Russet Burbank tubers using a cork borer, and dipped in a chlorine solution (Figure 2). After the disks were suberized for various periods of time ranging from 2 hours to 8 days, 0.1 ml of water containing Fusarium spores was placed on each disk. After 5 days the disks were rated for extent of decay (1 = 0-5% of disk decayed, 5 = 75-100% decay). The results (Figure 2) show, for disks suberized 2 hours after treatment, increasing rates of chlorine caused more Fusarium decay than the lower chlorine rates, water, or no treatment. As the suberization period increased, the difference between the high and low chlorine rates became less. After 8 days of suberization, all treatments had essentially no decay, except for disks treated with the highest rates of chlorine. These results suggest high chlorine rates delay suberization, but do not permanently impair it. Contrary to anatomical observations of cut tubers which show that increasing chlorine rates cause thicker suberin layer formation, it appears that they cause a less effective water vapor and pathogen barrier to develop. These physiological measurements of the degree of suberin layer formation are undoubtly more important than anatomical measurements. However, low chlorine concentrations, such as might be used in seed-washing treatments, show no adverse effect when compared to no treatment. Field Experiments Two field experiments examining chlorine wash treatments were performed during the 1983 growing season. In these experiments, the chlorine wash treatments were applied using a spray nozzle, as cut seed passed under it on a conveyor. Figure 1. Percent weight lost during drying by cylinders of tuber tissue treated with different rates of chlorine. Cylinders were suberized 5 or 11 days before drying. Treatments with the same letter are not significantly different. Figure 2. Decay ratings of tuber disks treated with different rates of chlorine. After suber­ ization, a drop of water containing Fusarium spores was placed on each disk. 1 = 0-5% decay, 5 = 75-100% decay. Treatments with the same letter are not significantly different. Field Experiment #1 This study was performed in cooperation with Crooks Potato Farms, Montcalm County, and evaluated the effect of 4 seed treatments and several post­ treatment storage conditions on seed performance. The grower provided the larger quantities (approximately 100 lbs) of cut Monona seed required to simulate the different storage conditions. One of 4 seed treatments was applied at the back of the seed cutter: a) no treatment, b) water wash, c) 2400 ppm Cl wash, and d) captan-streptomycin dust (3/4 lb/100 lbs seed). Treated seed was then given one of nine storage treatments: a) plant treated seed within 4 hours. b) hold seed 2 days at 52°F with good ventilation. c) hold seed 2 days at 52°F with poor ventilation. d) hold seed 2 days at ambient air temp. with good ventilation. e) hold seed 2 days at ambient air temp. with poor ventilation. f) hold seed 5 days at 52°F with good ventilation. g) hold seed 5 days at 52°F with poor ventilation. h) hold seed 5 days at ambient air temp. with good ventilation. i) hold seed 5 days at ambient air temp. with poor ventilation. The good and poor ventilation treatments were achieved by storing seed in an open or plastic-wrapped burlap bag, respectively. The ambient air temperature treatment involved storing seed in an uninsulated shed and allowing the air temperature to follow daily fluctuations. Seed was planted May 13-16 in 10' x 34" plots with four replications, and standard cultural practices were followed. Plots were harvested September 15. Results After storage, untreated seed stored 5 days at ambient air temperature with poor ventilation had 13% rotted seed pieces and was the only treatment in which storage decay was observed. Both the chlorine wash and captan-streptomycin seed treatments produced better stands and yield than untreated seed (Figure 3 and 4). There was no significant difference in stand or yield between the water or chlorine wash treatments, suggesting the washing action of the water is at least partially responsible for the beneficial effect on seed performance of the chlorine treatment. Storage conditions appeared to have no effect on stand (Table 2). The only observed storage effect on yield was related to storage period. Seed stored 5 days between treatment and planting produced better yields than seed stored 2 days. The longer storage period may have allowed the cut surfaces to heal more completely before planting. The observation of no significant effect due to storage ventilation treatment suggests that the plastic bags did not severely restrict ventilation, the seed carried low levels of disease inoculum, or the holding period was too short. Figure 3. Percent stand produced by seed given one of four seed treatments. Treat­ ments with the same letter are not significantly different. Figure 4. Total and U.S. #1 yield produced by seed given one of four seed treatments. Treatments with the same letter are not significantly different. Table 2. Percent stand and yield produced by seed given various storage treatments. Means are averaged over seed treat­ ments and other storage treatments. Means within the same column and storage treatment followed by the same letter are not significantly different. Treatment Stand (%) Total Yield (cwt/A) U.S. #1 Yield (cwt/A) Storage Period 0 days 2 days Storage Period 5 days Storage Period Storage Temperature 98.7 a 97.6 a 98.7 a 52°F ambient air temp. Storage Temperature 97.0 a 98.9 a Storage Ventilation good Storage Ventilation poor 98.1 a 97.8 a 284 ab 276 b 299 a 289 a 285 a 287 a 287 a 262 ab 254 b 276 a 268 a 262 a 263 a 267 a Field Experiment #2 This experiment evaluated the effect of several chlorine wash treatments on 3 varieties over a range of spring soil conditions. Atlantic, Russet Burbank, and Monona seed was cut, treated, and planted on May 4, May 16, and June 1. The 8 seed treatments were: 500 ppm C1 wash, inoculated with Fusarium spores. 2000 ppm C1 wash, inoculated with Fusarium spores. a) no treatment, inoculated with Fusarium spores. b) water wash, inoculated with Fusarium spores. c) d) e) captan-streptomycin dust, inoculated with Fusarium spores. f) water wash, not inoculated. g) h) 500 ppm C1 wash, not inoculated. 2000 ppm C1 wash not inoculated. In the inoculated treatments, whole seed was dipped 3 minutes in water containing Fusarium spores the day before it was cut, treated, and planted. At each planting date, a separate planting of only the Atlantic treatments was made. After 35-40 days, these plots were dug and rated for stand and seed-piece decay whereas the main 3 variety planting was harvested 125-126 days after planting. Results In almost all cases there was no significant difference between the inoculated and non-inoculated treatments. Therefore, means were averaged for the inoculated and non-inoculated treatments with the same chlorine level. Figure 5 shows the percent stand of the Atlantic planting for the 3 planting dates. In the May 4 planting, the captan-streptomycin treatment was significantly better than all treatments except the untreated check. The water treatment produced the poorest stand. There were no differences in stand due to seed treatment in the May 16 planting. In the June 1 planting, however, the high chlorine treatment reduced the stand significantly compared to the other treatments. In the 3 variety planting that was grown to maturity, the Russet Burbank and Monona varieties produced excellent stands, and seed treatment differences were not significant. To show the relationship between treatment and yield, Figure 6 shows the yield produced by the variety Atlantic in the main planting that was grown to maturity. Stand and yield are well correlated for the first two plantings, as treatment differences were similar to those for percent stand. In the third planting, however, they were not correlated, as the captan-streptomycin treatment produced a larger yield than any other treatment, and the 2000 ppm C1 treatment yield was not lower than the other treatments. The overall yields produced by the seed treatments, averaged over varieties and planting dates, are shown in Figure 7. The captan-streptomycin dust treatment produced the highest total and U.S. #1 yield, better than all treatments, except the high chlorine treatment. The yield from the water treated seed was significantly lower than the captan-streptomycin and high chlorine treated seed. In this experiment, it appears any benefit of the chlorine wash treatments is not due to their washing effect but to the chlorine in the wash, since the water treatments had the poorest yield. Specific gravity measurements for 3 inoculated treatments (no treatment, 500 ppm C1, and 2000 ppm C1) were made for each variety at each planting date (Figure 8). Under the conditions of this experiment, the average specific gravity increased slightly as the chlorine concentration increased. This increase is not likely due to any direct effect of the chlorine treatments, but possibly to the more vigorous stands produced from the chlorine-treated seed. Figure 5. Percent stand produced by Atlantic seed with 5 seed treatments and planted on 3 separate dates. Treatments with the same letter are not significantly different. Figure 6. Total and U.S. #1 yield produced by Atlantic seed with 5 seed treatments and planted on 3 separate dates. Treatments with the same letter are not significantly different. Figure 7. Total and U.S. #1 yield produced by seed given one of five seed treatments. Means are the average of the 3 varieties and the 3 planting dates. Treatments with the same letter are not significantly different. Figure 8. Specific gravity of tubers produced by seed given one of 3 seed treatments. Means are the average of 3 varieties and 3 planting dates. Treatments with the same letter are not significantly different. Conclusion Tentative conclusions that can be drawn from these studies are: - excessively high rates of chlorine may inhibit suberization and decrease stands. - rates of 500-2000 ppm C1 are fairly effective as seed tints, though not better than a captan-streptomycin dust tint. - chlorine under the conditions of this study did not adversely affect seed that is stored 2-5 days after tint. BIOLOGY AND CONTROL OF RHIZOCTONIA AND SCAB DISEASES OF POTATO Department of Botany and Plant Pathology R. Hammerschmidt INTRODUCTION Rhizoctonia and scab diseases of potato have increased in prevalence in Michigan in recent years. One possible reason for this is seed borne inoculum. In addition to surface and pitted scabbing of tubers by the scab pathogen, this pathogen can also cause cankers on stems, stolons, etc. Similarly, Rhizoctonia has been reported to cause a scab like disfiguration of tubers as well as cankers of stems, sprouts and stolons. The general objectives of the reported research were, therefore, to evaluate the possible involvement of tuber borne inoculum in these diseases and to further evaluate the causes of scab-like tuber disfiguration and cankering of stems, sprouts and stolons. RESULTS I. Characterization of organisms causing sprout, stem and stolon cankers Cankering of sprouts, stolons and stems is of potential importance due to stand reduction and/or delayed emergence, reduction of tuber set, and girdling of stems which may result in aerial tuber formation, respectively. Studies were carried out to determine the identity of some of the organisms causing these symptoms. Onaway potato, planted on 16 May 1983 at MEF, was used for the sampling. The tubers used for the planting were selected for the presence of both scab lesions and Rhizoctonia black scruf sclerotia. Sampling was performed on 1 and 17 June 1983 by digging up entire plants. Sprouts, stems and stolons exhibiting brown lesions were analyzed for the presence of pathogens by standard technique. Ten hills were sampled each time. The first sampling demonstrated a high level of sprout killings (Table 1). Isolations from the lesioned tissue yielded Rhizoctonia in over 90% of the samples. No Streptomyces or Colletotrichium were detected. Fusarium was found in several samples which also had Rhizoctonia. The cool, wet weather at this time may have contributed to the symptom expression, as no tuber sampled was free of sprout-tip killing or sprout cankers. The second sampling date concentrated on stem and stolon canker (Table 1). Numerous dark brown stem cankers were observed on samples from each hill. These lesions tended to be somewhat sunken and often 1 cm or more in size. Most of these cankers yielded Rhizoctonia. Many tan to light brown lesions several mm in size were also observed. These lesions yielded Streptomycetes upon isolation onto water agar. Many small, dark brown lesions also appeared on most of the plants. Some of these flecks appeared slightly above ground as well as underground. These flecks yielded Colletotrichum and Rhizoctonia. The above ground flecks yielded primarily Colletotrichum. A similar pattern was observed on stolons. Large dark brown cankers yielded Rhizoctonia and some Colletotrichum. Light brown lesions yielded Streptomycetes. Although no complete girdling of stems or stolons was observed, the results suggest that the potential for this does occur. II. Further characterization of organisms causing scab-type symptoms. Tubers exhibiting scab symptoms were collected at MEF, in Tuscola County at the scab disease resistance trial and via MSU/CES and MCIA from Montcalm, Kent and Antrim counties were tested for the presence of pathogens capable of causing surface disfiguration. Streptomycete were associated with common, raised and pitted scab type lesions. A severe russetting and roughening of tuber skin observed on several tubers as associated with Rhizoctonia but not Streptomycetes. This condition looked very much like coalesced scab lesions, but had a great deal of Rhizoctonia mycelium associated with the lesion. Several tubers with a flaky, slightly grey scab-like lesion were associated with Colletotrichum infections. These results indicate that more than one type of organism is capable of causing scab like disfiguration in Michigan, with Streptomyces and Rhizoctonia responsible for most of the symptoms. III. Effect of formaldehyde seed treatment on expression of Rhizoctonia and Scab. Field Trials: Onaway B size seed, selected for presence or absence of Rhizoctonia black scruf were used. The seed pieces with no visible scruf were considered "good" seed; the remaining seed was used for planting after a 5 minute dip in 2% formaldehyde, dust with NTN 19701 (an experimental Rhizoctonia fungicide pro­ vided by Mobay Chemical Co.) or left untreated. Plantings were performed on May 16 and June 1. Each treatment was replicated four times per planting time. Eight hills per treatment per time period were sampled on 16 July for stem cankering assessment (Table 2). Tubers harvested on September 20, were evaluated for yield (Table 3). The tubers resulting from treated seed or from clean seed had fewer or no scruf sclerotia and a smoother, whiter skin than tubers developed from scruf infested seed. Greenhouse Trails: Scabby or scruf covered B sized seed was dip treated for 5 minutes with 2% formaldehyde or with distilled water. After drying, the tubers were planted in steamed soil. For Rhizoctonia, the tubers were planted 2" above the bottom of a 6 inch pot and watered daily. Tubers were evaluated for cankers when sprouts were 2-3" tall. For scab, the tubers were planted in pots which had a 3 inch layer of steamed soil upon which a wide mesh screen was placed. The seed piece was placed on this screen and then covered with steamed soil. The plants were top watered with emergence. They were then bottom watered to allow for optimal scab development conditions in the tuberization zone. The results (Table 4) indicate that formaldehyde has a beneficial effect on pre­ venting the development of scab and rhizoctonia from infected seed. The pot design used for the scab trials is being currently tested as a way to test for scab in infested field soil and will be tested for use in examining treatments which may result in scab reduction (e.g. pH adjustment, water potential, varietal resistance). The results strongly suggest that treatment of seed pieces with formaldehyde can have a significant effect on the expression of Rhizoctonia with respect to seed borne inoculum. Although total yields were not appreciably effected, the distribution of sizes and quality was positively effected by seed treatment or use of disease free seed. Greenhouse studies also indicate that formaldehyde has a positive effect on reducing scab development from infected seed. The relative importance of tuber borne inoculum vs. soil borne for both diseases will be continued using the pot techniques described above. IV. Development of a Rhizoctonia screening test A standardized technique for screening the resistance of tuber sprouts to Rhizoctonia solani was developed. This technique should be useful in screening large numbers of varieties in a short period of time. Tubers of Onaway potato were treated with 2% formaldehyde for 5 minutes. After air drying, the tubers were kept in the dark to allow sprouting. When sprouts were 3 mm in length, the eye containing the sprout was removed with a melon bailer. The sprout was then placed on 2 inches of steamed soil in a deep plastic pan. A 7 mm disc of Rhizoctonia solani was placed 3 mm from each sprout, and then the sprouts were covered with 3 inches of steamed soil. The soil was watered and the entire pan placed in a growth chamber at 60°F. Two weeks later the sprouts were removed from the soil, washed and examined for canker formation. Results thus far indicate that very uniform infection can be obtained this way, and thus should be a good technique for resistance screening. V. Disease resistance screenings. Disease resistance screenings for scab and observations on Rhizoctonia- related tuber disfiguration were made at Cass City, MI. The results (table 5) indicate there are a number of varieties which may have a suitable level of resistance to scab. In addition, preliminary observations also indicate some varietal differences with regard to scurf. TABLE 1 ORGANISMS ASSOCIATED WITH CANKERING SAMPLESa RHIZOCTONIA STREPTOMYCETES COLLETOTRICHUM June 1, sprouts June 16, stems June 16 stolons 19/20 16/20 3/20 0/20 4/20 3/20 0/20 8/20 6/20 aSamples consisted of two sprouts, steins or stolons exhibiting cankers from each of ten hills. Onaway potato, planted on May 16, was used for these samplings. TABLE 2 EFFECT OF SEED TREATMENT ON RHIZOCTONIA STEM CANKERING TREATMENT CANKER COVERAGEb RHIZOCTONIA STEM RHIZOCTONIA STEM CANKER COVERAGE b May 16 planting June 1 planting G F N B 2.1c 1.1 0.2 14.1 1.8c 0.9 0.3 12.3 aG = good or clean seed F,N,B = Scurf infested seed treated with formaldehyde, NTN 19701 or water, respectively bEvaluated on July 16 and Aug 1 for the May 16 and June 1 plantings, respectively cValues are percent of underground stem covered by canker TABLE 3 EFFECT OF SEED TREATMENT ON TUBER YIELD AND QUALITY TREATMENT a MAY 16 PLANTING MAY 16 PLANTING Yield (cwt/A) MAY 16 PLANTING Yield (cwt/A) MAY G F N B MAY 16 PLANTINGYield (cwt/A)Total 376.7 360.3 371.7 366.6 JUNE 1 PLANTINGJUNE 1 PLANTING G F N B 349.2 342.4 386.7 350.5 B's 49.3 26.6 35.6 46.8 No. 1 262.4 276.3 276.3 204.0 JUNE 1 PLANTINGJUNE 1 PLANTING 216.5 28.2 240.1 35.1 34.0 248.6 183.4 31.8 16 PLANTINGYield (cwt/A)Over 10 oz MAY 16 PLANTINGYield (cwt/A)Culls 21.9 27.6 6.4 25.5 43.1 29.8 53.4 90.3 JUNE 1 PLANTINGJUNE 1 PLANTING 42.9 24.7 51.0 51.4 61.6 42.5 53.1 83.9 aG = Good seed F,N,B - Scurf infested seed treated with formaldehyde, NTN 17901 or left untreated, respectively. TABLE 4 EFFECT OF FORMALDEHYDE ON SEED BORNE RHIZOCTONIA AND SCAB TREATMENTa WATER Formaldehyde RHIZOCTONIAb 12.1 0.1 SCABc 38/46 3/52 aTubers dip treated with distilled water or 2% formaldehyde for 5 minutes. bRhizoctonia = Percent area of stems covered by cankers and one month after planting (15 plants/ treatment). cScab = Number of scabby tubers/total tubers at 3 months after planting (15 plants/treatment). TABLE 5 SCAB RATINGS VARIETY SCAB TYPEa SCAB RATINGb RHIZOCTONIA OBSERVATIONSc 700-79 700-83 701-22 702-80 702-91 704-10 704-17 714-10 716-15 718-6 B9540-29 B9540-55 B9540-62 B9553-6 B7154-10 B7805-1 B9540-53 A72685-2 Atlantic Bel chip Belrus Centennial Chi pbelle Crystal Denali Jemseg Katahdin Kennebec Monona Oceania Onaway Pungo Rideau Rosa R. Burbank Ontario Sebago Shepody Snowchi p Yukon — C DP C C DP,R DP,R DP C C R — c c c C,R DP C R C - R, DP DP DP C, R C C C C C C C C DP C C C C C, R R, DP 0.9 1.2 1.2 0.2 1.3 1.3 3.2 1.1 1.1 2.1 0.0 0.4 0.1 0.5 1.4 1.1 0.0 0.9 1.4 0.6 0.0 0.5 1.5 1.4 2.1 0.5 1.1 1.0 2.3 0.4 0.1 0.3 0.4 1.8 0.1 0.4 1.6 0.3 2.3 2.0 RS, some scurf some scurf some scurf scurf scurf some RS, scurf some scurf RS, some scurf mild RS, scurf RS, some scurf RS, some scurf little scurf little scurf some RS, scurf little RS, scurf RS, scurf RS, scurf RS, scurf some scurf RS, some scurf some scurf some scurf scurf some scurf RS, some scurf little scurf some scurf some RS, scurf RS, scurf, rough cracks RS, scurf RS, scurf RS, some scurf little scurf some RS, scurf little scurf RS in cracks, scurf RS in crack, RS some scurf scurf, some RS RS, some scurf a C=common; R=raised; DP=deep pitted; -=no scab. b0=no scab; 1=1-10% scab coverage; 2=11-20%; 3=21-40%; 4=Over 40%. Results based on 80 tubers per variety. cRS=russet scab; scurf=sclerotia of Rhizoctonia solani. WEED CONTROL IN POTATOES (RESEARCH REPORT) Investigators: W. Meggitt, R. Leep, R. Chase, G. Powell, and R. Kitchen Department of Crop and Soil Sciences Studies were conducted at the Montcalm Farm and in the Upper Peninsula on the control weeds in potatoes. The results of herbicide treatments at the Montcalm Farm for control of broadleaf weeds and barnyardgrass are shown in Table 1. In 1983, EPTAM as a preplant incorporated treatment did not provide effective control of annual grass. This was probably due to poor incorporation as the soil was wet at time of second pass. There was a light rain after application, but not enough to move the herbicide into the soil. It is felt there was loss of EPTAM due to volatilization. Yields from treatments with EPTAM, where poor control resulted, were reduced. Applications of Fusilade applied postemergence gave excellent control of barnyard­ grass, however, broadleaved weeds became serious and resulted in severe yield reductions. Treatments with Lexone or Sencor or R-40244 (Racer) preemergence, provided excellent control of broadleaved and grass weeds and thereby no yield reductions when used with EPTAM. Combinations of Lasso or Dual with Lexone or Sencor either preemergence or delayed preemergence as in previous years gave excellent weed control and no yield reduction. Lasso and Dual performed similarly with no significant differences in yield. PPG 844, a new experimental, offers promise for postemergence control of broadleaved weeds. Postemergence grass herbicides offer an excellent approval to complete control of barnyardgrass without potato injury. Crop oil concentrate was necessary to provide maximum control with grass herbicides. Potato yields again were somewhat variable, but there was no significant yield reduction when weeds were controlled with both soil and foliage applied herbicides. A second experiment involved the study of conventional hilling and early hilling in a system that considered several herbicides and time of application. The data in Table 2 shows the weed control and yields of 4 varieties in the conventional hilling treatments. Application of herbicides after early hilling resulted in mechanical damage to potatoes from the tractor and therefore yields were not considered meaningful. In general, the treatments listed in Table 2 are those available to the grower with the exception of Fusilade, which does not have a registration for potatoes at present time. There were no significant differences in yields among any herbicide treatments on any variety. All herbicides at all times of application gave nearly complete weed control with only the EPTAM + Lexone/Sencor being at 90%. Table 1. Weed Control Evaluations in Potatoes, Montcalm County, Michigan 1983. Date Planted: Variety: Row Spacing: Plot Size: No. of Replications: 3 Incorporation Equipment: Springtooth Drag x 2 5/6/83 Russett Burbank 34" 102" x 50' *COC - Crop Oil Concentrate **Treatments 1-3, 7, 8 sprayed post prior to hilling. Date Treated: PPI - 5/6/83 PRE - 5/6/83 Delayed PRE (DP) - 5/26/83 POST - 6/22/83 Date Rated: Early - 6/22/83 Late - 7/27/83 Loamy Sand Soil Texture: Organic Matter: 2.0% Soil pH: 6.2 Weeds Present: Redroot pigweed, Common lambsquarter and Barnyardgrass Trt. No. Treatments PPI Eptam + [Fusilade + COC* (POST)]** PPI Eptam/R33865 + [Fusilade + COC (POST)]** PPI Eptam/R33865 + [Fusilade + COC (POST)]** PPI Eptam + [R40244 (PRE)] PPI Eptam + [R40244 (PRE)] PPI Eptam + [R40244 (PRE)] PPI Eptam + [R40244 (POST)]** PPI Eptam + [R40244 (POST)]** PPI Eptam + [Lexone/Sencor (DP)] PRE R40244 R40244 PRE Lasso + Lexone/Sencor PRE Dual + Lexone/Sencor PRE 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. Rate (lb/A) 4 + [1/8 + 1 qt] 3 + [1/8 + 1 qt] 4 + [1/8 + 1 qt] 3 + [1/4] 3 + [1/2] 3 + [1] 3 + [1/2] 3 * [1] 3 + [1/2] 1/2 1 2 + 1/2 2 + 1/2 6-22-83Rrpw 3 Colq 6-22-83 6-22-8 Bygr 6-22-83 Injury 0.0 0.0 0.0 10.0 10.0 10.0 0.0 0.0 10.0 10.0 10.0 10.0 10.0 0.0 0.0 0.0 10.0 10.0 10.0 0.0 0.0 10.0 10.0 10.0 10.0 10.0 2.0 4.3 4.7 9.3 9.8 9.8 3.3 0.7 10.0 9.2 10.0 10.0 10.0 0.0 0.0 0.0 1.3 0.3 0.3 0.0 0.0 0.3 0.0 1.0 0.0 0.0 7-27-83Rrpw 1.7 2.3 4.3 10.0 10.0 10.0 7.0 10.0 9.7 10.0 10.0 10.0 10.0 7-27-83 Colq 7-27-83 Bygr Yield CWT/No. 1 1.7 2.3 4.3 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 6.7 8.7 8.3 1.3 2.0 9.3 8.3 9.3 10.0 10.0 95 146 189 237 285 277 137 139 295 296 271 293 297 Table 1: Weed Control Evaluations in Potatoes, Montcalm County, Michigan 1983 (Continued) Trt. No. Treatments PRE Prowl + Lexone/Sencor PRE Surflan + Lexone/Sencor Lasso + [Lexone/Sencor (DP)] PRE Dual + [Lexone/Sencor (DP)] PRE Dual + PPG 844 PRE Dual + PPG 844 PRE No Treatment PRE 14. 15. 16. 17. 18. 19. 20. Rate (Ib/A) 1 1/2 + 1/2 3/4 + 1/2 2 + [1/2] 2 + [1/2] 2 + 1/5 2 + 2/5 - Rrpw 6-22-83 6-22-83 Colq 6-22-83 Bygr 6-22-83 Injury Rrpw 7-27-83 7-27-83 Colq 7-27-83 Bygr Yield CWT/No. 1 10.0 10.0 10.0 10.0 10.0 10.0 0.0 10.0 10.0 10.0 10.0 10.0 10.0 0.0 10.0 9.7 10.0 10.0 10.0 10.0 0.0 0.0 0.7 0.0 1.0 0.0 0.3 0.0 10.0 10.0 10.0 10.0 8.7 9.7 0.0 9.7 10.0 10.0 10.0 10.0 10.0 0.0 10.0 10.0 10.0 10.0 9.7 9.7 0.0 (LSD) = 283 269 312 269 281 275 73 46 Table 2. Weed Control and Variety Study in Potatoes, Montcalm County, Michigan 1983. 5/11/83 Onaway, Monona, Burbank, Atlantic Date Planted: Variety: Row Spacing: Plot Size: No. of Replications: 3 Incorporation Equipment: Springtooth Drag x 2 34” 136” x 50' *COC = Crop Oil Concentrate Weeds Present: Redroot pigweed, Common lambsquarter and Barnyardgrass Date Treated: PPI - 5/11/83 PRE - 5/11/83 Delayed PRE (DP) - 5/26/83 POST - 6/22/83 Late - 7/27/83 Loamy Sand Date Rated: Soil Texture: Organic Matter: 2.0% Soil pH: 6.2 Trt. No. Treatments 1. 4. 5. 6. 2. 3. PRE PPI Eptam + [Lexone/Sencor (DP)] PRE Lasso + [Lexone/Sencor (OP)] Dual + [Lexone/Sencor (DP)] DP Lexone/Sencor + [Fusilade + COC* (POST)] PPI Eptam + [Lexone/Sencor (DP)] + [Dual + Lexone/Sencor (Layby)] PRE Lasso + [Lexone/Sencor (DP)] + [Lasso + Lexone/Sencor (Layby)] 7. PRE Dual + [Lexone/Sencor (DP)] + [Dual + Lexone/Sencor (Layby)] Rate (Ib/A) 4 + [1/2] 2 + [1/2] 2 + [1/2] 1/2 + [1/4 + 1 qt] 4 + [1/2] + [1 + 1/4] 2 + [1/2] + [1 + 1/4] 2 + [1/2] + [1 + 1/4] 7-27-8 3 Rrpw 7-27-83 Colq 7-27-83Bygr Yield, CWT/No. 1Onaway Yield, CWT/No. 1 Monona Yield, CWT/No. 1 Burbank Yield, CWT/No. 1 Atlantic 9.0 10.0 9.0 10.0 10.0 10.0 10.0 9.7 10.0 10.0 10.0 10.0 394 377 415 417 329 365 346 415 311 302 299 315 10.0 10.0 10.0 417 357 254 9.7 10.0 9.7 10.0 10.0 10.0 (LSD) = 370 399 52 405 393 46 258 280 48 448 505 460 461 462 452 505 57 BIOLOGY & CONTROL STRATEGIES FOR INSECT PESTS OF POTATOES E.J. Grafius, H.T. Bell, and M.E. Otto Department of Entomology Research in 1983 was aimed at: 1. Continued evaluation of insecticide resistance in Michigan Colorado potato beetles, 2. Demonstration of pest management techniques for control of resistant potato beetles, and 3. Preliminary evaluation of an imported egg parasitoid of the Colorado potato beetle. 4. European corn borer management research was also planned, but populations and damage in potatoes were very low. Summary of Results 1) Laboratory evaluation of insecticide toxicity indicated varying levels of tolerance to Temik. Preliminary feeding trials supported the conclusion that significant levels of resistance are present. The parathion resistance reported in 1982 appeared to be very unstable and did not persist in the laboratory or in the field in subsequent generations of beetles without heavy selection pressure. Sevin resistance was present in what appeared to be a genetically mixed form with individuals from the same population being either susceptible or highly resistant. 2) The pest management demonstration in Monroe County was conducted in a field that began with up to 4-5 beetles per plant after Temik treatment. Results showed that resistant beetles could be kept below economic levels using careful scouting, choice of insecticides, and precise timing of applications. Reduced frequency of insecticide application and proper choice of materials should help slow the rate of resistance build-up. 3) Experiments with the egg parasitoid, Endovum puttleri (a tiny wasp) showed it to be difficult to rear in the laboratory and to require precise timing for release. Host eggs must be less than 24 hours old for attack to be successful. 4) A corn borer management plan was circulated to a number of potential cooperators for evaluation and followed up by phone calls, visits and contacts with scouts. No significant infestations or damage were reported. Insecticide Resistance Laboratory trials were conducted as before, using precise topical applications of technical grade insecticides. Beetles used were all field-collected and were fed untreated potato foliage during the experiments. Treatment of Monroe County beetles with Sevin (carbaryl) caused 45% mortality at a moderate dose, but the remaining 55% of the population appeared to be completely immune to doses as high as could be applied (Fig. 1). Studies with parathion showed none of the extreme resistance reported in 1982 from a field that had been treated weekly with parathion. However, all locations in 1983 showed 10- 20X resistance compared to the beetles from Antrim County (Table 1). Topical studies with Temik (aldicarb) showed only moderate differences between the Antrim County (susceptible) beetles and the other locations (Table 2). The low slope of the relationships for the commerical fields in 1983, however, indicates that a few individuals may be showing high levels of tolerance. LD50 values for Temik (and probably also other materials) varied widely from date to date. Beetles collected in the spring were much less tolerant to Temik than individuals collected from the summer generation (Table 3). This type of variation has been shown on the East Coast and reflects the overall vigor of the individual and the stress of overwintering and perhaps the previous insecticide treatment history. These and results from the East Coast indicate that spring treatment will be much more effective in reducing populations than fall treatment. The overall resistance picture is one that appears to be fairly widespread and may be rapidly changing. Preliminary feeding trials were conducted with Colorado potato beetle adults on potato foliage treated in the field under normal commercial conditions. Temik was applied at 3 lb. ai/A at planting (4-6 weeks before the test). Pydrin was applied at 0.2 lb. ai/A (3 days before the test). Although beetles from other locations were not evaluated, it is known that the foliage from the Montcalm Experimental Farm was toxic to beetles at that location. Samples of the foliage were collected and frozen for residue analysis. There was no mortality of any of the beetles fed Temik-treated foliage, regardless of location where the foliage was collected (Table 4). Pydrin, 3 days after treatment, caused some mortality. Residue analysis results are not available at the time of this report. Colorado Beetle Pest Management Demonstration A plot was set up on the Horkey farm in Monroe County, where severe beetle problems had existed in 1982. The field was scouted every week and treatments applied with a boom sprayer as needed. One half of the field was treated generally according to M.S.U. recommendations (treat if adults and larvae = more than one per plant) and the other half was treated at the grower's option. A small corner of the field was left largely untreated during the season to evaluate the effectiveness of the control programs and act as a biological control plot. Temik was applied at planting, but gave very little control two weeks after plant emergence and beyond. In view of the cost and our desire to minimize selection for Temik resistance, this treatment should not have been applied. Adequate (and nearly identical) control was obtained in both halves of the field. Treatments were applied every 1-3 weeks, with generally no more than one insecticide applied at a time (Table 5). The only major difference in beetle populations between the two sides of the field occurred in late July when the M.S.U. plot showed primarily eggs and adults while the other side of the field had mostly larvae (Fig. 2). This was perhaps caused by early season sprays changing the age structure of the two populations. Plant vigor and foliage was generally less on the M.S.U. side of the field and yields were lower (estimated total yield 91 lbs/100 row ft vs. 158 lbs/100 row ft on the other side of the field). Biological Control Endovum puttleri were reared in the laboratory on eggs from a potato beetle culture. Adults or pupae were released on two occasions, once in a "biological control" plot in the Monroe County field and once at the Montcalm County research farm. No parasitized eggs were found at either location. In one case, the plot was accidently sprayed the day after release, killing the parasitoids and eliminating their hosts. In the other release, potato beetle egg densities were low and not as many parasitoids were available from the laboratory for release. Results of a number of researchers experimenting with E. puttleri were also generally discouraging. This research will not be pursued in Michigan in 1984. However, given the amount of time and effort being expended by researchers and the outstanding success of biological control against other pests (such as the cereal leaf beetle and alfalfa weevil in Michigan), biological control will undoubtably be a major potato beetle management tool in the future. European Corn Borer Management A management program, along with instructions for evaluating the effectiveness of the program and the impact of corn borers on potato yield was developed. This program was not intended as a general practice, but for experimental purposes. No data was obtained on effectiveness or impact of corn borers due to low population levels in potatoes. Acknowledgments: Thanks to Karl Horkey for his cooperation; Paul Marks, and Andrea Adams for their help. Figure 1. Susceptibility of Colorado potato beetles to carbaryl (Sevin). Figure 2. Population densities of Colorado potato beetle eggs, larvae and adults in Monroe Co. demonstration field (arrows denote insecticide treatments). Table 1 Susceptibility of Colorado Potato Beetles to Parathion (LD50 = dose causing 50% mortality) PARATHION empty table cell LD50 (µl/beetle) Slope Antrim Montcalm .0005 .009 1.9 3.4 Monroe field 1 Monroe field 1 .113 (1982) 1.3 .010 (1983) — field 2 .001 (1982) 2.1 Monroe Monroe field 2 .005 (1983) 1.8 Table 2 Susceptibility of Colorado Potato Beetles to Temik (LD50 = dose causing 50% mortality) ALDICARB empty table cellLD50 (µg/beetles) Slope 4.0 9.6 1.0 Antrim 0.7 Montcalm Monroe field 1 8.4 (1982) 4.0 11.8 (1983) 0.8 field 2 2.2 (1982) 2.6 Monroe 17.5 (1983) 0.8 Monroe field 1 Monroe field 2 Table 3 Susceptibility of Colorado Potato Beetles Collected on 3 Dates to Temik ALDICARB empty table cell (µg/beetle) LD50 Monroe field 2 Aug 1982 2 May 1983 Monroe field 2.2 0.5 Monroe field 2 Aug 1983 17.5 Table 4 Preliminary Colorado Potato Beetle Feeding Trials with Temik-treated Foliage June 15-20, 1983 Food Untreated Temik (Monroe Co. site 1) Temik (Montcalm Exp. Farm) Temik + Pydrin (0.2 lb. ai/A, 3 days post-spray) (Monroe Co. site 1) Temik + Pydrin (0.2 lb.ai/A, 3 days post spray) (Monroe Co. site 2) Untreated Temik (Monroe Co. site 1) 0 a 0 a % Mortality (5 days)* 0 a 0 a 5 a 15 ab 25 ab Temik (Montcalm Exp. Farm) Temik + Pydrin (0.2 lb ai/A,3 days post spray) (Monroe Co. site 1) Temik + Pydrin (0.2 lb. ai/A, 3 days post spray) (Monroe Co. site 2) 5 a 10 a 35 b empty table cell Field-Collected Beetles (Monroe Co.) Field-Collected Beetles (Monroe Co.) Field-Collected Beetles (Monroe Co.) Field-Collected Beetles (Monroe Co.) Field-Collected Beetles (Monroe Co.) Lab-Cultured Beetles Lab-Cultured (Monroe Co. Source) Beetles (Monroe Co. Source) Lab-Cultured Beetles (Monroe Co. Source) Lab-Cultured Beetles (Monroe Co. Source) Lab-Cultured Beetles (Monroe Co. Source) * Means followed by the same letter are not significantly different (SNK test, p>0.05). Table 5 Treatment Schedule for Monroe Co. Demonstration Field 1983 M.S.U. Pydrin 2.4EC, 1/2 pt. Grower none Guthion 50WP, 1 lb. Guthion 50WP, 1 lb. none Guthion 50WP, 1 lb. Pydrin 2.4EC, 1/2 pt. Pydrin 2.4EC, 1/2 pt. Pydrin 2.4EC, 1/2 pt. Pydrin 2.4EC, 1/2 pt. + Imidan 50WP, 1 lb. + Imidan 50WP, 1 lb. Parathion 8EC, 1/2 pt. Parathion 8EC, 1/2 pt. Pydrin 2.4EC, 1/2 pt. Pydrin 2.4EC, 1/2 pt. + Imidan 50WP, 1 lb. + Imidan 50WP, 1 lb. Date 6/16 6/23 7/2 7/9 7/13 7/26 8/29 1983 MICHIGAN POTATO NEMATOLOGY RESEARCH REPORT G.W. Bird Department of Entomology 1982 Nematode Survey.-A nematode survey of Michigan potato production was conducted in 1982 to determine the impact of nematicides on Michigan potato productivity. The procedure and sites were the same as those used in the 1975 survey. Both studies were sponsored by the Michigan Potato Industry Commission. The 1982 survey consisted of 96 potato fields in fifteen different potato growing regions. Often the same locations as surveyed in 1975 were sampled. Each sample site represented five acres. Approximately 1.2% of the 1982 Michigan potato acreage of the region. Eighty-nine percent of the sites in the 1982 survey were treated with an at-planting systemic nematicide-insecticide (Table 1); this was 4% more than were treated in 1975. Five different materials were used for pre-plant or at- planting nematode or insect control, with Temik 15G being the most common. Temik use increased 18% between 1975 and 1982; DiSyston use decreased 26%; Furadan use increased; and Vorlex and Thimet use remained constant. The nematicide-insecticide usage pattern varied greatly among the potato growing regions (Table 2). Table 1. At-planting nematicide-insecticide use in potato production in Michigan in 1975 and 1982. Chemical Acreage treated (%) 1975 Acreage treated (%) 1982 At-planting systemic nematicides-insecticides Temik DiSyston Vorlex Furadan Thimet Non-treated 85 46 35 2 1 1 15 89 64 9 3 12 3 11 1Based on a survey of 2% of the potato acreage in 1975 and 1.2% in 1982. Table 2. At-planting systemic nematicide-insecticide use pattern in Michigan in 1962.1 Areas Montcalm (14) Presque Isle (6) Van Buren (3) Manistee (3) Emmet (5) Delta (8) Monroe (6) Antrim (7) Allegan (13) Bay (4) Houghton (4) Dickinson (4) Iron (4) Luce (4) Jackson (5) Temik Vorlex Thimet Furadan DiSyston No Systemic 100 33 0 0 100 0 100 83 14 62 0 100 75 100 100 21 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 50 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 100 100 0 0 0 0 42 0 50 0 0 0 0 0 0 0 0 0 100 0 0 0 0 50 0 25 0 0 0 17 0 0 0 0 0 17 42 38 0 0 0 0 0 1Each field represented 5 acres. 2% of the Michigan potato acreage was included in the survey in 1975 and 1.2% in 1982. As with the 1975 survey, nematode control with both Temik and Vorlex was observed from an analysis of the survey data (Table 3). Relatively high nematode population densities were associated with the Furadan, DiSyston, and sites not receiving an at-planting systemic insecticide-nematicide treatment. Table 3. Root-lesion and root-knot nematodes in relation to nematicides- insectides used in Michigan potato production. Treatment (Sites surveyed) Total (86) Temik (57) Vorlex (3) Furadan (11) Thimet (3) DiSyston (8) No Treatment (7) Nematodes per 100 cm3 soil1 Nematodes per Root-lesion 100 cm3 soil1 Root-knot 92 35 0 294 38 237 95 42 36 0 32 4 75 89 1Mid-season sampling of five area portions of potato fields. Using an initial population density pathogencity threshold of 100 nematodes per 100 cm3 of soil, the root-lesion nematode was estimated to be a pathogen of potato in 18% of the sites sampled and a potato predisposition agent in 71% of the sites. Compared with 1975, this nematode's role as a pathogen slightly decreased, and increased in its role as a predisposition agent. A crop loss-benefit analysis associated with the root-lesion nematode in Michigan potato production was conducted. The potential estimated loss was 18%; however, the actual estimated loss was 4% ($1,870,000). Nematicide treatments in 1982 cost Michigan growers $1,256,000. Approximately 37% of this was unnecessary. Management of the root-lesion nematode resulted in an 11% benefit to Michigan potato producers (Table 4). Fifty-six percent of the sites were properly managed to control the root-lesion nematode. Twenty-nine percent of the sites were treated with the nematicide when it was not needed; however, the materials may have been necessary to control other pests. Fifteen percent of the sites would have benefited from additional nematode management. nematode associated with Michigan potato production, population information about this nematode was recorded throughout the survey. There appeared to be a slight increase in the average root-knot nematode population density associated with Michigan potato production since 1975. The Columbia root-knot nematode has not yet been found in Michigan. Table 4. Influence of the root-lesion nematode on Michigan potato production Although research data are not available for an analysis of the root-knot in 1982. empty table cell Estimated loss ($) Loss-Benefit Analysis Loss-Benefit Analysis 1982 Unnecessary treatment cost 464,000 Estimated potential loss 7,383,400 1982 Crop loss estimate Loss-Benefit Analysis 1982 Treatment cost Loss-Benefit Analysis 1982 Total cost Loss-Benefit Analysis Management System Analysis 1,870,000 1,256,000 3,126,000 empty table cell Sites properly managed Sites over-treated Management System Analysis Sites needing additional management Management System Analysis empty table cell empty table cell Estimated loss (%) 18 37 4 3 7 56 29 15 Evaluation of Nematicides for Control of Root-Lesion Nematode in Potato Production.-The experiment was conducted at the Michigan State University Montcalm Potato Research Farm in Entrican, Michigan. The soil was a MacBride sandyloam. The land was plowed immediately before planting on May 3. Six nematicide treatments were evaluated in a randomized complete block design. Each plot consisted of four rows (15.25 meters length and 0.86 meters apart with 20.5-30.5 centimeters spacing between plants. Mocap 10G, Temik 15G and Oxamyl 10G were applied at planting in the fertilizer furrow. Oxamyl and Mocap were incorporated broadcast applications immediately prior to planting. Mocap was also applied as a sidedress treatment 45 days after planting. Commerical insect, disease and irrigation schedules were used throughout the season. Soil samples for nematode analysis (centrifugation­ flotation, 1.14 specific gravity) were taken immediately before planting, at two dates during the growing season, and at harvest on September 13. Root samples were processed for nematodes (shaker technique) for the mid-season samples. The center two rows of each plot were harvested, graded and weighted. Application of Temik 15G provided excellent control of the root-lesion nematode (Table 5). Similar control was obtrained with incorporated broadcast applications of Mocap 10G and Oxamyl 10G. These three treatments resulted in significantly greater yield of Grade A and total potato tubers. Table 5. 1983 Michigan potato nematicide trial. Treatment Yield (cwt/A) Revenue increase1 Root-lesion nematode per 100 cm3 soil + g root (8/23/83) Non-treated Control Mocap 10G IF(3.0 lb ai/A) Mocap 10G 12" Ba (3.0 lb ai/A) Mocap 10G 6" + 5" LBa (3.0 lb ai/A) Mocap 10G Br(9.0 lb ai/A) Temik 15G IF(3.0 lb ai/A) Oxamyl 10G 12" Ba (3.0 lb ai/A) oxamyl 10G B (9.0 lb ai/A) 328a 350ab 327a 349ab 388bc 408c 350ab 391bc -.-- $ 61.50 -(73.00) 63.50 178.50 388.50 53.00 187.50 192c 59ab 152bc 97abc 27a 10a 132bc 23a 1Based on $5.00/cwt for Grad A, $8.00/cwt for oversize, $0.50 for Grade B; less cost of nematicide; less revenue from non-treated control. 1983 Potato Trial, Cornell Michigan, Delta County Summary.-The experimental site had a low to medium population density of root-lesion nematodes at planting (Table ? 1). Excellent control of the root-lesion nematode was obtained through at-planting application of Temik 15G (Table 6). The average tuber yield in the research site was 191.5 cwt/A for the variety Superior and 233 cwt/A for Russet Burbank (Table ? 2). Application of Temik 15G resulted in a 37 cwt/A total tuber yield increase for Superior and a 42 cwt/A total tuber yield increase for Russet Burbank (Table 2). The U.S. #1 tuber yield associated with the Temik treatment was 19 cwt/A greater than DiSyston for Superior and 42 cwt/A greater for Russet Burbank (Table 7). The root-lesion nematode, most likely interacting with the Verticillium-wilt fungus, was the problem in the research site in 1983. Control of this disease complex was obtained with application of Temik 15G at planting. Compared with DiSyston, application of Temik resulted in a net profit increase of $158.50/A for Superior and $230.50/A for Russet Burbank (Table 8). Table 6. Delta County nematode control. Root-lesion Nematode No. per 100 cm3 Root-lesion Nematode Root-lesion Nematode No. per 100 Root-lesion cm3 Nematode No. per Root-lesion Nematode Variety, Treatment No. per 100 cm3 soil5/5/83 1 soil 8/18/83 soil 9/28/83 gm root 7/12/83 No. per gm root 8/18/83 Superior, DiSyston Superior, Temik Russet Burbank, DiSyston Russet Burbank, Temik 13 13 13 13 120 16 98 9 16 21 78 23 5 0 32 0 20 0 36 0 1Average of four samples taken at random throughout the research site. Population density range = 4-22 root-lesion nematodes per 100 cm3 soil. Table 7. Delta County potato tuber yield Variety, Treatment Tuber Yield (cwt/A) Total Tuber Yield (cwt/A) A's Tuber Yield (cwt/A) B's Tuber Yield (cwt/A) K's Tuber Yield (cwt/A)Oversize Superior, DiSyston Superior, Temik Russet Burbank, DiSyston Russet Burbank, Temik 173 210 212 254 138 157 117 159 - - 54 51 36 43 33 37 0 10 2 7 Table 8 Delta County potato economic analysis Gross ($)1 Gross Net ($) Variety, Treatment Gross ($)1A's Oversize ($)1 B's-K's Gross ($)1 Total ($) Superior, DiSyston Superior, Temik Russet Burbank, DiSyston Russet Burbank, Temik 690.00 785.00 585.00 795.00 0.00 80.00 16.00 56.00 18.00 21.50 43.50 44.00 708.00 886.50 644.50 895.00 688.00 846.50 624.50 855.00 1Based on US #1 at $5.00/cwt, Oversize at $8.00/cwt, B's & K's at 0.50/cwt and $40.00 for Temik 15G (3.0 lb a.i./A, and $20.00 for DiSyston 15G (3.0 lb a.i./A). Integrated Potato Research: Root-lesion Nematode Control Root-lesion nematode (Pratylenchus penetrans) population densities at the beginning of the 1983 growing season were significantly greater following alfalfa than after rotation with corn. The influence of the previous crop on nematode population density was still evident at the end of the potato growing season. Nitrogen fertilizer had no direct impact on the population density of the root-lesion nematode. Temik 15G applied in the fertilizer furrow at-planting at 3.0 lb. a.i./A, Temik 15G plus Vorlex applied as a broadcast soil injection, and Temik 15G plus Vorlex applied as an in-row soil injection significantly reduced population densities of the root-lesion nematode(Table 9). This was determined from an analysis of both soil and root samples taken on August 1, 1983. Nematode population reduction was still evident at the end of the growing season. Because of very cool soil temperatures in May, population densities of the root-lesion nematode did not increase as much as usual. No significant differences in nematode population densities among the nematicide treatments were detected in samples taken during the first week of July. July is the time in most years when it is easiest to detect the impact of nematode control procedures on population densities. Control of the root-lesion nematode was correlated with increased tuber yield following crop rotation with both corn and alfalfa, and under both nitrogen fertilizer regimes. All three nematicide treatments resulted in a significant increase in both the gross and net income associated with potato production. The economic advantages of nematicide application following corn were less at the low nitrogen fertilizer level than at the high level. This was not evident with the alfalfa rotation. The nematode control and economic benefits associated with row application of Vorlex were equal to those of the broadcast application with Vorlex. The economic advantages of using both Vorlex and Temik 15G were favorable compared to the use of only Temik 15G, or not using a nematicide. Table 9. Root-lesion nematode control, MSU Integrated Potato Research Project Treatment Root-lesion nematode population density 2.0 g population density 100 cm3 soil 4/20/83 root 8/1/83 2.0 g root 9/28/83 population density 2.0 g roots 8/1/83 Root-lesion nematode population density soil & roots 8/1/83 Root-lesion nematode Root-lesion nematode population density Root-lesion nematode Corn - 75 N Check Corn - 75 N Temik - 75 N Temik & Vorlex (Broadcast) Corn - 75 N Temik & Vorlex (Row) Corn Corn - 225N Check - 225N Temi k Corn - 225N Temik & Vorlex (Broadcast) Corn - 225N Temik & Vorlex (Row) Corn Alfalfa - 75 N Check - 75 N Temik Alfalfa - 75 N Temik & Vorlex (Broadcast) Alfalfa - 75 N Temik & Vorlex (Row) Alfalfa Alfalfa - 225 N Check Alfalfa - 225 N Temik - 225 N Temik & Vorlex (Broadcast) Alfalfa - 225 N Temik 4 Vorlex (Row) Alfalfa 11.0a 9.9a 3.5a 10.5a 4.0a 2.5a 3.0a 8.0a 21.5a 23.0a 14.0a 14.5a 15.5a 47.0b 18.0a 20.0a 29.7ab 0.0a 0.0a 0.0a 13.7ab 0.7a 0.0a 0.7a 60.7c 0.3a 0.3a 0.0a 35.0b 0.7a 0.7a 0.3a 60.8c 14.7ab 9.7ab 3.0a 50.3bc 16.3ab 4.7a 1.3a 95.8d 10.7ab 8.3ab 15.0ab 127.0e 25.3ab 20.3ab 9.0ab 35.7b 0.5a 0.3a 0.2a 37.5b 0.2a 0.5a 0.3a 38.8b 0.7a 0.0a 0.2a 60.3b 0.2a 0.0a 0.0a 65.5b 0.5a 0.3a 0.2a 51.2ab 0.5a 0.5a 1.0a 99.5b 1.0a 0.3a 0.2a 95.3b 0.8a 0.7a 0.3a FUNGICIDE EVALUATIONS ON POTATOES Department of Botany and Plant Pathology M.L. Lacy A. Early Blight (Alternaria solani) Russet Burbank potatoes were planted at the MSU Muck Farm on May 17, 1983, in furrows on 32 inch centers, but every second row was left blank so that rows were 64 inches apart. This allowed free movement of tractor and sprayer through the plots without significant vine damage. Plots were sprayed weekly with a conventional John Bean boom sprayer at 100 psi, using two D2-25 cone nozzles at 45 degree angles on each row. Fungicides were applied in 50 gallons of water per acre. Sprays began on July 19 and terminated on September 7, 1983 (8 applications). Early blight developed naturally in the plots without inoculation. Most disease developed after September 1, when temperatures began to moderate somewhat from the consistently hot weather in July and August. Plots were visually rated for disease on September 21, 1983, and were harvested October 3-5. All Dithane M-45 treatments and combinations performed quite well in suppressing early blight, even when applied on a 14-day schedule (Table 1). It should be kept in mind, however, that conditions for disease development were not very favorable, and such results might not occur in another year. Alternating Ridomil MZ-58 and Dithane M-45 on alternate weeks worked very well, and two new formulations of M-45 (FZ flowable and DG dispersable granules) also performed well. Griffin’s experimental formulations of Maneb (designated GX) looked quite good. Surprisingly, Difolatan and Bravo did not perform very well under these conditions for early blight control. B. Late Blight (Phytophthora infestans) In spite of repeated inoculations, no late blight developed in these plots due to the unusually hot, dry weather in 1983. Table 1. Disease reaction and yields of potato (cv. Russet Burbank) treated with fungicides for disease control (1983). Material Rate/Acre Active Rate/Acre Formulation Frequency (Days) Disease x Rating Yield (lbs z per 50 feet of row) Ridomil MZ-58 and Dithane M-45 80W Dithane M-45 80W Dithane M-45 68DG Dithane M-45 80W plus Duter 47.5W Dithane M-45 80W Dithane M-45 80W plus RH 7731 50W Dithane M-45 80W plus RH 7731 50W GX 011H GX 011H Dithane FZ Dithane M-45 80W Dithane M-45 80W GX 011H GX 022 Ridomil MZ-58 Dithane M-45 80W plus RH 7731 50W Bravo 500 Difolatan 80DG Bravo 500 Bravo 500 plus RH 7731 50W plus DS-59891 24W RH-7731 50W RH-7731 50W Bravo 500 plus DS-59891 25W Control 1.16 lb 1.6 lb 1.36 lb 1.6 lb 0.3 lb 1.6 lb 1.2 lb 0.06 lb 1.2 lb 0.125 lb 1.6 lb 1.2 lb 1.6 lb 0.8 lb 0.8 lb 0.25 lb 0.8 lb 1.6 lb 1.16 lb 0.8 lb 0.125 lb 1.11 lb 1.6 0.78 lb 0.78 lb 0.6 lb 0.125 lb 0.256 lb 1.04 lb 0.8 lb --- 2 lb 2 lb 2 lb 2 lb 10 oz 2 lb 1.5 lb 0.12 lb 1.5 lb 0.12 lb 1.6 qt 1.2 qt 1.6 qt 1.0 lb 1.0 lb 0.5 lb 0.8 qt 1.6 qt 2.0 lb 1.0 lb 0.25 lb 2 1/8 pts 2.0 lb 1.5 pt 1.5 pt 9.6 oz 0.25 lb 0.5 lb 2 pt 12.8 oz --- 14 (alternate 14 weeks) 7 7 7 14 14 14 7 7 7 14 14 7 7 14 14 7 7 14 14 14 14 14 --- 1.3 a y 1.8 ab 1.8 ab 1.8 ab 1.8 ab 1.8 ab 1.8 ab 1.8 ab 1.8 ab 2.0 ab 2.0 ab 2.0 ab 2.0 ab 2.3 abc 2.5 abc 2.5 abc 2.8 abc 3.0 abc 3.5 bc 3.5 bc 3.5 bc 3.5 bc 3.8 bc 4.0 bc LSD (0.05) empty table cell empty table cellempty table cell1.3 134.4 abc 132.6 abc 152.5 ab 138.6 abc 145.0 ab 135.9 abc 130.5 abc 146.6 ab 149.5 ab 154.5 a 134.9 abc 137.8 abc 121.6 abc 138.4 abc 153.0 ab 132.4 abc 137.9 abc 116.9 abc 113.5 abc 129.1 abc 111.3 bc 105.1 c 112.0 abc 102.1 c 34.5 x Based on a rating scale of 1-5, where 1 = 0-5%, 2 = 6-15%, 3 = 16-35%, 4 = 36-75%, and 5 = >75% of foliage diseased. y Means followed by the same letter do not differ significantly (P = 0.05) according to Duncan’s Multiple Range Test. z Potatoes smaller than about l 1/4 inches in diameter x 2 1/4 inches long were not harvested. THE INFLUENCE OF SELECTED PRODUCTION MANAGEMENT PRACTICES ON POTATO YIELD, QUALITY, AND NUTRITION M.L. Vitosh, G.W. Bird, R. Hammerschmidt, R.W. Chase, and E. Grafius Department of Crop and Soil Sciences, Entomology, and Botany and Plant Pathology The objective of the 1983 study was to optimize the inputs necessary for maximum tuber yield and excellent quality. From 1977 to 1980 a series of experiments were conducted to examine various nutrient-nematicide inter­ actions. The 1981, 1982 and 1983 experiments are a culmination of the pre­ vious studies plus an additional component, crop rotation. In 1983 the Atlantic variety was evaluated in a corn and alfalfa rotation with respect to its response to two nitrogen rates (75, 225 lb N/A) and four nematicide treatments (check, Temik, Vorlex-broadcast and Vorlex-row). METHODS In the spring of 1982, 6 blocks of alfalfa and corn were established at the Montcalm Research Farm. The alfalfa was cut periodically and top growth was left for organic matter accumulation. The corn was harvested for grain and stalks left in the field. Standard fertilizer practices were followed for both corn and alfalfa. The plots were plowed the first week in May and Vorlex applied May 6th. Broadcast Vorlex was applied with multiple chisels spaced 8 inches apart. Row applied Vorlex was applied on 34 inch centers under the row where potatoes were later planted. The broadcast treatment was 10 gallons of Vorlex per acre. The row treatment was 3 gallons of Vorlex per acre. All plots received the same tillage operations but no Vorlex was added to the check and Temik plots. All plots received 750 lbs of a 10-20-20 starter fertilizer at planting which occurred on May 17th. Temik 15G was banded with the starter fertilizer at a rate of 3.0 lbs active ingredient per acre to all plots except the 75 lb N- check and 225 lb N-check. The high N treatment was accomplished by side­ dressing 75 lb N/A on June 16 and again on June 27th at hilling. The nitrogen form was urea. Each plot consisted of four 34 inch rows, 50 feet long. Seed placement was 10 inches. The variety was Atlantic. The experimental design was a split-block design with 6 replications. Each replication was randomly split with the corn and alfalfa rotation. With­ in each rotation, two nitrogen treatments and four nematicide treatments were completely randomized. All plots received foliar applied insecticides and fungicides as needed to control insects and diseases based on weekly monitoring by the Montcalm County pest scouts. Soil samples were taken in April from each rotation block. Petiole samples were taken July 13th and analyzed in the laboratory for N, P, K, Ca, Mg, Zn, Mn, B, Cu, Fe, and Al. The two center rows of each plot were harvested on September 27, graded and weighed. Samples were taken for the determination of specific gravity and internal defects. Bulk samples were also taken from certain treat­ ments and are being evaluated in several storage experiments. An economic analysis of the data was performed using December prices. RESULTS Table 1 is a summary of the yield, economic analysis and specific gravity data. Because of this years experimental design, this is the first time we have been able to analyze rotations statistically. The 1983 data supports our previous data and contention that alfalfa grown just one year prior to potatoes produces the highest yields and economic returns when compared with corn. Specific gravity and small tuber yields (those under 2 inches in diameter) were not affected by the rotation. The data shown in Table 1 is the overall means for the main treatments in this study. Nitrogen response was similar to the alfalfa response in that the high N rate (225 lb N/A) produced the highest yields and economic returns. Small tuber yield and specific gravity were unaffected by N rate. Temik increased the yield of U.S. No. 1 potatoes by producing larger tubers and increased the yield of the 2-3 1/4 inch category. The addition of Vorlex (either row or broadcast) to Temik also resulted in significantly higher yields. This increase in yield came in the 2-3 1/4 inch tuber size category. Specific gravity, large tuber yield, and small tuber yield was unaffected by the four nematicide treatments. The greatest economic return from these treatments came from the Temik and the Temik plus Vorlex row-applied treatments. The addi- tional cost of the broadcast application of Vorlex resulted in lower economic returns than row applied Vorlex but comparable returns to the Temik alone treat­ ment. Table 2 summarizes the three-way interaction effect on yield, specific gra­ vity and economic returns. The U.S. No. 1 yield was significantly increased by the high N rate (225 lb N/A) in the corn-check but not the alfalfa-check. This implies that under a low management system, 75 lb N following alfalfa would be sufficient for maximum yields. The use of Temik and Temik + Vorlex at both N rates and rotations, however, resulted in higher yields of U.S. No. 1 potatoes. The response to these materials was greatest in the corn rotation at the high N rate and at the low N rate in the alfalfa rotation. Temik and high N combine together in the corn rotation to give an increase in large tuber yields, while Temik alone was responsible for most of the increase in large tuber yields in the alfalfa rotation. Vorlex when row applied tended to increase total yield by producing a increase in the 2-3 1/4 inch tuber category. Specific gravity was unaffected by any of the treatments. Net income and net income over the check (75 lb N corn-check) was greatest for alfalfa, low N and Temik + Vorlex row applied. Visual analysis for internal defects were inconclusive. A total of 25 tubers from each treatment were cut and visually examined. Slightly more hollow heart was observed in tubers from Vorlex treated plots, particularly in the corn rotation. A low incidence of vascular discoloration and internal necrosis did not appear to be related to any of the treatments. Ten tubers from each treat­ ment were chipped shortly after harvest. All treatments produced excellent chip quality with a rating of 1.0. In summary these studies have shown that intensive management of potatoes will optimize yield and profit. The nitrogen requirement for potatoes is more than double the requirement when following a corn crop compared to an alfalfa crop which is allowed to build organic matter and fix nitrogen in the soil. The use of Temik for the Atlantic variety, as well as Superior and other varie­ ties tested in previous years, contributes greatly to yield increase and pro­ fits regardless of whether the previous crop is corn or alfalfa. Although alfalfa contributes to higher yielding potatoes, a two year economic analysis of the data may not show significantly larger economic returns. The economic returns over a two year period would depend on whether the alfalfa is allowed to be removed and sold. In this experiment alfalfa was clipped and not removed. The price of corn and alfalfa and their yields would also enter into the calculation of the two year economic return. The previous years corn and alfalfa yields were not measured in this study. One would also have to speculate whether yields of potatoes following clipped alfalfa would be better than where the hay is removed. Nutrient Composition of Potato Petioles The nutrient composition of potato petioles sampled on July 13th is shown in Table 3. Nitrate nitrogen levels were significantly increased by alfalfa and the high N rate but not by the nematicide treatments. The rotation by N rate interaction shows that adding more than 75 lbs of N increased the nitrate nitrogen (N03-N) content when the previous crop was corn but not when the crop was alfalfa. This is in agreement with the yield data. Plants growing at this time of year had plenty of N when the previous crop was alfalfa and only 75 lbs of starter N fertilizer was applied. The effects of rotation were observed on Ca, Mn and Fe content of potato petioles. Significantly higher levels of Ca and Fe but lower levels of Mn were found in petioles from the alfalfa rotation. Soil test analysis showed higher Ca levels (1191 vs 960) in the alfalfa blocks than the corn blocks. Although pH was not significantly different between alfalfa and corn blocks, soil pH also tended to be higher in the alfalfa blocks (6.2 vs 6.1). This data would help to explain the higher Ca levels in plant tissue and lower Mn levels. Iron (Fe) will often show the opposite trend that Mn does. All plant nutrients ex­ cept N were found to be in the sufficiency range for optimum growth. Temik significantly increased the P content and decreased the Mg content of potato petioles; however, the change is small and the values are well above the critical levels. Vorlex significantly reduced the Mn level. This obser­ vation has been noted nearly every year. It is possible that the soil fumigant is affecting the soil microorganisms responsible for the oxidation and reduction of soil manganese (Mn) . It would appear that Vorlex results in less reduced Mn in the soil causing less Mn to be taken up. Manganese in soil is most readily available in its reduced form. Little or no significance can be concluded from these differences in Mn content because even the lowest levels are above the critical or deficient level. Several crop by N rate interactions were observed in addition to the one for NO3-N which was discussed earlier. These were for K, Mg, Cu and B. Little or no confidence can be placed in these statistically significant reactions be­ cause all levels are above the critical levels. Root-lesion Nematode Control Root-lesion nematode (Pratylenchus penetrans) population densities at the beginning of the 1983 growing season were significantly greater following alfalfa than after rotation with corn (Tables 4 and 5). The influence of the previous crop on nematode population density was still evident at the end of the potato growing season. Nitrogen fertilizer had no direct impact on the population density of the root-lesion nematode. Temik 15G applied in the fertilizer furrow at planting at 3.0 lb a.i./A, Temik 15G plus Vorlex applied as a broadcast soil injection, and Temik 15G plus Vorlex applied as an in-row soil injection significantly reduced popula­ tion densities of the root-lesion nematode. This was determined from an analy­ sis of both soil and root samples taken on August 1, 1983. Nematode population reduction was still evident at the end of the growing season. Because of very cool soil temperatures in May, population densities of the root-lesion nematode did not increase as much as usual. No significant dif­ ferences in nematode population densities among the nematicide treatments were detected in samples taken during the first week of July. July is the time in most years when it is easiest to detect the impact of nematode control proce­ dures on population densities. Control of the root-lesion nematode was correlated with increased tuber yield following crop rotation with both corn and alfalfa, and under both nitro­ gen fertilizer regimes. All three nematicide treatments resulted in a signifi­ cant increase in both the gross and net income associated with potato produc­ tion. The economic advantages of nematicide application following corn were less at the low nitrogen fertilizer level than at the high level. This was not evident with the alfalfa rotation. The nematode control and economic bene­ fits associated with row application of Vorlex were equal to those of the broad­ cast application with Vorlex. The economic advantages of using both Vorlex and Temik 15G were favorable compared to the use of only Temik 15G, or not using a nematicide. Foliar Disease Ratings Observations were made on the severity of early blight (Alternaria solani) at four times during the growing season. The severity of early blight in the integrated plot was not as great as last year, and the observed differences were not as great among or between treatments (Tables 6 and 7). In general, the potatoes following alfalfa rotation exhibited less disease symptoms than the corn rotation. High N levels were also associated with less severe disease. Unlike last year, there were no apparent differences among the insecticide treatments with regard to early blight expression. Symptoms of Verticillium wilt were observed in the plot. However, like last year, no significant dif­ ferences were noted among or between treatments. Table 1. Main effects of selected production management practices on potato yield, size, quality and income. Tuber YieldUS No. 1cwt/A Tuber Yield 2-3 1/4 cwt/A Tuber Yield Under 2" cwt/A Tuber Yield Over 3 1/4 cwt/A Tuber YieldTotalcwt/A Specific Gravity g/cc Incom e Net Income1 Dollars/A Income Net Income Over Check2 Dollars/A empty table cell Previous Crop Corn Alfalfa Previous Crop Nitrogen Rate 75 lbs/A 225 lbs/A Nitrogen Rate Nematicide 368 a 404 b 342 a 368 b 371 a 402 b 346 a 364 b 28 30 30 29 29 30 29 30 26 a 37 b 396 a 435 b 1.086 1.085 2420 a 2680 b 420 a 680 b 25 a 38 b 401 a 431 b 1.086 1.085 2450 a 2650 b 450 a 650 b 19 a 36 b 33 b 37 b 376 a 417 b 434 c 436 c 1.085 1.086 1.086 1.085 2350 a 2610 bc 2570 b 2690 c 350 a 610 bc 570 b 690 c Check Nematicide Temik Temik + Vorlex (Broadcast Nematicide Temik + Vorlex (Row) Nematicide 347 a 387 b 406 c 406 c 328 a 351 b 372 c 369 c 1Net income after treatment expenses: N @ 20¢/lb, Temik @ $40/A, Vorlex-row @ $45/A and Broadcast @ $150/A, tubers over 3 1/4” @ $8.65, tubers 2-3 1/4” @ $6.65 and tubers under 2" @ $1.00 2Check = corn at 75 lbs N/A with no nematicide applied. 3Any two means not followed by the same letter are significantly different by LSD method (P = 0.05). Table 2. Interaction effects of selected production management practices on potato yield, size, quality and income. empty table cell Tuber Yield US No. 1cwt Tuber Yield 2-3 1/4" cwt Tuber Yield Under 2" cwt Tuber Yield Over 3 1/4" cwt Tuber YieldTotalcwt Specific Gravity g/cc Income Net Income1 dollar/A Income Net Income Over Check2 dollars/A Corn - 75 N Check - 75 N Temik. Corn - 75 N Temik + Vorlex (Broadcast) Corn - 75 N Temik + Vorlex (Row) Corn Corn - 225 N Check - 225 N Temik Corn - 225 N Temik + Vorlex (Broadcast) Corn - 225 N Temik + Vorlex (Row) Corn Alfalfa - 75 N Check - 75 N Temik Alfalfa - 75 N Temik + Vorlex (Broadcast) Alfalfa - 75 N Temik + Vorlex (Row) Alfalfa Alfalfa - 225 N Check - 225 N Temik Alfalfa - 225 N Temik + Vorlex (Broadcast) Alfalfa - 225 N Temik + Vorlex (Row) Alfalfa LSD (.05) 297 314 375 360 354 412 428 407 377 420 393 430 361 403 425 425 (30) 291 300 357 347 329 366 384 364 353 372 362 384 339 365 385 381 (26) 28 28 28 27 30 28 27 29 32 30 30 35 25 34 29 29 6 14 18 13 25 46 44 43 24 48 31 46 22 38 40 44 (NS) (11) 325 342 403 387 384 440 456 436 409 450 423 465 386 437 454 454 (30) 1.086 1.086 1.087 1.086 1.085 1.085 1.085 1.084 1.084 1.086 1.087 1.085 1.085 1.086 1.084 1.085 empty table cell 2000 2090 2360 2350 2390 2770 2730 2690 2570 2860 2500 2890 2420 2710 2700 2810 0 90 360 350 390 770 730 690 570 860 500 890 420 710 700 810 (210) (210) Net income after treatment expenses: N @ 20¢/lb, Temik @ $40/A, Vorlex - row @ $45/A and broadcast @ $150/A, tubers over 3 1/4" @ $8.65, tubers 2 - 3 1/4" @ $6.65 and tubers under 2" @ $1.00. Check = Corn at 75 lbs N/A and no nematicide. Table 3. Main and interaction effects of selected production management practices on chemical analysis of potato petioles sampled on July 13th. NO3 -N ppm P% K % Ca % Mg % Mnppm Znppm Cu ppm Fe ppm Bppm Alppm 10770 16190 (2400) 0.49 0.51 (NS) 11.71 10.97 (NS) 0.97 1.11 (0.07) 0.47 0.52 (40) 223 172 (40) 40 41 (NS) 8.0 9.4 (NS) 58 66 (8) 34 34 (NS) 55 95 (NS) empty table cell Previous Crop Corn Alfalfa Previous Crop LSD (.04) Previous Crop N Rate 75 N Rate 225 LSD (.05) N Rate Nematicide 12730 14240 (870) 0.50 0.50 (NS) 11.49 11.18 ( .17) 1.04 1.05 (NS) 0.49 0.50 (NS) Check Nematicide Temik Temik + Vorlex (Broadcast) Nematicide Temik + Vorlex (Row) Nematicide LSD (.05) Nematicide 13080 13810 13450 13600 (NS) 0.47 0.50 0.54 0.50 (0.03) Previous Crop By N Rate Interaction Corn - 75 Corn - 225 Previous Crop By N Rate Interaction Alfalfa - 75 Previous Crop By N Rate Interaction Alfalfa - 225 Previous Crop By N Rate Interaction LSD (.05) Previous Crop By N Rate Interaction 9130 12420 16320 16060 (2060) 0.50 0.48 0.50 0.51 (NS) 11.24 11.48 11.41 11.23 (NS) 11.95 11.46 11.03 10.90 (.63) 1.06 1.02 1.04 1.05 (NS) 0.96 0.98 1.12 1.11 (NS) 0.50 0.48 0.48 0.51 (0.02) 0.46 0.48 0.52 0.51 (0.05) 187 208 (NS) 236 213 180 161 (36) 219 226 155 189 (NS) 39 42 (3) 9.4 8.0 (NS) 61 63 (2) 34 34 (NS) 73 77 (NS) 40 40 43 40 (NS) 38 42 40 42 (NS) 8.6 8.3 8.2 9.7 (NS) 60 64 63 62 (NS) 33 34 36 33 (NS) 57 59 65 67 (NS) 57 59 65 67 (3) 35 33 33 36 (3) 74 89 60 77 (NS) 42 67 104 86 (NS) Table 4. Root-lesion nematode populations in potato roots and soil as affected by previous crop, nitrogen rate, nematicide treatments and time of sampling. Root-lesion Root-lesion nemotode population density100 cm3 Root-lesion nemotode population Treatment nemotode population density 100 density 2.0 g Root-lesion nemotode population density Root-lesion nemotode population density100 cm3 soil4/20/83 cm3 soil 8/1/83 soil 9/28/83 root 8/1/83 Soil & roots 8/1/83 Previous Crop Corn Alfalfa Previous Crop Nitrogen Rate 75 lbs/A 225 lbs/A Nitrogen Rate Nematicide Check Temik Nematicide Temik + Vorlex Nematicide (Broadcast) Temik & Vorlex Nematicide (Row) 6.5a 1 21.7b 13.4ab 14.8ab 13.0ab 20.5ab 9.6ab 13.3ab 5.6a 12.3a 11.5a 6.4a 34.9b 0.4a 0.3a 0.3a 20.1a 40.6b 28.ab 32.6ab 86.9b 16.8a 10.8a 7.1a 9.4a 12.4a 9.5a 12.3a 43.0b 0.4a 0.2a 0.2a 15.0a 24.8a 21.0a 18.7a 77.9b 0.8a 0.5a 0.4a 1Any two means not followed by the same letter are significantly different according to the LSD test (P=0.05) Table 5. Root-lesion nematode populations in potato roots and soil as affected by selected production management practices (interaction effects). Treatment Root-lesion nematode population population density 100 cm3 soil 4/20/83 density 2.0 g root 8/1/83 density 2.0 g root 9/28/83 population density 2.0 g Roots 8/1/83 Root-lesion nematode population density soil & roots 8/1/83 Root-lesion nematode Root-lesion nematode population Root-lesion nematode Corn - 75 N Check - 75 N Temik Corn - 75 N Temik & Vorlex (Broadcast) Corn - 75 N Temik & Vorlex (Row) Corn Corn - 225N Check - 225N Temik Corn - 225N Temik & Vorlex (Broadcast) Corn - 225N Temik & Vorlex (Row) Corn Alfalfa - 75 N Check Alfalfa - 75 N Temik - 75 N Temik & Vorlex (Broadcast) Alfalfa - 75 N Temik & Vorlex (Row) Alfalfa Alfalfa - 225 N Check Alfalfa - 225 N Temik - 225 N Temik A Vorlex (Broadcast) Alfalfa - 225 N Temik & Vorlex (Row) Alfalfa 11.0a 9.9a 3.5a 10.5a 4.0a 2.5a 3.0a 8.0a 21.5a 23.0a 14.0a 14.5a 15.5a 47.0b 18.0a 20.0a 29.7ab 0.0a 0.0a 0.0a 13.7ab 0.7a 0.0a 0.7a 60.7c 0.3a 0.3a 0.0a 35.0b 0.7a 0.7a 0.3a 60.8c 14.7ab 9.7ab 3.0a 50.3bc 16.3ab 4.7a 1.3a 95.8d 10.7ab 8.3ab 15.0ab 127.0e 25.3ab 20.3ab 9.0ab 35.7b 0.5a 0.3a 0.2a 37.5b 0.2a 0.5a 0.3a 38.8b 0.7a 0.0a 0.2a 60.3b 0.2a 0.0a 0.0a 65.5b 0.5a 0.3a 0.2a 51.2ab 0.5a 0.5a 1.0a 99.5b 1.0a 0.3a 0.2a 95.3b 0.8a 0.7a 0.3a Table 6. Early blight ratings1 of Atlantic following alfalfa. Treatment Date 7/27 Date 8/3 Date 8/17 Date 8/31 75 lb N Check 75 lb N Temik lb N Temix+Vorlex (Broadcast) 75 lb N Temix+Vorlex (Row) 75 225 lb N Check 225 lb N Temik lb N Temix+Vorlex (Broadcast) 225 lb N Temix+Vorlex (Row) 225 0.5 0.4 0.4 0.5 0.1 0.0 0.0 0.0 0.7 0.4 0.4 0.6 0.2 0.1 0.1 0.0 1.2 1.1 1.0 0.9 0.4 0.4 0.5 0.3 2.1 2.0 1.8 1.9 0.5 0.3 0.6 0.4 1 0 = no symptoms; 1 = 1-10% coverage; 2 = 11-20%; 3 = 21-40%; 4 = over 41% coverage. Table 7. Early blight ratings1 of Atlantic following corn. Treatment Date 7/27 Date 8/3 Date 8/17 Date 8/31 lb N Check 75 lb N Temik 75 lb N Temik+Vorlex (Broadcast) 75 lb N Temik+Vorlex (Row) 75 225 lb N Check 225 lb N Temik lb N Temik+Vorlex (Broadcast) 225 lb N Temik+Vorlex (Row) 225 0.7 0.8 0.6 0.6 0.1 0.0 0.0 0.0 1.0 0.8 0.8 0.7 0.4 0.3 0.3 0.4 1.6 1.3 1.0 0.9 0.7 0.6 0.3 0.5 2.8 2.7 1.9 2.1 1.3 1.4 0.9 1.0 1 0 = no symptoms; 1 - 1-10% coverage; 2 = 11-20%; 3 = 21-40%; 4 = over 41% coverage. INFLUENCE OF FIELD PRODUCTION TREATMENTS ON THE QUALITY OF POTATOES OUT OF EXTENDED STORAGE (MSU 1982 INTEGRATED PROJECT - STORAGE PHASE} B.F. Cargill, R.L. Ledebuhr, K.C. Price, H.S. Potter, R.W. Chase, and M.L. Vitosh Department of Agricultural Engineering, Botany and Plant Pathology and Crop and Soil Sciences INTRODUCTION PROCEDURE This report contains data on the effect of various field production treatments on the quality of MSU grown Atlantic, Denali, and Russet Burbank potatoes out of extended storage. Potato Samples For the 1982 MSU integrated project three varieties of potatoes (Atlantic, Denali, and Russet Burbank) 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 23, 1982. Treatments All production treatments in this phase of the integrated potato project are field applied. All treatments had two crop rotation treatments. One set of treatments was performed in a corn rotation and one set of treatments was performed in an alfalfa rotation. For the Atlantics, 225 lbs/acre of nitrogen was applied to all three Atlantic treatments. The Atlantic treatment number 7 was a check. Atlantic treatment number 8 had a field application of Temik and Atlantic treatment number 9 had a field application of Vorlex. See Table 1. For the Denali, 225 lbs/acre of nitrogen was applied to one Denali treatment. The Denali treatment also had a field application of Temik and Vorlex. See Table 1. For the Russet Burbanks there were six treatments. Three were treated with 75 lbs/acre of nitrogen and three plots were treated with 225 lbs/acre of nitrogen. See Table 2. Table 1. Field Production Treatments for the MSU 1982 Integrated Project Atlantic Treatment Number Chemical Treatments (7, 8, 9) and Denali (10) Crop Rotation Alfalfa Alfalfa Alfalfa Corn Corn Corn Alfalfa Corn Table 2. Field Production Treatments for the MSU 1982 Integrated Project Russet Treatment Number Nitrogen lbs/acre Burbank Potatoes. Chemical Treatments Crop Rotation 7A 8A 9A 7C 8C 9C 10A 10C 1A 2A 3A 1C 2C 3C 4A 5A 6A 4C 5C 6C Check Temik Check Temik Temik & Vorlex Temik & Vorlex Temik & Vorlex Temik & Vorlex Check Temik Check Temik Check Temik Check Temik Temik & Vorlex Temik & Vorlex Temik & Vorlex Temik & Vorlex 75 75 75 75 75 75 225 225 225 225 225 225 Alfalfa Alfalfa Alfalfa Corn Corn Corn Alfalfa Alfalfa Alfalfa Corn Corn Corn Storage Environment After harvest all samples were bagged, tagged, and placed into one cubicle 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/week until the desired storage environment of 40°F and 95% r.h. was reached. Evaluation Weight Loss: All bagged potato samples were weighed after treatment; after two weeks suberization; and at the market quality evaluation date of June 1, 1983 (251 days in storage). Weight loss during storage is represented by a percent using the following equation: Where Wi = Initial weight We = evaluation weight Market Quality A market quality evaluation was made after the potatoes had been in storage for 251 days. The market quality evaluation involved removing the respective bagged samples from storage, emptying the bag, and examining each individual tuber. Each examined tuber was classified as follows: A. Marketable B. Non-marketable 0 to 5.0% soft rot 5. 0 to 5.0% dry rot 1. 6. 5.1 to 10.0% soft rot 2. 5.1 to 10.0% dry rot 7. 10.1 to 25.0% soft rot 3. 10.1 to 25.0% dry rot 8. over 25.0% soft rot 4. over 25.0% dry rot 9. Other reasons (but not due to storage, such as insect damage, excess scab, etc.) After the potatoes were classified, the non-marketable potatoes were counted and weighed. Marketable quality is represented by a percent and is determined by two methods: 1. By number of tubers: Where Mn = number of marketable potatoes in each sample Tn = total number of potatoes in each sample 2. By weight of tubers: Where Mw = weight of marketable potatoes in each sample Tw = total weight of potatoes in each sample RESULTS AND DISCUSSION Weight Loss Tables 3-5 show the weight loss data for the Atlantic, Denali, and Russet Burbank potatoes, respectively for the 1982 integrated potato project. Data from all three varieties show that there is less than a 2% difference between the various field treatments. This means that the various production treatments used in the integrated project have very little if any bearing on potato weight loss during storage. The weight loss factor (WLF) is the percent per day of weight loss in storage. 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. Table 3. Weight Loss Data from the 1982 Integrated Project Atlantic Potatoes Stored at 40°F and 95% r.h. Duration Days 83 Storage Duration Days 237 Wt. Loss % Storage Duration Days 237 WLF Storage WLF .051 .044 .048 .047 .046 .046 .046 .045 .045 Treatment Number Storage Duration Days83Wt. Loss % 7A 7C Avg. 8A 8C Avg. 9A 9C .037 .036 .036 .039 .039 .039 .033 .037 _______ Avg.__________ _________.035 Table 4. Weight Loss Data for the 1982 Integrated Project Denali Potatoes Stored at 4.3 3.6 3.9 3.9 3.8 3.9 3.8 3.7 3.8 8.7 8.5 8.6 9.3 9.3 9.3 7.8 8.9 8.3 40°F and 95% r.h. Treatment Number Storage Duration Days 83 Wt. Loss % Storage Duration Days 23 7 WLF .031 .028 .030 Table 5. Weight Loss Data for the 1982 Integrated Project Russet Burbank Potatoes Storage Duration Days 8 3 WLF .055 .047 .051 Storage Duration Days 237 Wt. Loss % 10A 10C Avg. 4.5 3.9 4.2 7.2 6.6 6.9 Stored at 40°F and 95% r.h. Storage Treatment Number Duration Days83Wt. Loss % Storage Duration 1A 1C Avg. 2A 2C Avg. 3A 3C Avg. 4A 4C Avg. 5A 5B Avg. 6A 6C Avg. Check Avg. Temik Avg. Temik & Vorlex Avg. Storage Duration Days 83 WLF .040 0.47 0.43 .039 .050 .044 .042 .054 .048 .030 .035 .033 .051 .059 .055 .040 .064 .047 .038 .047 .047 Days 237 Wt. Loss % 5.7 4.9 5.3 5.4 6.0 5.7 4.7 6.2 5.4 4.0 4.7 4.3 5.8 7.3 6.5 5.7 6.6 6.1 4.8 6.1 5.7 Storage Duration Days 237 WLF .024 .021 .022 .018 .025 .021 .020 .026 .023 0.13 .020 .016 .025 .031 .028 .024 .028 .026 0.19 .026 .021 3.3 3.9 3.6 3.2 4.1 3.6 3.5 4.5 4.0 2.5 3.7 3.1 4.2 4.9 4.5 3.3 4.7 4.0 3.4 4.0 4.0 Market Quality potatoes of the integrated project are shown in Tables 6-8, respectively. The market quality data (by weight) of the Atlantic, Denali, and Russet Burbank Table 6. Market Quality (by weight) of the 1982 Integrated Project Atlantic Potatoes Stored at 40°F and 95% r.h. Market Quality Treatment Number 10A 10C Avg. 7A 8A 9A 7C 8C 9C 1A 2A 3A 4A 5A 6A 1C 2C 3C 4C 5C 6C 7-Average 8-Average 9-Average Unaccountable potential research error - other #9 treatments did not show this difference in market quality. Table 7. Market Quality (by weight) of 1982 Inte­ grated Project Denali Potatoes Stored at 40°F and 95% r.h. Market Quality Treatment Number Table 8. Market Quality (by weight) of 1982 Inte­ grated Project Russet Burbank Potatoes Stored at 40°F and 95% r.h. Market Quality Treatment Number 93 88 85 88 86 76* 92.5 87.0 80.5 89 90 89.5 95 97 99 97 95 98 99 99 99 98 96 98 CONCLUSIONS 1. 2. The field production treatments in the 1982 integrated project using different rates of nitrogen, crop rotations, and treatments of Temik and Temik combined with Vorlex have very little affect on weight loss of potatoes out of extended storage. The field production treatments in the 1982 integrated project using different rates of nitrogen, crop rotations, and treatments of Temik and Temik combined with Vorlex have very little affect on market quality of potatoes out of extended storage. QUALITY OF STORED POTATOES DUE TO PRESTORAGE HANDLING, CHEMICAL AND MECHANICAL TREATMENTS, AND STORAGE ENVIRONMENTS (1982 INTEGRATED PROJECT) B.F. Cargill, R.L. Ledebuhr, K.C. Price, H.S. Potter, R.W. Chase, M.L. Vitosh, and J. Cash Department of Agricultural Engineering, Botany and Plant Pathology, Crop and Soil Sciences, and Food Science The objectives of the storage phase of the 1982 MSU integrated potato research INTRODUCTION project were: To compare the influence of prestorage mechanical and chemical treatments on the quality of Atlantic and Denali potatoes stored under various environments for extended storage periods. To investigate the effects of various application rates of prestorage chemicals (Mertect 340F and chlorine) and types of prestorage application equipment on marketable quality of stored potatoes. The economic value (market quality) of potatoes varies due to prestorage mechanical and chemical treatments and various storage environments. The overall objective is to try and determine the best combination of prestorage treatments and storage environments to maximize the economic value of potatoes out of storage. This report contains the 1982 results for the prestorage chemical and mechanical treatment and storage phase for Atlantic and Denali potatoes. PROCEDURE Potato Samples The 1982 integrated potatoes (Atlantic and Denali) were harvested from the Integrated plot at Michigan State University’s Montcalm Potato Research Farm at Entrican, Michigan using the one row plot harvester. The potatoes were divided into two lots. Lot I was controlled mechanically bruised by rerunning the potatoes two times over a PTO operated windrower with an engine speed of 700 rpm. Lot I was designated as bruised potatoes. Lot II was taken directly off the MSU plot harvester and was designated as nonbruised. Equipment The MSU research conveyor was used for the controlled application of fungicides and bacteriacides. The conveyor controlled the potato volume at 12 tons/hr (about 1/6 - 1/3 the rate of the commercial bin piler). The chemicals were applied with calibrated equipment. For the Atlantics two different nozzle systems were used: 1. The standard Delavan TX-6, which is used commercially for the application 2. Micromax spinning disc controlled droplet applicator (CDA) supplied by the at the 1 gal/ton treatment rate. Micron Corp., Houston, Texas. (Denalls used only Micromax) Chemical Treatment Atlantic: Lot II potatoes (nonbruised and no chemicals) a check treatment. Lot I potatoes (bruised) were divided into 3 treatment lots: one check with no chemicals and two chemical treatments. See Table 9. Denali: Lot II potatoes (nonbruised and no chemicals) were used as a check treatment. Lot I potatoes (bruised) were divided into 2 treatment lots; one check with no chemicals and one chemical treatment. See Table 10. All chemical solutions were used at 0.42 oz/ton Mertect 340F. 1 2 3 4 1 2 3 Nonbruised Bruised Bruised Bruised Nonbruised Bruised Bruised — Check Check Micromax Standard Delavan - — Micromax — 1 gal 3 oz* - — 3 oz* Table 9. Prestorage Chemical and Mechanical Treatments of 1982 Atlantic Potatoes. Treatment Number Total Solution/Ton Mechanical Treatment Nozzle System Table 10. Prestorage Chemical and Mechanical Treatments of 1982 Denali Potatoes. Treatment Number Total Solution/Ton Mechanical Treatment Nozzle System *The 3 oz solution contained 0.42 oz Mertect 340F, 0.64 oz chlorine, and 1.94 oz water. Storage Environment Immediately after treatment, bagging, tagging, etc. all potatoes for this research project were placed in storage cubicles on the MSU campus. Each cubicle contains approximately 350 cubic feet (or 10 cubic meters). The potatoes were suberized for two weeks; one week at 60°F (15.6°C) and 95% r.h. and one week at 55°F (12.8°C) and 95% r.h. After suberization all potatoes were lowered 5°F/week until the desired storage environment of 40, 45, and 50°F and 95% r.h. was obtained. The relative humidity was maintained at 95% by using a hygrodynamics humidity controller with electric vaporizers in each storage cubicle. All cubicles were monitored daily to insure a stable storage environment. Evaluation Weight Loss: All bagged potato samples were weighed after treatment, after two weeks suberization, and at three market quality evaluation dates (83, 142, and 245 days in storage). Weight loss during storage is presented in percent loss and determined by the equation (see page 70). Market Quality Market quality evaluations were made after the potatoes had been in storage for 83, 142, and 245 days. Market quality evaluations involved removing the respective bagged sample from storage, emptying the bag, and examining each individual tuber. The examined tubers were classified as (see page 70). After the potatoes were classified, the nonmarketable potatoes were counted and weighed. Market quality is represented by a percent and is determined by two methods (see page 70). Chip Color Potatoes for chip color evaluation were taken at harvest, after suberization, and 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. Weight Loss is shown in Tables 11-13 and for the Denali potatoes in Tables 14-16. The weight loss data for the 1982 Atlantic potatoes stored at 40, 45, and 50°F DISCUSSION AND RESULTS Excessive sprouting began to occur at the 142 day storage period. Due to the excess sprouting no weight loss is presented at the 245 day evaluation period. Table 11. Weight Loss for 1982 Atlantic Potatoes Stored at 40°F and 95% r.h. Storage Duration Storage Duration Storage Duration Days 83 Wt. Loss % Treatment Number* Storage Duration Days 8 3 WLF .041 .081 .075 .080 Days 142 Wt. Loss % 6.4 8.7 7.4 7.8 *See Table 9 for treatment description for Atlantic potatoes. Table 12. Weight Loss for 1982 Atlantic Potatoes Stored at 45°F and 95% r.h. Storage Duration Storage Duration Storage Duration Days 83 Wt. Loss % Treatment Number Days 142 Wt. Loss % Table 13. Weight Loss for 1982 Atlantic Potatoes Stored at 50°F and 95% r.h. Storage Duration Storage Duration Treatment Number Storage Duration Days 83 Wt. Loss % Days 142 Wt. Loss % Table 14. Weight Loss for 1982 Denali Potatoes Stored at 40°F and 95% r.h. Treatment Number* Storage Duration Days 83 Wt. Loss % Storage Duration Days 142 Wt. Loss % 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 *See Table 10 for treatment description for Denali potatoes. Table 15. Weight Loss for 1982 Denali Potatoes Stored at 45°F and 95% r.h. Storage Duration Days 142 Wt. Loss % Treatment Number 1 2 3 Storage Duration Days 83 Wt. Loss % 5.4 6.3 6.6 Table 16. Weight Loss for 1982 Denali Potatoes Stored at 50°F and 95% r.h. Treatment Number 1 2 3 Storage Duration Days 83Wt. Loss % 4.6 5.7 4.4 Duration Days 83 Storage WLF .055 .069 .053 Storage Duration Storage Duration Days 142 Wt. Loss % 8.1 9.8 8.2 3.4 6.7 6.2 6.7 4.3 6.5 5.4 5.5 5.7 7.0 6.6 6.9 6.0 6.6 7.0 Storage Duration Days 8 3 WLF .052 .079 .065 .066 Storage Duration Days 8 3 WLF .069 .084 .079 .083 Storage Duration Days 8 3 WLF .072 .079 .084 Storage Duration Days 8 3 WLF .065 .076 .079 7.5 10.9 8.5 6.5 8.5 11.4 9.7 9.5 6.8 7.4 8.2 6.1 7.5 7.4 Days142WLF .045 .061 .051 .055 Days142WLF .052 .077 .060 .046 Days142WLF .060 .080 .068 .067 Storage Duration Days142WLF .047 .051 .056 Storage Duration Days142WLF .042 .052 .051 Days142WLF .056 .067 .056 Market Quality Market quality evaluations for the various storage temperatures and durations for the 1982 Atlantic potatoes are shown in Tables 17-19 and for the Denali in Tables 20-22. No market quality data was obtained for the 50°F 245 day storage duration due to the excessive sprouting. No sprout inhibitors are used in the MSU cubicle storage. Market quality evaluations were determined by weight and tuber numbers, however, the weight evaluations are the only ones shown in Tables 17-22. There are many variables that influence market quality of potatoes. These variables include: the prestorage chemical concentrations used; time of application, uniformity of application, rate of flow of potatoes over bin piler, etc. The actual market quality evaluation is also a variable because it is a judgement decision that must be made on each potato. There appears to be a trend developing over our various years of data collection on prestorage treatment. The trend appears to be that Mertect 340F for short duration storage does not show up as well as for durations over 100 days. See Tables 17 and 18. Market quality evaluations are masked in long-term storage due to the sprouting that occurs in the 50° storage environments. These trends need to be further studied and evaluated. This also shows the importance of sprout inhibitors for 50° long-term storage. Table 17. Market Quality (by weight) of Atlantic Potatoes Stored at 40°F and 95% Storage Duration Days Treatment 4 Treatment 2 Treatment 3 Treatment 1 r.h. 83 142 245 Avg. 100 99.6 94.2 98 76.1 78.4 65.2 73.2 75.5 85.8 68.7 77.0 84.0 84.3 64.5 77.6 Table 18. Market Quality (by weight) of Atlantic Potatoes Stored at 45°F. Storage Duration Days Treatment 1 Treatment 2 Treatment 3 83 142 245 Avg. 100 99 91.5 96 76.1 80.0 62.9 80 75.5 80.7 70.4 80 Table 19. Market Quality (by weight) of Atlantic Potatoes Stored at 50°F. Storage Duration Days Treatment 3 Treatment 1 Treatment 2 83 142 Avg. 100 98.5 99 89.5 92.7 91 87.7 85.3 86.5 Treatment 4 84.0 83.4 71.0 83.1 Treatment 4 87.1 86.6 87 Table 20. Market Quality (by weight) of Denali Potatoes Stored at 40°F and 95% r.h. Storage Duration Days Treatment 3 Treatment 1 Treatment 2 83 142 245 Avg. 98.4 97.9 94.5 96.9 78.4 84.0 68.9 77.1 81.1 80.9 85.5 82.5 Table 21. Market Quality (by weight) of Denali Potatoes Stored at 45°F and 95% r.h. Treatment 3 Storage Duration Days Treatment 1 Treatment 2 83 142 245 Avg. 93.3 96.5 85.0 91.6 90.5 86.5 65.1 80.7 90.8 75.9 83.9 83.5 Table 22. Market Quality (by weight) of Denali Potatoes Stored at 50°F and 95% r.h. Treatment 3 Storage Duration Days Treatment 1 Treatment 2 83 143 Avg. 94.8 94.8 94.8 87.3 80.1 83.7 79.9 78.0 79.0 Chip Color Tables 23-28 present the chip color data for the 1982 Atlantic and Denali potatoes. Tables 23-25 show the chip color data for Atlantic potatoes stored for 83, 142, and 245 days. Tables 26-28 show the chip color data for Denali potatoes stored for 83, 142, and 245 days. Chip data was not determined at the 50°F temperature for the 245 day storage duration due to the excessive sprouting and poor potato quality. Table 23. Agtron Chip Color Data for 1982 Atlantic Potatoes Stored at 40°, 45°, and 50°F for 83 days. At Harvest 65+ 65+ 65+ 83 Days Storage 50 - 55 50 - 55 50 - 55 Reconditioning Time Reconditioning Time Reconditioning Time 1 Week 55 - 65 55 - 65 55 - 65 2 Weeks 60+ 60+ 60+ 3 Weeks 65+ 65+ 65+ Original Storage Temp °F 40 45 50 Original Storage Temp °F 40 45 50 Original Storage Temp °F 40 45 Table 24.* Agtron Chip Color Data for 1982 Atlantic Potatoes Stored at 40°, 45°, and 50°F for 142 Days.** Reconditioning Time Reconditioning Time 142 Days Storage 40 - 50 40 - 50 40 - 50 1 Week Reconditioning Time 40 - 50 40 - 50 40 - 50 2 Weeks 45 - 55 45 - 55 45 - 55 3 Weeks 45 - 55 50 - 55 50 - 55 Reconditioning Time 4 Weeks 50 - 55 50 - 60 50 - 60 *Potatoes reconditioned at 5°F/wk. Potato temperatures did not exceed 60°F. **See Table 23 for at harvest Agtron chip color data. Table 25.* Agtron Chip Color Data for 1982 Atlantic Potatoes Stored at 40° and 45°F for 245 Days.** 245 Days Storage 30 - 40 30 - 40 Reconditioning Time Reconditioning Time 1 Week Reconditioning Time 30 - 40 30 - 40 2 Weeks 35 - 45 35 - 45 3 Weeks 35 - 45 35 - 45 4 Weeks Reconditioning Time 35 - 45 35 - 45 *Potatoes reconditioned at 5°F/wk. Potato temperatures did not exceed 60°F. **See Table 23 for at harvest Agtron chip color data. Table 26.* Agtron Chip Color Data for 1982 Denali Potatoes Stored at 40°, 45°, and 50°F for 83 days. At Harvest Temp 40 45 50 *Reconditioned at 5°F/wk. Potato temperatures do not exceed 60°F. 65+ 65+ 65+ 2 Weeks 55 - 60* 60+ 65+ 83 Days Storage 40 - 50 45 - 54 45 - 54 Reconditioning Time 1 Week 45 - 55* 50 - 60 50 - 60 Reconditioning Time Reconditioning Time 3 Weeks 60+ 65+ 65+ Table 27.* Agtron Chip Color Data for 1982 Denali Potatoes Stored at 40°, 45°, and 50°F for 142 days. At Harvest Temp 40 45 50 *Reconditioned at 5°F/wk. Potato temperatures do not exceed 60°F. Reconditioning Time1 Week 40 - 50 45 - 54 45 - 54 65+ 65+ 65+ Reconditioning Time 2 Weeks 45 - 55 50 - 60 50 - 60 Reconditioning Time 3 Weeks 45 - 55 50 - 60 55 - 65 142 Days Storage 40 - 50 45 - 54 45 - 54 Table 28.* Agtron Chip Color Data for 1982 Denali Potatoes Stored at 40° and 45°F for 245 Days. At Harvest Temp 40 45 *Reconditioned at 5°F/wk. Potato temperatures do not exceed 60°F. 65+ 65+ Reconditioning Time1 Week 35 - 44 35 - 44 245 Days Storage 35 - 44 35 - 44 Reconditioning Time 2 Weeks 35 - 44 35 - 44 Reconditioning Time 3 Weeks 35 - 44 35 - 44 Reconditioning Time4 Weeks 50 - 55 50 - 60 60+ Reconditioning Time4 Weeks 35 - 44 35 - 44 QUALITY OF STORED POTATOES DUE TO PRESTORAGE HANDLING, CHEMICAL AND MECHANICAL TREATMENTS, AND STORAGE ENVIRONMENTS (1982 MSU MONONA POTATO PHASE) INTRODUCTION The economic value (market quality) of potatoes varies due to prestorage mechanical and chemical treatments and various storage environments. The overall objective is to try and determine the best combination of prestorage treatments and storage environments to maximize the economic value of potatoes out of extended storage. This report contains the data for the prestorage chemical and mechanical treatment and storage phase for the 1982 Monona potatoes. OBJECTIVES The objectives for the 1982 Monona potato phase of the potato storage research project were: To determine the influence of prestorage mechanical and chemical treatments on the quality of Monona potatoes stored under various environments for extended storage periods. To investigate various rates of prestorage chemical treatments (Mertect 340F and chlorine) and types of application equipment on quality of stored Monona potatoes. To evaluate quality of Monona potatoes stored in commercial bulk bins compared to equivalent potatoes stored in research cubicles at MSU. PROCEDURE Potato Samples The 1982 Monona potatoes were harvested from the Monona plot at Michigan State University’s Montcalm Potato Research Farm, Entrican, Michigan using the one row plot harvester. The potatoes were divided into two lots, Lot I was controlled mechanically bruised by rerunning the potatoes two times over a PTO operated windrower with 700 rpm engine speed. Lot I was designated as bruised potatoes. Lot II was obtained directly off the MSU plot harvester and designated as nonbruised potatoes. Samples from Lot I and II were taken to a commercial processor (Ore-Ida, Greenville), held 48 hours and then given the bruise-free evaluation test. Lot I (bruised) potatoes were given a 65.7% bruise-free evaluation (34.3% bruised). Lot II (nonbruised) potatoes were given a 90.5% bruise-free evaluation (9.5% bruised). Equipment The MSU research conveyor was used for the controlled application of fungicides and bacteriacides. The conveyor controlled the potato volume at 12 tons/hr (about 1/6 - 1/3 the commercial rate). The fungicides and bacteriacides were applied with calibrated equipment. Three different application nozzles were used: 1) the standard Delavan TX-6 nozzle used commercially for the recommended 1 gallon fungicide treatment rate, 2) the Micromax, and 3) Mantis II spinning disc controlled droplet applicators. They were supplied by Micron Corp., Houston, Texas. 1 2 3 4 5 6 Nozzle System Check Check Micromax Mantix II Mantis II 1 gal. 3 oz. 3 oz. 2 oz. Chemical Treatment The Lot II potatoes (nonbruised) were a check treatment (no chemical). Lot I potatoes (bruised) were divided into 5 treatment lots: one check (no chemical) and four different chemical treatments. See Table 29 for detailed description of the six treatments. Table 29. Prestorage Chemical Application Treatments on 1982 Monona Potatoes. * Treatment - Total Solution/Ton Standard Delavan - *Treatments 3-5 used 0.42 oz/ton Mertect 340F, .64 oz/ton chlorine (5.25% active chlorine ingredient) plus water. Treatment 6 used .42 oz/ton of Mertect 340F, 0.64 oz chlorine, and 1.06 oz/ton water. Mertect 340F contains 42.78% active ingredients of 2-(4-Thiazolyl) Benzimidazole (TBZ). Storage Environment Immediately after treatment, bagging, tagging, etc. all potatoes for this research project were placed in storage cubicles on the MSU campus. Samples from all six treatments were also placed in the center of a commercial potato storage (Bin #10 Chief Chips Storage, Edmore, Michigan). The Michigan State University 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 storage temperatures were lowered 5°F/week until the desired storage environments of 40°, 45°, 50°F and 95% r.h. were reached in the MSU cubicles and 45°F and 95% r.h. in the commercial storage. The relative humidity was maintained at 95% by using hygrodynamics humidity controller with electric vaporizers in each storage cubicle. All cubicles were monitored daily to insure a stable storage environment. Evaluation Residue: 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. Weight Loss All MSU stored bagged potato samples were weighed after treatment, after two weeks suberization, and at the three market quality evaluation dates (83, 142, and 245 days storage). The weight loss for the samples in the commercial storage was determined when the storage was emptied after 190 days of storage. Market Quality Market quality evaluations were made at three times during storage, December 22, 1982 (83 days storage), February 17, 1983 (142 days storage), and May 21, 1983 (245 days storage). The potatoes in the commercial storage were evaluated when the storage was emptied after 190 days storage. Market quality evaluations involved removal of a respective bag from storage, emptying the bag, and examining each individual tuber. Chip Color Chip color samples were taken at harvest, after suberization, and at each of the three evaluation dates. Potato samples were fried in vegetable oil at 365°F for 105-135 seconds. Samples that did not get a 60 or higher reading on the Agtron index were reconditioned by increasing the temperature 5°F/week until the desired chip color was reached or potato quality could no longer be maintained. Potato storage temperatures did not exceed 60°F. DISCUSSION AND RESULTS Weight Loss Weight loss data for the 1982 Monona potatoes are shown in Tables 30-33. Tables 30-32 compare the weight loss between bruised and nonbruised potatoes stored in the MSU cubicles at 40, 45, and 50°F for 83, 142, and 245 days. Table 33 shows the weight loss data for the Monona potatoes stored in bin #10 Chief Chips Storage, Edmore, Michigan. Nonbruised potatoes for all treatments have slightly less weight loss than bruised potatoes. This is expected due to the increased weight loss during suberization of the bruised potatoes. However, Tables 30-33 show that with good suberization and storage at 95% r.h. there is less than 2% weight loss difference between bruised and nonbruised potatoes even after 245 days in storage. The weight loss factor (WLF) is an important factor for growers. The WLF is a "tool” that enables a grower to economically consider holding or selling a bin of potatoes. Extended storage normally means an increased selling price per hundredweight (cwt); however, weight loss and market quality degradation due to extended storage may dictate selling. The ”WLF tool” can be used as an aid in this decision. To use the WLF multiply the days in storage times the appropriate WLF closest to the storage duration. From the data on weight loss there is no clear correlation between the six treatments, chemical formulations, and application methods. It is shown, however, that there is less weight loss for nonbruised potatoes than bruised potatoes for a given storage duration. As storage duration increases, the amount of weight loss increases for a given controlled environment. Table 30. Weight Loss Data for 1982 Monona Potatoes Stored in the MSU Cubicles at 40°F and 95% r.h. Treatment Avg. Bruised Storage Duration Days 83 % 5.3 6.6 6.4 5.1 5.3 5.4 5.8 Storage Duration Days83WLF .064 .080 .078 .061 .064 .065 .070 Storage Duration Days 142 % 6.3 6.4 6.3 6.5 6.8 6.6 6.5 Storage Duration Days 142 WLF .044 .045 .044 .046 .048 .046 .046 Storage Duration Days245% 8.5 7.8 10.5 10.0 9.7 8.5 9.3 Storage Duration Days245WLF .035 .031 .043 .041 .039 .035 .038 1 2 3 4 5 6 1 2 3 4 5 6 Table 31. Weight Loss Data for 1982 Monona Potatoes Stored in the MSU Cubicles at 45°F and 95% r.h. Treatment Avg. Bruised Storage Duration Days 83% 6.2 6.7 5.0 5.0 5.4 5.8 5.6 Storage Duration Days83WLF .075 .081 .061 .060 .065 .070 .067 Storage Duration Days 142 % 7.2 8.9 7.6 7.0 7.0 7.8 7.7 Storage Duration Days 142 WLF .051 .063 .054 .050 .050 .055 .054 Storage Duration Days245% 11.8 14.2 13.7 13.0 11.8 14.1 13.4 Storage Duration Days245WLF .048 .058 .056 .053 .048 .058 .055 Table 32.* Weight Loss Data for 1982 Monona Potatoes Stored in the MSU Cubicles at 50°F and 95% r.h. Storage Storage Duration Days 142 Duration Days 83 Storage Duration Days 142 WLF Treatment 1 2 3 4 5 6 .052 .059 .047 .050 .050 .061 Avg. Bruised .053 *Since no sprout inhibitors were used there was excessive sprouting at the 245 day storage duration and thus no weight loss data was calculated for the 50°F Monona potatoes. % 7.4 8.4 6.7 7.1 7.1 8.6 7.6 Storage Duration Days83% 5.1 6.3 5.1 4.5 5.3 5.7 5.4 Table 33. Weight Loss Data for 1982 Monona Potatoes Stored in the Chief Chips Storage, Edmore, Michigan at 45°F and 95% r.h. for 190 Days. WLF .061 .076 .062 .055 .064 .068 .065 % 5.0 4.8 6.2 5.3 5.3 5.9 5.5 Treatment 1 2 3 4 5 6 Avg. Bruised WLF .026 .025 .033 .028 .078 .031 .029 Market Quality and Deposition Market quality and deposition for the 1982 Monona potatoes are shown in Tables 34-37. Tables 34-36 compare market quality, deposition, treatments, and storage duration for the 1982 Monona potatoes stored in the MSU cubicles. Table 37 compares market quality, deposition, treatments, and storage duration for the 1982 Monona potatoes stored in the center of a commercial potato storage (bin #10, Chief Chips). Table 37 shows that there is a difference in market quality between the nontreated and nonbruised checks (73% to 93%), however, the prestorage chemical treatments appear to be less effective on improvement of market quality than in previous years. The Micromax showed a 11% improvement in market quality over the bruised nontreated check (75% to 84%). The other three prestorage treatments show very little variation, however, the average prestorage chemical treatments show a gain in market quality over equivalently bruised nontreated potatoes. As stated previously in this report, there are problems in most any research and repeatings (replications) are essential—during the year and various years. During 1982 MSU cubicle storage we evidenced cubicle temperature failure during suberization and twice during the storage duration temperatures were found during the daily checks to be off 5°F or more. Murphy’s Law says that anything that can fall will fail. Table 34. Market Quality and Deposition for 1982 Monona Potatoes Stored in the MSU Cubicles at 40°F and 95% r.h. Storage Duration Days 83 142 245 Evaluation Dates in 1982/83 12/20 2/17 5/31 Treatment*1 99.2 98.7 97.1 — Treatment*2 91.7 90.3 93.1 — Treatment* 3 92.6 89.3 87.4 1.90 Treatment* 4 93.1 91.1 86.5 6.73 Treatment*5 95.0 91.7 90.2 10.67 Treatment*6 94.1 93.4 90.9 2.95 Deposition ppm *See Table 29 for a detailed description of treatments. empty table cell Table 35. Market Quality and Deposition for 1982 Monona Potatoes Stored in the MSU Cubicles at 45°F and 95% r.h. Storage Duration Days 83 142 245 Evaluation Dates in 1982/83 12/20 2/17 5/31 Treatment*1 99.8 97.9 96.5 — Treatment*2 96.5 93.1 86.1 — Treatment* 3 99.3 89.9 82.4 1.90 Treatment* 4 98.0 88.3 80.1 6.73 Treatment*5 96.4 91.1 84.0 10.67 Treatment*6 94.1 93.4 90.9 2.95 Deposition ppm *See Table 29 for a detailed description of treatments. empty table cell Table 36. Market Quality and Deposition for 1982 Monona Potatoes Stored in the MSU Cubicles at 50°F and 95% r.h. Storage Duration Days 83 142 Evaluation Dates in 1982/83 12/20 2/17 Treatment*1 99.1 97.8 — Treatment*2 93.2 89.6 — Treatment* Treatment* 3 96.6 87.6 1.90 4 98.6 87.2 6.73 Treatment*5 97.3 93.2 10.67 Treatment*6 96.9 92.4 2.95 Deposition ppm empty table cell *See Table 29 for a detailed description of treatments. Table 37. Market Quality for 1982 Monona Potatoes Stored at 45°F and 95% r.h. for 190 Days in the Center of Bin #10, Chief Chips Commercial Potato Storage, Edmore, Michigan. Treatment Number* Market Quality % Good by Weight Deposition ppm Going into Storage 1 2 3 4 5 6 93.0 73.2 76.3 84.3 74.7 73.1 — — 1.90 6.73 10.67 2.95 *See Table 29 for detailed description of treatments. Chip Color Tables 38-40 show the Agtron chip color data for the 1982 Monona potatoes stored in the MSU cubicles. Table 41 shows the chip color data for the MSU potatoes stored in the center of bin #10, Chief Chips Storage, Edmore, Michigan The 1982 data on Agtron chip color appears to indicate that Monona potatoes stored at 40, 45, and 50°F will recondition to an acceptable Agtron color better than Atlantic or Denali. Table 38. Agtron chip color data for 1982 Monona potatoes stored in the MSU cubicles for 83 days and reconditioned at an increasing temperature of 5°F/Week.* empty table cell At Evaluation 40° 45° 50° *Agtron chip color at harvest was 65+. 50 - 55 50 - 55 50 - 55 Reconditioning Time 1 Week Reconditioning Time 55 - 64 55 - 64 60+ 2 Weeks 60+ 60+ 60+ 3 Weeks Reconditioning Time 60+ 65+ 65+ Table 39. Agtron Chip Color Data for 1982 Monona Potatoes Stored in the MSU Cubicles for 142 days and reconditioned at an increasing temperature of 5°F/week. 5 Weeks Reconditioning Time 60+ 60+ 60+ empty table cell At Evaluation 40° 45° 50° *Agtron chip color at harvest was 65+. 50 - 55 50 - 55 50 - 55 1 Week Reconditioning Time 50 - 55 50 - 55 50 - 55 2 Weeks 55 - 64 55 - 64 55 - 64 Reconditioning Time Reconditioning Time 3 Weeks 55 - 64 55 - 64 55 - 64 Reconditioning Time 4 Weeks 55 - 64 55 - 64 55 - 64 Table 40. Agtron Chip Color Data for 1982 Monona Potatoes Stored in the MSU Cubicles for 245 days and reconditioned at increasing temperature of 5°F/week.* 40° 45° 50o** *Agtron chip color at harvest was 65+. **Poor potato quality due to excessive sprouting. For this reason no further chip 50 - 55 50 - 55 Poor potato quality 55 - 64 55 - 64 Poor potato quality 50 - 55 50 - 55 50 - 55 Poor potato quality 55 - 64 55 - 64 55 - 64 55 - 64 Poor potato quality data was obtained. Table 41. Chip Color Data for 1982 Monona Potatoes Stored in the Center of the Chief Chips Commercial Potato Storage (Bin #10) for 190 days and reconditioned at increasing temperatures of 5°F/week. At 190 Days Storage 1 Week Recondition Storage Temperature 45°F At Harvest 65+ 55 - 64 60+ CONCLUSIONS 1. 2. 3. There is an interaction among these storage related factors; bruised and nonbruised potatoes, storage duration, market quality, and TBZ deposition. The various chemical formulations used on these Monona potatoes showed no evidence of affecting weight loss on equivalently treated and stored potatoes. The out-of-storage market quality of bruised potatoes was lower than the market quality of nonbruised potatoes under equivalent storage conditions. 4. Deposition is influenced by application equipment, however, above a certain level market quality is not improved. CONTROLLED DROPLET APPLICATION OF MERTECT 340F IN A COMMERCIAL POTATO STORAGE (Lennard & Sons, Samaria, Ml) INTRODUCTION During October 7 to 11, 1982 fungicide/bacteriacides (Mertect 34OF and chlorine) were applied by controlled droplet application (CDA equipment) to Denali potatoes going into a commercial potato storage at Wayne Lennard and Sons, Samaria, Michigan. One entire storage bin (approximately 12,000 cwt) was treated. PROCEDURE Equipment A Mantis II CDA nozzle was mounted on the Lennard bin piler over a cleaning bed just after the sorting table. The pump used for the CDA system was a high-speed centrifugal pump. Both the pump and the nozzle were supplied by the Micron Corp., Houston, Texas. The equipment was calibrated for a 45 ton/hr bulk trunk unloading rate and a chemical solution was applied with the CDA equipment at a rate of 3 oz per ton. Chemical Solution A 3 oz/ton solution rate was used on the project. The 3 oz solution contained 0.42 oz of Mertect 340F, 0.64 oz chlorine (5.25% active ingredient), and 1.94 oz water. Potato Samples Forty-three potato samples (approximately 25 lbs each) were obtained from two field truck loads during the first day of filling the storage. Seven samples were sent to Merck, Inc. for a TBZ deposition analysis. Twenty-four samples (nine nontreated check samples and 15 treated samples) were bagged, tagged, and placed into the middle of the potato pile at the west, east, and center locations of the storage. Twelve samples, 3 checks and 9 treated, were tagged, weighed, and placed into three MSU storage cubicles. The MSU cubicle stored potatoes were suberized at 60°F and 951 r.h. for 10 days and then the temperature was reduced 5°F/wk until the desired pulp temperatures of 40°, 45°, and 50°F and 95% r.h. were reached. EVALUATION Residue 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, Inc., Rahway, New Jersey. Weight Loss All bagged potato samples were weighed after treatment; after two weeks suberization; at the market quality evaluation date (239 days in storage). Weight loss during storage is represented by a percent using the following equation (see page 70). Market Quality A market quality evaluation was made at 239 days in storage. Market quality evaluation involved removal of a respective bag from storage, emptying the bag, and examining each individual tuber. Examined tubers were classified (see page 70). After the potatoes were classified, the non-marketable potatoes were counted and weighed. Marketable quality is represented by a percent and is determined by two methods (see page 70). RESULTS AND DISCUSSION Weight Loss Weight loss data for the Lennard Denali potatoes stored at Michigan State University is shown in Tables 42-44. The potatoes were stored at 40°, 45°, and 50°F and 95% r.h. Weight loss data was not taken after 132 days in storage due to excessive sprouting. (Potatoes stored in MSU cubicles cannot be gased for sprout inhibition). Note in these three tables that 45°F shows slightly less weight loss than the 40° and 50° storage temperature. Table 42. Weight Loss Data for 1982 MSU Stored Lennard Denali Potatoes at 40°F and Table 43. Weight Loss Data for 1982 MSU Stored Lennard Denali Potatoes at 45°F and Storage Duration Days 73 Wt. Loss % 7.0 7.5 Storage Duration Days 73 WLF .096 .099 Storage Duration Days 132 Wt. Loss % 8.1 8.3 Storage Duration Days 132 WLF .061 .063 Storage Duration Days 73 Wt. Loss % 6.1 7.6 Storage Duration Days 73 WLF .083 .099 Storage Duration Days 132 Wt. Loss % 7.1 8.0 Storage Duration Days 132WLF .054 .060 Table 44. Weight Loss Data for 1982 MSU Stored Lennard Denali Potatoes at 50°F and Storage Duration Days 73 Wt. Loss % 6.9 7.5 Storage Duration Days 73 WLF .095 .098 Storage Duration Days 132 Wt. Loss % 9.4 8.9 Storage Duration Days132WLF .071 .067 Tables 45 and 46 present the market quality data for the commercial storage and the MSU stored Lennard Denali potatoes, respectively. Table 45. Market Quality Data for the 1982 Commercially Stored Lennard Grown Denali Potatoes. Potatoes were Stored for 245 Days at 50°F. Market Quality Treatment Non-treated Treated Treatment Non-treated Treated 95% r.h. 95% r.h. 95% r.h. Treatment Non-treated Treated Market Quality Treatment East check* East treated** Center check treated Center West check treated West Check average Treated average 86.9 89.0 77.9 89.9 84.3 83.4 83.0 87.4 *Check potato samples were collected at the end of the bin piler (no chemical treatment). **Treated potatoes were collected the same as the check potatoes, however, these potatoes were treated at a chemical solution calibration rate of 3 oz/ton. Table 46. Market Quality Data for the 1982 Lennard Grown Denali Potatoes Stored in the MSU Cubicles for 245 Days. Residue and treated at Wayne Lennard and Sons. Table 47 shows the TBZ residue for the 1982 Denali potatoes commercially grown Table 47. TBZ Residue Analysis Results for the 1982 Lennard Farms Commercially Treated Denali Potatoes. Treated Samples * *Treated samples were collected from the end of the bin piler during the unloading of two field trucks. The chemical solution application rate was calibrated for a 3 oz/ton application rate and a 45 ton/hour unloading rate. **Parts per million. Treatment 40° check 40° treated 45° check 45° treated 50° check 50° treated Check average Treated average 1 2 3 4 5 6 Avg. Market Quality 78.9 92.6 89.0 86.1 67.5 84.8 74.5 87.8 ** Residue 3.1 - 3.32 5.08 - 5.15 3.62 - 3.87 6.94 - 7.86 6.98 - 7.64 9.07 - 9.62 5.79 - 6.24 CORN HYBRIDS, PLANT POPULATIONS, AND IRRIGATION E.C. Rossman and Keith Dysinger Department of Crop and Soil Sciences Performance data for 59 commercial corn hybrids evaluated in 1983 with and without irrigation are presented in Table 1 along with two and three year averages for those tested in 1982 and 1981. One inch of water was applied through a sprinkler system on each of 7 dates (July 5, 12, 18, 27, August 9, 19, 29) for a total of 7 inches of irrigation. Rainfall was: April = 3.47", May = 4.46", June = 1.9", July = 2.44", August = 2.21", September = 5.34", October = 3.26". Irrigated yields averaged 85.0 bushels more than nonirrigated - 151.4 vs. 66.4, an increase of 128%. Hybrids ranged from 95.7 to 194.7 with irrigation and 36.5 to 90.5 without irrigation. Hybrids significantly better than average yield (arranged in order of increasing grain moisture content at harvest) are listed below. Fifteen of the 21 hybrids were in the highest yielding group for both irrigated and nonirrigated plots. Irrigated Pioneer 3901 Funk 29097 Great Lakes 82351 DeKalb-Pfizer EX-2120 Pioneer 3744 Super Crost 1940 DeKalb-Pfizer DK-484 King K4422 Dairyland DX1003 Funk G-4342 DeKalb-Pfizer T1000 Stauffer Seeds S5340 Great Lakes GL-522 Dairyland DX1006 P-A-G SX239 Stauffer Seeds S5650 Andersons PSX105 MFI 1812 Stauffer Seeds S5260 Not Irrigated Pioneer 3901 Funk 29097 Great Lakes 82351 Pioneer 3744 DeKalb-Pfizer DK-484 Pioneer 3747 King K4422 Golden Harvest H-2480 Dairyland DX1003 Stauffer Seeds S5340 Great Lakes GL-522 Dairyland DX1006 P-A-G SX239 Stauffer Seeds S5650 Andersons PSX105 MFI 1812 Stauffer Seeds S5266 The correlation of irrigated with nonirrigated yields was highly significant, .722, indicating that hybrids tended to respond alike in both situations. During the 16-year period, 1968-1983, 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 16-year period, 1968-1983, are given in Table 2. The average yielding hybrids have yielded 47 more bushels when irrigated. The highest yielding hybrids have responded with 60 bushels added yield while the lowest yielding hybrids have given only 31 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. Stalk lodging was equal for both situations — 9.1% for irrigation and 8.9% without irrigation. In most (but not all) of the previous years, there was 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 16 years, 1968-1983, Table 3. Over the 16-year period, a harvest plant population of 23,310 has given the highest average yield (166 bushels per acre) when irrigated while 19,340 has given the highest yield (108 bushels) without irrigation. The 19,340 population irrigated has given the highest yield in 12 out of 16 years (1973, 1979, 1981 and 1983 being the exceptions). The irrigated yields in 1983 were 154, 170, 179 and 182 for harvest populations of 15,270, 19,340, 23,310 and 27,470, respectively. The 16-year average increase due to irrigation is 66 bushels per acre at the 23,310 population. Nonirrigated yields were 69, 74, 66 and 52 for the same four populations in 1983. Stalk lodging has increased with plant population. In 1983, there was 3-4 times more lodging at 27,470 than there was at 15,270. Moisture content of grain at harvest has averaged 1-2% higher for the two higher populations. TABLE 1 HYBRID (BRAND-VARIETY) FUNK 0008X PAYCO SX431 GREAT LAKES GL-381 MFI 1492 DEKALB-PFIZER T891 PAYCO SX599 P-A-G SX155 DAIRYLAND DX1094 DIARYLAND DX1091 MCKENZIE 858 ANDERSONS PSX93 STANTON SX 1090 RUPP XR1490 SUPER CROST 1542 GREAT LAKES GL-422 PIONEER X7064 *+PIONEER 3901 GARNO S-90 STANTON SX 1095 *+FUNK 29097 DAIRYLAND DX1096 PAYCO SX620 DEKALB-PFIZER XL-8 GREAT LAKES 81237 *+GREAT LAKES 82351 * DEKALB-PFIZER EX-2120 DAIRYLAND DX1093 STANTON SX 10100 JACQUES JX97 *+PIONEER 3744 * SUPER CROST 1940 MCKENZIE 411 DEKALB-PFIZER T950 MFI 1776 *+DEKALB-PFIZER DK-484 WOLVERINE W166 +PIONEER 3747 *+KING K4422 KING K4423 +GOLDEN HARVEST H-2480 NORTH CENTRAL MICHIGAN % Moisture 1983 Montcalm County Trial - Irrigated vs. Not Irrigated ONE. TWO. THREE YEAR AVERAGES - 1983, 1982, 1981 BUSHELS PER ACRE3 % Moisture Years 2 Not YR - - BUSHELS PER ACRE 2 Years Irrig - - - -- -- - BUSHELS PER ACRE 198 3 BUSHELS PER ACRE 3 Years Irrig BUSHELS PER ACRE 198 3 BUSHELS PER ACRE 2 Years Not Irrig Not ZONE 3 % STALK LODGING % STALK 198 3 Not LODGING1983Irrig % STALK % STALK LODGING 2 LODGING3 Years Years Not Irr ---- ---- % STALK LODGING 3 Years Irr % STALK LODGING 2 Years Not 23.8 9.5 11.7 9.4 10.1 5.1 4.0 6.1 4.8 12.7 5.9 2.2 8.1 11.4 5.8 7.0 6.9 7.9 5.6 11.0 3.0 10. 1 8. 1 4.5 4.4 7.5 10.9 17.2 12.5 5.8 7.8 6.0 7.5 11.4 11.4 22.6 8.8 6.4 6.2 9.8 10.9 8 9.3 13.7 - - 16.3 - - 19.4 - - 3 9.9 18.8 - - 4 8.9 -- 6.1 10.8 - - - - 6.0 1 5.0 - - 7 4 7.8 - - 6 8.2 - - 5.2 13.7 7.9 9.4 10.4 5 6 4 - - 5 8.5 12.5 - - 6.7 6 5.8 - - - - 5.7 21.2 4 8.0 - - 13 9.0 8 4.5 4 1.5 - - - - 6 - - - - - - - - - - - - - - 5.6 4.4 8.7 8.7 8.4 11.3 5.9 3.7 6.7 13.2 - - - - - - 10 -- -- - - - - - - - - - - - - - - - - 10 - - 8 - - - - - - 6 - - - - 9 - - 10 10 12 - - 9 - - 6 - - - - 15 - - 1 1 9 5 - - - - 10 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -- - - - - - - - - - - - -- 5 4 5 - - - - - - 8 - - 7 8 - - - - - - - - - - - - - - 7 1 1 - - — - - - - - - - - - - — - - - - - - 3 5 - - - - 8 - - - - 6 - - - - - - - - - - - - - - - - - - - - - - - - - - - % Moisture3 YR - - 23 - - - - - - - - - - - - - - - - 23 - - - - 23 - - - - - - - - - - - - 22 - - - - - - - - - - 23 - - 23 - - - - 23 23 24 23 24 - - - - - - 23 24 - - - - 24 - - - - - - - - - - 25 - - - - - - 26 - - 24 - - 25 25 22.6 23.4 23.5 23.8 23.9 24.0 24.3 24.3 24.3 24.4 24.4 24.4 24.7 24.9 25.0 25.0 25.1 25.4 25.4 25.5 25.5 25.5 25.7 26.0 26.2 26.6 26.6 26.9 27.1 27.1 - - 27.5 - - 27.5 27.7 26 - - 27.7 27.8 - - - - - - - - - - - - 27.9 28.1 28.1 28.1 28.2 25 - - - - - - - - - - - - - - - - - - 97.5 102.6 109.8 121.3 95.7 108 38.9 45.3 43.0 - - 46.4 - - 36.5 - - 112.3 1 10.5 124.6 117.5 120.9 140.9 129.3 121.4 101.2 146.0 142.5 170.6 143.9 158.0 176.0 143.6 152.0 130.4 160.8 170.2 168.8 132.7 150.6 149. 1 184.7 167.4 164.9 164.6 157.6 194.7 141.9 157.5 182.8 164.6 164.0 114 134 47.3 39.5 - - 59.3 55.8 - - 41.3 - - - - 46.7 54.5 64.1 - - 47.7 - - 66.7 133 154 - - 61.9 75.7 61.9 63.3 75.5 - - 167 154 162 150 63.5 60.5 - - 50.5 65.5 - - 76.8 - - 132 157 62.4 55.2 - - 65. 1 63.2 90.5 148 150 172 - - 70.0 64.4 - - 148 66.3 70.9 - - 83.2 - - - - 62.9 75.9 - - 82.6 - - 69.2 - - 74.3 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 69 - - - - - - - - - - - - - - - - - - - - - - - - - - 69 - - 82 - - - - - - 82 - - - - 95 - - 144 95 - - - - 154 143 100 94 95 - - - - - - 99 94 - - -- 90 141 94 - - - - - - - - 93 - - - - - - 78 - - - - - - - - - - - - - - - - - - 93 — — 87 — - - 108 108 - - - - - - - - 158 - - - - 84 - - - - - - - - - - - - - - 130 - - - - - - - - - - - - - - 79 - - - - - - - - - - - - - - NORTH CENTRAL MICHIGAN Montcalm County Trial - Irrigated vs. Not Irrigated % Moisture 1983 ONE, TWO, THREE YEAR AVERAGES - 1983, 1982, 1981 % Moisture 2 YR BUSHELS PER ACRE 2 Years Irrig BUSHELS PER ACRE 198 3 Not BUSHELS PER ACRE 2 Years Not BUSHELS PER ACRE 3 Years Irrig BUSHELS PER ACRE3 YearsNot PER ACRE1983Irrig % Moisture3 YR BUSHELS ZONE 3 % STALK LODGING 1983Irrig 198 % STALK LODGING 3 Not % STALK LODGING 2 Years Irr % STALK LODGING 2 Years Not % STALK LODGING 3 Years Irr % STALK LODGING3 Years Not TABLE 1 HYBRID (BRAND-VARIETY) SUPER CROST 2396 FUNK 2OO8X GREAT LAKES GL-466 *+DIARYLAND DX1OO3 * FUNK G-4342 *+STAUFFER SEEDS S534O P-A-G SX193 * DEKALB-PFIZER T1OOO GOLDEN HARVEST H-2380 *+GREAT LAKES GL-522 PAYCO SX872 *+DAIRYLAND DX1006 *+STAUFFER SEEDS S565O *+P-A-G SX239 JACQUES JX151 *+ANDERSONS PSX1O5 P-A-G EXP. 111571 *+MFI 1812 *+STAUFFER SEEDS S526O AVERAGE RANGE 26 28.4 28.5 — — 28.5 28.5 28.6 — — 26 25 — — 28.8 28.8 — 28.8 28.8 28.9 — 27 25 27 — 29.8 30.0 30.2 30.2 — 30.3 — 27 — 28 — — 27 — — 31 .0 — 31.3 — 31.6 — — 32.2 29 — 27.0 22.6 TO 32.2 25 22 TO 29 26 25 25 27 — 27 29 25 23 TO 29 166.6 164.0 154.5 185.2 168.8 182.7 129.4 169.0 163.4 175.4 150.7 182.9 187.5 179.1 164.7 170.2 165.2 172.6 184.1 69.0 70.3 — 73.0 81.1 68.5 — — 79.7 63.8 — 68.7 72.9 83.9 — 64.4 79.1 87.6 79.1 — 71.6 — 82.9 72.5 — 75.3 — 87.5 151.4 66.4 95.7 TO 194.7 38.9 TO 90.5 163 156 169 168 161 176 169 171 157 184 154 108 TO 184 9 152 144 154 94 96 98 — — — — 97 99 — 109 153 160 — 94 — 108 — — 92 — — — — — — — — — — — — — 97 92 98 95 106 — — — — — — — — — — — — — 113 93 69 TO 113 6 158 149 130 TO 160 7 104 97 79 TO 108 5 16.7 4.9 14.3 10.2 2. 1 2.2 18.4 11.3 10.4 9.4 9.0 10.7 8.3 7.2 14.2 13.0 2.9 6.7 10.8 12.2 10.2 — 10.5 6.6 4.5 — — 11.9 11.4 — 4.4 8.3 3.8 — 8.5 11.5 2.2 4.4 — 11.2 — 12.9 7.0 — 11.5 — 3.7 — — — — — — — — 11 9 6 8 8 5 9 4 10 6 6 12 8 8 — — — — 6 9 6 — — — 14 4 — — — — — 12 4 9 4 TO 15 11 9 7 9 7 6 — — — — 7 7 — — 5 3 — — — — — — — — — 5 6 3 TO 9 4 7 4 TO 1 1 9. 1 8.9 2. 1 TO 23.8 1.5 TO 21.2 — — 1 TO 13 — — — — LEAST SIGNIFICANT DIFFERENCE 1.9 1.1 0.7 14.9 7.5 * SIGNIFICANTLY BETTER THAN AVERAGE YIELD. IRRIGATED, IN 1983 + SIGNIFICANTLY BETTER THAN AVERAGE YIELD, NOT IRRIGATED, IN 1983 empty table cell 1983 1982 Planted Harvested Soil Type Previous crop Population Rows Fertilizer Irrigation Soil test - pH P Soil test Soil test K May 6 October 24 Montcalm - McBride sandy loam Potatoes 21.400 30" 330-125-125 7 inches 5.8 417 (very high) 202 (medium) May 6 November 3 Montcalm - McBride sandy loam Alfalfa 21.000 30" 342-139-139 4 inches 5.6 562 (very high) 251 (high) 1981 May 2 November 6 Mon team - McBride sandy loam Alfalfa 20.850 30" 323-143-143 4 inches 5.9 512 (very high) 284 (high) Farm Cooperator: Theron Comden, Montcalm Research Farm, Lakeview County Extension Director: William Carpenter. Stanton (1983) dames Crosby. Stanton (1982,1981) TABLE 2. Average, highest and lowest yields for corn hybrids irrigated and not irrigated for 16 years, 1968 - 1983. Year 1983 1982 1981 1980 1979 1978 1977 1976 1975 1974 1973 1972 1971 1970 1969 1968 No. of Hybrids Tested 59 82 90 71 83 73 74 80 75 76 72 72 56 64 63 56 empty table cell AVERAGE AVERAGE AVER AGE Irrigated Not Irrigated HIGHEST HIGHEST Irrigated Not Irrigated 151 146 115 126 109 144 125 156 154 112 114 157 163 144 146 136 138 66 113 87 114 67 88 73 72 125 103 101 137 28 103 86 96 91 195 183 141 167 142 186 158 183 207 134 138 206 211 194 185 182 176 91 139 111 156 92 112 88 93 157 122 120 179 42 128 109 123 116 Irrigated 96 109 85 74 67 92 89 120 106 65 78 99 91 95 97 92 91 LOWEST LOWEST Not Irrigated 37 83 62 65 42 61 56 49 80 58 73 91 11 70 56 65 60 TABLE 3. Average yield at four plant populations irrigated and not irrigated for 16 years, 1968 - 1983. Year 1983 1982 1981 1980 1979 1978 1977 1976 1975 1974 1973 1972 1971 1970 1969 1968 AVERAGE 15,270 Irrigated 154 150 122 133 123 146 141 153 158 118 108 152 173 122 126 144 140 15,270 Not Irrigated 19,340 19,340 Irrigated Not Irrigated 23,310 23,310 Irrigated Not Irrigated 27,470 27,470 Irrigated Not Irrigated 69 120 93 123 77 92 74 72 136 100 97 132 37 91 91 114 96 170 168 132 146 140 164 152 174 183 130 134 187 189 144 158 169 159 74 131 102 135 87 110 81 84 164 111 116 159 35 112 109 130 108 179 177 130 150 138 175 160 181 196 135 128 191 191 158 173 193 166 66 124 94 131 83 100 70 81 151 98 106 149 20 93 96 107 100 182 176 119 141 131 165 150 161 172 120 108 161 181 151 148 178 152 52 117 86 124 78 94 69 68 146 94 102 144 11 85 86 89 94 1983 DRY BEAN VARIETY AND STRAIN EVALUATION TRIALS J. Taylor, J. Kelly, A. Ghaderi, and M.W. Adams Test #3220. Large Seeded Yield Trial, Montcalm - 1983. This trial was conducted at Montcalm Research Farm to evaluate yield potential of new and standard kidney and cranberry bean varieties. The trial was highly variable with a high C.V.=21.9%. Overall the bush cranberry lines were the highest yielding entries, with entry nos. 1, 6, 4 from MSU and nos. 11 and 10 from University of Idaho showing the most potential. All these breeding lines carry BCMV resistance and the MSU lines 1, 6, 4 had a desirable larger seed size of 52-56 g/100 seeds. The UI lines tended to be smaller, with seed size equivalent to Cran-028 seed size. The yield potential of new LRK lines from University of California and the USDA program in Washington appeared to have no yield advantage over the standard LRK varieties. Test #3221. Preliminary DRK Bean Yield Trial, Montcalm - 1983. Trial 3221, consisted of 49 entries of which only 25 entries were harvested including the 3 check varieties - Montcalm, Charlevoix and Isabella. The test was highly variable as indicated by the high CV value of 25.2. None of the breeding lines outyielding the standard cultivar Montcalm, but with the large LSD value of 528 pounds/acre, 17 of the lines were not significantly different from the Montcalm check. A number of lines had a significantly lower seed size than the 52 g/100 seed size of the 3 checks. Additional yield testing of 8 lines with satisfactory seed size will be required because of high variability within this particular test. MSU BEAN PROGRAM U1111 ADVANCED LINE TESTING MONTCALM 3220 LARGE SEEDED NURSERY. MONTCALM PLOTENTRY ACCORIG NO SOURCE PEDIGREE 05 CRAN028 10 08 14 K74002 MONT 12 K60001 CHAR C70001 C81009 MVR CRAN 101 102 103 12 I820408922 UI 104 03 C81003424 ANDY 105 106 07 C81008T HORT 422 ANDY 10701 C81001 I82038 8920 UI 108 10904 C81004425 ANDY 07009 UI 11009 I82037 111 11206C66001MICRAN 11302 C81002423 ANDY I82039 8921 UI 114 11520 K7700270688 11624 I82003 RY CN 117 11817K74001 MEC 11915 I81099SB NL 120 12118 I811039482 ANDY 122 26 I82029 NW126 USDA-WA 123 12423 I81061SAC SVN 125 16 K66001 MAN 12627 I820282602 UCD 127 12825 I82030NW341 USDA-WA I82027 2204 UCD I81058 RKLD CN 19 K77001 70684 K77003 70700 11 28 22 21 CRAN028 MVR CRAN 8922 UI 424 ANDY MONT T HORT 422 ANDY 425 ANDY 8920 UI 07009 UI CHAR empty table cell 423 ANDY 8921 UI RKLD/MEC.ISA RY CN 2204 UCD MEC SB NL RKLD CN 9482 ANDY NW126 USDA-WA SAC SVN RKLD/MEC MAN 2602 UCD RKLD/MEC NW341 USDA-WA EXPERIMENT 3220, LARGE SEEDED YIELD TRIAL, MONTCALM - 1983 ACC. NO. C81001 T. HORT* MICRAN C81003 I82039 I82038 C81004 I82040 MANITOU C81009 SACRAMTO MONTCALM* K77003 I82028 CRAN-028 RED KLOUD* C81002 K77001 CHARL. I82037 I82030 MECOSTA S. BROWN ISABELLA I82027 I82029 RUDDY I81103 MEAN (28) LSD (.05) C.V. SEED* CLASS ENT. NO. YIEL YIEL D % CHK* D LB/A C C C C C C C C LRK C LRK DRK LRK LRK C LRK C LRK DRK C LRK LRK SB LRK LRK LRK LRK LRK 1 7 6 3 11 10 4 12 16 8 23 14 21 27 5 22 2 19 13 9 25 17 15 20 28 26 24 18 2371 2112 2066 2014 1999 1985 1985 1970 1879 1851 1840 1825 1822 1813 1780 1761 1719 1709 1674 1561 1463 1433 1401 1395 1375 1347 1278 948 empty table cell empty table cell empty table cell empty table cell empty table cell empty table cell 21.9 — 1728 537 112 100 98 95 95 94 94 93 107 88 104 100 103 103 84 100 81 97 92 74 83 81 —— 79 78 76 73 54 —— — 100 SEED WT.G. DAYS TO FL. 53.5 47.1 52.5 52.8 43.3 43.7 56.5 43.8 53.2 51.4 51.7 51.7 50.2 43.5 44.9 53.4 58.7 54.4 51.4 53.9 49.6 55.8 40.9 52.0 49.6 47.5 47.3 42.8 50.1 5.5 7.8 40 40 48 40 40 40 40 40 47 40 40 40 42 46 46 42 40 40 42 40 51 46 42 42 46 47 42 47 43 —— —— * % CHK - yield as percent of check is shown as percent of the check variety in each commercial class (C - Cranberry; LRK - Light Red Kidney; DRK - Dark Red Kidney; SB - Swedish Brown). PROCEDURE: Planted June 2, 1983, in 4 row plots — 18 foot long, 20 inch row width, 4 seeds/foot of row in a randomized complete block with 4 replications. A 14 foot section of the center two rows was pulled at maturity. LEGEND: FL. = flower MSU BEAN PROGRAM L1234 LINE TESTING MONTCALM 3221 KIDNEY, Anthracnose Program, Montcalm PLOT ENTRY ACC ORIG AND SOURCE PEDIGREE 28 18 22 07 02 33 24 26 41 48 22 01 CHAR RKLD/MEC 80K001-5-0-0-1 37 K83237 09 K82209 K83227 27 K83228 101 78K016-1-0-0-1 C49242/2-MONT C49242/4-MONT K83218 80K001-4-0-0-1 102 103 25 K83225 79K001-4-0-0-4 C49242/3-MONT K83208 80K001-2-0-0-2 C49242/4-MONT 104 08 49 K77003 105 70700 29 K83228 78K016-1-0-0-2 C49242/2-MONT 106 C49242/4-MONT 107 12 K83212 80K001-3-0-0-1 C49242/3-MONT 108 78K001-4-0-0-1 K83222 K83207 80K001-2-0-0-1C49242/4-MONT 109 78K001-1-0-0-2C49242/2-MONT K83202 110 C49242/4-MONT 111 K83233 80K001-5-0-0-2 K83224 C49242/3-MONT 79K001-4-0-0-3 112 113 05 K83205 C489242/4-MONT 80K001-1-0-0-1 C49242/2-MONT 114 79K001-4-0-0-5 K83226 11547 K77001 70684RKLD/MEC 116 19 K83219 80K001-4-0-0-2 C48242/4-MONT K83241 C48242/4-MONT 117 80K001-6-0-0-2 118 20 empty table cell empty table cell K83220 K77002 70688BKLD/MEC.ISA 119 C49242/4-MONT K83232 120 121 21K8322180K001-4-0-0-4C49242/4-MONT 79K001-5-0-0-1C49242/3-MONT 122 C49242/4-MONT 80K001-2-0-0-4 123 C49242/3-MONT 78K001-4-0-0-6 124 C49242/4-MONT 125 16 K83216 80K001-3-0-0-5 C49242/4-MONT 80K001-0-0-2 126 C49242/4- MONT 80K001-5-0-0-6 127 128 14 K83214 80K001-2-0-0-3C49242/4-MONT 129 15 K8321580K001-3-0-0-4 C49242/4-MONT C49242/4-MONT 130 131 44 K83244 79K001-5-0-0-1 C49242/2-MONT 132 42 K8324280K001-5-0-0-3 C49242/4-MONT C49242/4-MONT 80K001-6-0-0-1 40 K83240 133 C49242/4-MONT 80K001-2-0-0-6 134 11 K83211 80K001-2-0-0-2C49242/4-MONT 135 13 K83213 C49242/2-MONT 79K001-1-0-0-1 K83201 136 137 21 K83231 79K016-1-0-0-4 C49242/2-MONT 78K001-5-0-0-4 C49242/3-MONT 138 39 K83228 CHAR K00001 46 139 45 K74002 MONT MONT 140 C49242/2-MONT 78K016-2-0-0-4 141 43 K82243 C49242/4-MONT 80K001-5-0-0-5 K83235 142 25 80K01-4-0-0-3 C49242/4-MONT 20 K83220 143 144 28 22 K83223 145 03 K83203 146 K83204 04 147 K83217 17 148 10 K83210 149 K83228 78K001-5-0-0-3C49242/3-MONT 79K001-4-0-0-3 78K001-1-0-0-3 C49242/3-MONT C49242/4-MONT 78K001-2-0-0-3 C49242/4-MONT 90K001-2-0-0-6 C49242/4-MONT 80K001-2-0-0-5 80K001-5-0-0-3 C49242/3-MONT 06 26 K83206 K83236 24 K83234 EXPERIMENT 3221, PRELIMINARY DARK RED KIDNEY BEAN YIELD TRIAL, MONTCALM - 1983 ACC. NO. MONTCALM* K83243 K83207 K83233 N83231 K83227 K83222 K83210 K83230 K83204 K83215 K83236 K83244 CHARL. K83232 ISABELLA K83237 K83223 K83202 K83239 K83214 K83213 K83241 K83201 K83216 Mean (25) LSD (.05) C.V. ENT. NO. 45 43 07 33 31 27 22 10 30 04 15 36 44 46 32 48 37 23 02 39 14 13 41 01 16 empty table cell empty table cell empty table cell YIELD YIEL LB/A D % CHK* 1900 1825 1796 1790 1786 1706 1683 1680 1614 1598 1572 1509 1504 1502 1461 1381 1379 1372 1293 1238 1203 1197 1150 1140 1128 1502 528 25.2 100 96 94 94 94 90 89 88 85 84 83 79 79 79 77 73 73 72 68 65 63 63 61 60 59 80 —— — 100 SEED WT.G 51.8 52.6 51.5 53.9 47.9 50.4 53.6 50.0 45.1 47.9 51.8 51.3 49.6 51.6 46.1 51.3 45.5 50.3 48.5 45.7 50.0 52.0 48.9 51.0 44.8 49.8 3.8 5.3 DAYS TO FL. 47 46 46 47 47 46 46 49 46 49 47 45 46 47 45 43 47 50 47 47 49 48 45 46 46 48 — — PROCEDURE: Planted June 2, 1983 in 4 row plots — 18 feet long, 20 inch row width, 4 seed/foot of row, in a square lattice with 4 replications. A 14 foot section of the 2 center rows was pulled at maturity. LEGEND: FL. = flower MICHIGAN POTATO INDUSTRY COMMISSION 500 North Homer Street Lansing, Michigan 48912 Bulk Rate U.S. Postage PAID Permit No. 979 Lansing, Mich.