2003 COTTON RESEARCH REPORT Research Report No. 25 March 2004 Alabama Agricultural Experiment Station John Jensen, Interim Director Auburn University Auburn, Alabama Printed in cooperation with the Alabama Cooperative Extension System (Alabama A&M University and Auburn University) ACKNOWLEDGMENTS This publication is a joint contribution of Auburn University, the Alabama Agricultural Experiment Station, Alabama A&M University, and the USDA Agricultural Research Service. Research contained herein was partially funded through the Alabama Cotton Commission and private industry grants. All donations, including the Alabama Cotton Commission grants and private industry funding, are appreciated. CONFIDENTIAL REPORT Publication, display, or distribution of data contained herein should not be made without prior written approval. Mention of a trademark or product does not constitute a guarantee of the product by Auburn University and does not imply its approval to the exclusion of other products. Information contained herein is available to all persons regardless of race, color sex, or national origin. Issued in furtherance of Cooperative Extension work in agriculture and home economics, Acts of May 8 and June 30, 1914, and other related acts, in cooperation with the U.S. Department ofAgriculture. The Alabama Cooperative Extension System (Alabama A&M University and Auburn University) offers educational programs, materials, and equal opportunity employment to all people without regard to race, color national origin, religion, sex, age, veteran status, or disability. CONTENTS Editors, C ontributors ......................................... . .............. ......... .. .. .... .. .. .. .. ................... 5 VARIETY TRIALs Cherokee County Cotton Variety Trial .................... ......................................................... . ................................ ... .... ...... 7 2003 Elmore County Roundup Ready Cotton Variety Trial ...................... ............................................................... ............ ...................... 7 2003 Shelby County Roundup Ready Cotton Variety Trial ......................................................... .......................................... 8 No-Till Cotton Variety Evaluation at E.V. Smith Research Center ................................................................................................ 9 Evaluation of Cold Tolerant and Conventional Cotton Varieties and Planting Dates in South Alabama ...o........................ 10 Evaluation of Cold Tolerant and Conventional Cotton Varieties and Planting Dates in North Alabama ................................. 10 2003 Fusarium Wilt/Commercial Cotton Variety Test ...................................... ............................................... 11 Evaluation of Early Season Cotton Varieties for Response to Boll Rot Disease in Alabama ........................................ 12 Evaluation of Full Season Cotton Varieties for Response to Boll Rot Disease in Alabama ...................................................... 13 Cotton Variety Response to the Reniform Nematode in Escambia County, Alabama .............................................................. 14 Cotton Variety Response to the Reniform Nematode in Limestone County, Alabama ............ .................. 15 Cotton Variety Response to the Reniform Nematode in Lawrence County, Alabama ................................................... 16 Cotton Variety Response to the Reniform Nematode Following Corn in Lawrence County, Alabama .................................... 17 CROP PRODUCTION Comparison of Gylphosate-Tolerant and Non-Glyphosate-Tolerant Varieties in Full and Reduced Tillage Cotton Production Systems ......................................................................... 18 Effects of Variable Rate Nitrogen Applications on Conservation Tillage Cotton...... ...................................................... 19 Effect of Timing of Defoliation on Cotton Quality ..................... .................................. ..................................... ...................... 20 Subsurface Drip Irrigation Placement and Irrigation Water Requirements, Tennessee Valley Research and Extension Center .......................... ............... ...... ....................................... .. .......... ...... 21 Subsurface Drip Irrigation Tape Products and Fertigation, Tennessee Valley Research and Extension Center ........................... 22 Sprinkler Irrigation Water Requirements and Irrigation Scheduling, Tennessee Valley Research and Extension Center ................................................................. ...................... ..... 24 Impact of Non-host Crop Rotations and Winter Cover Crops on Cotton Production in Reniform Nematode-Infested Fields ....................................... ............ ......... .......... ....... .............................................. 25 Crop Rotation-An Effective Tool for Managing Reniform Nematodes in Cotton..................................................................... 26 Evaluation of Planting Date for Response to Boll Rot Disease in Alabama ....... ........................................ .............................. 27 Fertilization of Cotton on Black Belt Prairie Soils in Alabama .................................... .. 0 ....... ............ 28 Cullars Rotation (c. 1911): America's Oldest Continuous Cotton Fertility Experiment ............................................................... 29 INSECTICIDES Control of Cotton Aphids Infesting Cotton ................................................................. .. .................................... 31 M idseason M anagem ent of Tarnished Plant Bugs ........................................................................................................................ 31 Evaluation of WideStrike and Conventional Varieties for Heliothine Control ............................................................................. 32 NEMATICIDES Evaluation of Effectiveness of Temik 15G on Reniform Nematode Control in North Alabama .................................................... 33 Evaluation of Temik 15G Side-Dress Application for Reniform Nematode Management in Cotton in Central Alabama .............. 34 Comparing Three M ethods for Telone II Fum igation .................................................................................................................... 35 Evaluation of the Soil Fumigants Vapam and Telone II for Reniform Nematode Management in Cotton in North Alabama .......... 36 Evaluation of the Soil Fumigants Vapam and Telone II for Reniform Nematode Management in Cotton in South Alabama . 36 Effect of Gaucho, Cruiser Seed Treatments Versus Recommended Nematicides on Controlling Reniform N em atodes in Cotton .............................................................................. ................................... 37 Evaluation of Vydate C-LV for Reniform Nematode Management in Cotton in North Alabama .................................................. 39 CONTENTS, CONTINUED Evaluation of Equity for Root-Knot Nematode Management in Cotton in Central Alabama .................................................... 40 Evaluation of Biologicals for Reniform Nematode Management in Cotton in North Alabama .................................................. 41 Efficacy of Experimental Seed Treatment Nematicides for Management of the Root-Knot Nematode in Central Alabama ............ 42 Efficacy of an Experimental Seed Treatment Nematicide for Management of the Reniform Nematode in South Alabama ............. 43 Efficacy of an Experimental Seed Treatment Nematicide for Management of the Reniform Nematode in Central Alabama ........... 44 Efficacy of an Experimental Seed Treatment Nematicide for Management of the Reniform Nematode in North Alabama..........45 FUNGICIDES Evaluation of Selected Fungicides for Control of Cotton Boll Rot Disease in South Alabama .................................................. 46 Evaluation of Selected In-Furrow Fungicides for Management of Cotton Seedling Disease in North Alabama................. 47 Evaluation of Selected In-Furrow Fungicides for Management of Cotton Seedling Disease in Central Alabama................. 48 Evaluation of Selected Seed Treatment Fungicides for Management of Cotton Seedling Disease in North Alabama............. 49 Evaluation of Selected Seed Treatment Fungicides for Management of Cotton Seedling Disease in Central Alabama............51 MOLECULAR STUDIES Further Studies of a Gene Important for Cotton Fiber - Cellulose Synthase .......................................................................... 53 An Efficient Method for Isolating Large Numbers of Viable Reniform Nematodes, Rotylenchulus reniformis................. 54 A uthors' Index ....................................................................................................................................................................................... 55 2003 CO-rTON RESEARCH REPORT 5 EDITORS K.S. Lawrence Associate Professor Entomology and Plant Pathology Auburn University CONTRIBUTORS J.R. Akridge Superintendent Brewton Agricultural Research Unit R. Beauchamp County Agent, Elmore County Alabama Cooperative Extension System C.H. Burmester Extension Agronomist Tennessee Valley Research and Extension Center, Belle Mina, Alabama R. Colquitt County Agent, Shelby County Alabama Cooperative Extension System Larry M. Curtis Professor and Extension Specialist Biosystems Engineering, Auburn University D.R Delaney Extension Specialist IV,Agronomy and Soils Auburn University D. Delmer Rockefeller Foundation New York, New York D. Deng Department of Plant and Soil Science Alabama A&M University D. Derrick County Agent, Cherokee County Alabama Cooperative Extension System B. Durbin Superintendent Field Crops Unit, E.V. Smith Research Center Shorter, Alabama W.H. Faircloth Graduate Research Assistant Agronomy and Soils, Auburn University B.L. Freeman Extension Entomologist Entomology and Plant Pathology Auburn University W.S. Gazaway Professor and Extension Specialist, Emeritus Entomology and Plant Pathology Auburn University K. Glass Agricultural Program Associate Agronomy and Soils, Auburn University C.D. Monks Professor and Extension Specialist Agronomy and Soils Auburn University R.W. Goodman Associate Professor Agricultural Economics and Rural Sociology Auburn University D.H. Harkins Agricultural Program Assistant Tennessee Valley Research and Extension Center, Belle Mina, Alabama P. Hogan Section of Plant Biology University of California-Davis, Davis, Califomia G. Huluka Associate Professor Agronomy and Soils, Auburn University A. Jeffries Agronomy Department Iowa State University, Ames, Iowa J. Jenkins USDA/ARS/CSRL Mississippi State, Mississippi J. R. Jones Graduate Research Assistant Entomology and Plant Pathology Auburn University L. Kuykendall County Agent, Autauga County Alabama Cooperative Extension System G. W. Lawrence Entomology and Plant Pathology Mississippi State University K.S. Lawrence Associate Professor Entomology and Plant Pathology Auburn University R. McDaniel Superintendent Gulf Coast Research and Extension Center Fairhope, Alabama S. McLean Undergraduate Research Assistant Entomology and Plant Pathology Auburn University B.A. Meyer District Technical Services Manager Delta and Pine Land Company Hartselle, Alabama C.C. Mitchell Professor and Extension Agronomist Agronomy and Soils, Auburn University D.R Delaney Extension Specialist IV Agronomy and Soils Auburn University C.D. Monks Professor and Extension Specialist Agronomy and Soils, Auburn University D.P. Moore Superintendent Prattville Agricultural Research Unit B.E. Norris Superintendent Tennessee Valley Research and Extension Center, Belle Mina, Alabama S.H. Norwood County Agent, Colbert County Tennessee Valley Research and Extension Center, Belle Mina, Alabama M.G. Patterson Professor, Agronomy and Soils Auburn University M.D. Pegues Associate Superintendent Gulf Coast Research and Extension Center Fairhope, Alabama G. Sharma Department of Plant and Soil Science Alabama A&M University R.H. Smith Professor and Extension Specialist Entomology and Plant Pathology Auburn University K. Soliman Department of Plant and Soil Science Alabama A&M University Y. Tilahun Department of Plant and Soil Science Alabama A&M University S.R. Usery, Jr. Graduate Research Assistant Entomology and Plant Pathology Auburn University R.P. Yates Extension Agent, Dallas County Alabama Cooperative Extension System 0. Yurchenko Department of Plant and Soil Science Alabama A&M University Allan Zipf Department of Plant and Soil Science Alabama A&M University VARIETY TRIALS CHEROKEE COUNTY COTTON VARIETY TRIAL C.H. Burmester and D. Derrick Each season a cotton variety trial is conducted in Chero- kee County to supplement yield results from the Alabama Cot- ton Variety Trials. This large, cotton-growing area has unique soil types and farmers often use results of this test to evaluate new cotton varieties for northeast Alabama. In 2003, the trial was conducted on the farm of Randall and Nick McMichen on a Holston fine sandy loam soil. Cotton was planted into a winter cover crop of wheat on April 30 and consisted of eight rows of each variety planted the length of the field. The test was repli- cated twice across the field. A total of nine cotton YIELD AND QUALITY OF varieties were planted in 2003. Variety Seec All varieties were genetically modified and contained the Roundup Ready gene that DP 555 BG/RR 3 allows weed control applica- PM 1218 BG/RR 3 tions with Roundup Ultra until FM 960 BR 3 the 41 leaf stage. All variet- DP 444 BG/RR 3 ies were spindle picked, and ST 4892 BR 3 seed cotton was weighed in FM 989 BR 3 ST 5599 BR 3 a boll buggy. A seed cotton ST 5303 R3 sample from each variety was DP 449 BG/RR 3 ginned on a tabletop gin for 1Lint % determined on a small lint percentage and quality, normal turn-out at a cotton gin A very wet May flooded the first replication and was not used in the test results. Although the cotton maturity was de- layed by the cold, wet weather in May, late summer rainfall was good and produced an excellent crop. Insect pressure was low and only minimal control measures were required. Yields of all varieties were more than two bales per acre and quality was also excellent. DP 444 BG/RR did have a low micronaire value of 3.4 that was in the discount range. F COTTON VARIETIES IN THE CHEROKEE COUNTY TRIAL d cotton Lint yield Lint' yield Mic. 2 Length Unif. 3 Strength bs/ac % Ibs/ac units staple % g/tex 150 45.7 1450 4.2 35 82 28.6 358 42.4 1420 4.2 34 84 30.1 477 43.6 1520 3.8 36 84 33.0 632 45.2 1640 3.4 36 84 29.6 384 44.7 1510 4.4 37 83 31.5 398 42.1 1430 3.8 37 82 33.1 528 44.0 1550 4.4 37 83 31.5 361 42.7 1440 3.9 36 85 32.9 416 43.0 1470 4.2 36 84 31.4 cotton gin without cleaners. This percentage is usually higher than . 2 Mic.=micronaire. 3 Unif.=uniformity. 2003 ELMORE COUNTY ROUNDUP READY COTTON VARIETY TRIAL D.P. Delaney, C.D. Monks, L. Kuykendall, R. Beauchamp, and K. Glass One of the most critical decisions a cotton producer makes each year is which variety to plant. Many factors, such as yield potential and lint quality, are heavily influenced by seed selec- tion. Area cotton producers often ask for more site-specific information on the unique soils and situations on their farms. On-farm field trials are important to verify University research and to show how different varieties perform under typical man- agement practices in producers' fields. A field was selected on the Sanford Peeples farm near Holtville in Elmore County, Alabama. Fertilization and weed and insect control were maintained at optimum levels, accord- ing to Alabama Cooperative Extension System recommenda- tions. No significant worm damage was noted. The same pro- duction practices were carried out across all varieties, regard- less of technology or genetically engineered traits. Thirteen cotton varieties, all containing the Roundup Ready gene were planted on April 23, 2003, with three replica- tions of each variety in a complete block design. Each plot was eight field-length rows of a single variety. The center four rows of each plot were harvested on Sep- tember 25 with a spindle picker, and a weighing boll buggy was used to weigh each plot. One-pound grab samples were ginned on a mini-gin, and analyzed with HVI equipment at the USDA- AMS Birmingham Classing Office. ---- --- -r 8 ALABAMA AGRICULTURAL EXPERIMENT STATION Results showed that there m per acre of lint between the higi vars (see table). When USDA lc yield and quality values (not shown), there was a difference in total value of more than $140 per acre from the lowest to highest valued variety, mainly due to yield differ- ences. Area cotton producers can use these results to com- pare the performance of these varieties with the potential for significantly higher returns from their crop. Producers should not rely on any single source, however, to guide their choices, but should also use other information such as the multi-year data from the vas a difference of 258 pounds lest and lowest yielding culti- an values were applied to lint Alabama Agricultural Experiment Station official variety trials (http://www.alabamavarietytesting.com) and other public and private sources. ELMORE COUNTY ROUNDUP READY ON-FARM COTTON VARIETY TRIAL Lint yield Turnout Mic. Length Strength Uniformity Variety lbs/ac % units in o/tex % DP 555 BG/RR 952 44 4.5 1.14 28.8 83.3 ST 4892 BR 883 41 4.6 1.10 29.2 83.3 FM 991 BR 881 40 4.6 1.14 31.5 84.0 FM 989 RR 865 41 4.0 1.14 30.0 84.0 DP 5690 RR 862 40 4.4 1.11 30.3 82.0 ST 5599 BR 860 41 4.5 1.14 27.3 83.0 DP 451 B/RR 842 38 4.4 1.14 27.2 83.0 FM 960 BR 837 40 4.4 1.14 31.2 84.0 FM 991 RR 835 40 4.3 1.16 30.4 83.7 ST 5503 R 815 40 4.4 1.09 30.4 84.7 FM 989 BR 751 39 3.9 1.14 29.7 83.0 DP 655 B/RR 737 40 4.2 1.13 29.9 82.0 DP 449 BG/RR 694 40 4.2 1.10 29.6 83.0 LSD (P<0.10) 124 1 0.2 0.03 1.4 1.4 2003 SHELBY COUNTY ROUNDUP READY COTTON VARIETY TRIAL D.P. Delaney, C.D. Monks, R. Colquitt, and K. Glass One of the most critical decisions a cotton producer makes each year is which variety to plant. Many factors, such as yield potential and lint quality, are heavily influenced by seed selec- tion. Area cotton producers often ask for more site-specific information on the unique soils and situations on their farms. On-farm field trials are important to verify University research and to show how different varieties perform under typical man- agement practices in producers' fields. A field was selected on the Phillip Barber farm near Harpersville in Shelby County, Alabama. Fertilization and weed and insect control were maintained at optimum levels, accord- ing to Alabama Cooperative Experiment Station recommenda- tions. No significant worm damage was noted. The same pro- duction practices were carried out across all varieties, regard- less of technology or genetically engineered traits. Twelve cotton varieties, all containing the Roundup Ready gene were planted on April 21, 2003, with three replications of each variety in a complete block design. Each plot was four, field-length rows of a single variety. The center two rows of each plot were harvested on Oc- tober 3 with a spindle picker, and a weighing boll buggy was used to weigh each plot. One-pound grab samples were cleaned and ginned on a mini-gin, and analyzed with HVI equipment at the USDA-AMS Birmingham Classing Office. Results showed that there was a difference of 204 pounds per acre of lint between the highest and lowest yielding culti- vars (see table). There were also several significant differences in quality measurements between varieties. SHELBY COUNTY ROUNDUP READY ON-FARM COTTON VARIETY TRIAL Lint yield Mic. Length Strength Variety Ibs/ac units in g/tex DP 444 BG/RR 1181 3.7 1.12 28.5 ST 5599 BR 1179 4.2 1.10 29.7 ST 4892 BR 1171 4.3 1.11 29.6 ST 4793 R 1159 4.3 1.08 28.5 DP 449 BG/RR 1137 4.1 1.08 29.7 FM 989 RR 1135 3.6 1.11 31.8 FM 991 RR 1121 3.9 1.13 31.8 DP 555 BG/RR 1102 4.4 1.08 27.4 ST 5303 R 1088 4.2 1.08 30.4 SG 215 BR 1070 4.4 1.07 27.4 DP 436 RR 1025 4.3 1.12 27.7 DP 655 B/RR 977 4.1 1.11 31.9 LSD (P<0.05) 95 0.3 0.04 1.5 ~clr;n~;cr~ rrl;~ ~ka ~r\~a~r~;~l +-~r ALABAMAAGRICULTURAL ExPERIMENT STATION8 2003 COTTON RESEARCH REPORT 9 Area cotton producers can use these results to compare the performance of these varieties with the potential for signifi- cantly higher returns from their crop. Producers should not rely on any single source, however, to guide their choices, but should also use other information such as the multi-year data from the Alabama Agricultural Experiment Station Official Vari- ety Trials (http://www.alabamavarietytesting.com) and other public and private sources. NO-TILL COTTON VARIETIES AT E.V. SMITH RESEARCH CENTER D.P. Delaney, K. Glass, C.D. Monks, and B. Durbin An increasing acreage of cotton in Alabama is planted using conservation tillage of some kind. Growers have asked for information about performance of cotton varieties within the systems they use on their farms. The objective of this test was to compare the suitability of several commercially avail- able cotton varieties in a strip-till conservation tillage system. Twenty-two selected varieties were planted on a Cowarts loamy sand at the E.V. Smith Field Crops Unit on May 1 into a killed rye cover crop. After in-row subsoiling, four replications of two 40-inch rows, 20 feet long of each variety were planted with a no-till planter equipped with row cleaners and spoked closing wheels. Fertility and pesticide applications were made according to Alabama Cooperative Extension System recommen- dations. Plots were defoliated on September 15. Fifty-boll samples were taken from two replications, and ginned on a mini-gin for lint quality and turnout. Plots were picked on September 29. Yield and turnout results are presented in the table below. Lint yields were excellent and ranged from 1381 to 1793 pounds per acre. Lint turnout ranged from 38 to 45 percent. Producers can use these results to compare the relative performance of these varieties in various management systems. E.V. SMITH No-TILL COTTON VARIETY TRIAL, 2003 Lint yield Turnout Mic. Length Strength Uniformity Variety lbs/ac % units in q/tex % DP 493 1793 45 4.7 1.09 31 83 SG 747 1727 42 4.7 1.16 28 85 DP 444 BG/RR 1688 44 3.8 1.08 29 83 DP 555 BG/RR 1663 45 4.4 1.13 30 84 ST 4793 R 1595 42 5.0 1.08 28 84 DP 491 1581 43 4.3 1.17 32 82 FM 960 BR 1574 40 4.0 1.12 32 83 DP 5690 RR 1556 41 4.3 1.11 34 83 ST 5599 BR 1532 41 4.6 1.12 31 83 SG 215 BR 1528 41 4.4 1.09 28 83 DP NuCotn 33B 1522 39 4.4 1.13 30 83 FM989 RR 1519 42 4.1 1.11 33 83 ST 5303 R 1498 43 4.5 1.08 33 85 FM 966 1467 41 4.1 1.14 35 84 FM 991 RR 1459 41 4.3 1.14 33 84 PHY 410 RR 1449 41 4.6 1.12 30 85 DP 436 RR 1445 38 4.4 1.12 28 83 ST 4892 BR 1440 42 4.6 1.11 30 85 DP 451 B/RR 1416 39 4.6 1.10 29 83 DP Delta Pearl 1396 42 4.2 1.17 31 84 PHY 510 RR 1386 40 4.7 1.12 32 84 DP 449 BG/RR 1381 40 4.5 1.13 32 84 LSD (P<0.10) 192.8 1 0.4 0.04 2 2 CV 10.68 1 5.7 1.87 4 1 41__1 1_ _1 ~ L1 1 1 1 Im 1 r 2003 COTTON RESEARCH REPORT 9 EVALUATION OF COLD TOLERANT AND CONVENTIONAL COTTON VARIETIES AND PLANTING DAES IN SOUrH ALmAMA D.P. Delaney, C.D. Monks, M.D. Pegues, R. McDaniel, and K. Glass Seed for cotton cultivars currently grown in Alabama re- quire warm soils in order to germinate and develop properly. Soil temperatures must remain above 60OF for a period of sev- eral days; this normally occurs after early April in much of the state, but can be later. Cold fronts, rain, and heavy mulches used with conservation tillage can delay soil warming even further. Producers planting early run the risk of poor stands due to delayed germination and seedling disease, as well as stunting from chilling injury. If producers were able to plant earlier, soil moisture may be more favorable, and cotton would potentially have a longer growing season, would have peak flowering during the longest summer days, and might set bolls before soil moisture supplies are depleted by hot summer weather. In south Alabama, this may allow harvest before the peak of the hurricane season. Recently released cold-tolerant cotton varieties are claimed to germinate and grow well at tempera- tures well below the optimum for currently grown varieties. Two varieties each of cold-tolerant and conventional cot- ton cultivars were planted at each of three planting dates at the Gulf Coast Research and Extension Center, Fairhope, Alabama. One variety of each type was an early maturity and the other full season. Four replications of each variety, consisting of four rows, 25 feet long with a between row spacing of40 inches, were planted on April 1, April 14, and April 28, using conven- tional tillage. Initial land preparation and planting was delayed by persistent heavy rainfall. Fertility and pesticide applications were made according to Alabama Cooperative Extension System recommendations. Rainfall was plentiful through most of the season, and harvest conditions were generally good. Boll rot was heavy on the earliest planting date treatments due to persistent rainfall in August. Plots were defoliated and harvested with a spindle picker when each treatment was mature. One-pound grab samples were ginned on a mini-gin for lint quality and turnout, and lint ana- lyzed for quality by HVI at the USDA-AMS lab at Pelham, Alabama. Yield and turnout results are presented in the table. Lint yields were very good and ranged from 918 to 1811 pounds per acre. Lint turnout ranged from 40 to 43 percent (not shown). Although initial stands were affected by variety (not shown), good growing conditions allowed poor stands to com- pensate and yield relatively well. The latest planting date yielded the highest for all varieties, while much of the difference can be LINT YIELDS FROM COLD TOLERANT COTTON VARIETIES BY PLANTING DATES, GULF COAST RESEARCH AND EXTENSION CENTER, 2003 Cold Variety Maturity' tolerance' CT 110HQ Early Yes FM 958 Early NA CT 310HQ Full Yes DP 491 Full NA LSD (P<0.10) I As listed by seed company. 2 Planting dates. Lint yield (bs/ac) - 4/012 4/142 4/282 1399 1390 1639 1305 1264 1611 918 1249 1811 1045 1276 1717 290 attributed to severe boll rot and hardlock for the earlier planting dates. The early va- rieties tended to perform bet- ter than full season varieties at the earliest planting date, while the opposite was true at the latest planting date. Further testing will be needed to determine if these varieties have the potential to allow earlier planting for producers. EVALUATION OF COLD TOLERTAND CONVENTIONAL C ON VARIETIES AND PLANTING DArES I NoRm ALABiA D.P. Delaney, C.H. Burmester, C.D. Monks, B.E. Norris, and K. Glass Seed for cotton cultivars currently grown in Alabama re- quire warm soils in order to germinate and develop properly. Soil temperatures must remain above 60OF for a period of sev- eral days; this normally occurs after early April in much of the state, but can be later. Cold fronts, rain, and heavy mulches used with conservation tillage can delay soil warming even further. Producers planting early run the risk of poor stands due to delayed germination and seedling disease, as well as $I CUIOVI~6 IVIU L)VIIIU11IYIIY~VI~ VII~IVIIUI VVIa VWII VVIIYI ~~VIVI~~~ ~~Y ~L~LI~~~YIVII YI111I1) ~ ~~~~~Vr~) rL ~~WVUIIIW YIIV ~~j) ~VVU bl ~ 10 ALABAMAAGRICULTURAL ExPERIMENT STATION 2003Couo RESARCHREPOT 1 stunting from chilling injury. If producers were able to plant earlier, soil moisture may be more favorable, and cotton would potentially have a longer growing season, would have peak flowering during the longest summer days, and might set bolls before soil moisture supplies are depleted by hot summer weather. For northern areas, this may enable harvest before cold, wet fall weather, and in south Alabama, may allow harvest before the peak of the hurricane season. Recently released cold- tolerant cotton varieties are claimed to germinate and grow well at temperatures well below the optimum for currently grown varieties. Two varieties each of cold-tolerant and conventional cot- ton cultivars were planted at each of three planting dates at the Tennessee Valley Research and Extension Center, Belle Mina, Alabama. One variety of each type was an early maturity and the other full season. Four replications of each variety, consist- LINT YIELDS FROM COLD TOLERANT COTTON VARIETIE TENNESSEE VALLEY RESEARCH AND EXTENSION Cold Variety Maturity 1 tolerance 1 CT 110HQ Early Yes FM 958 Early NA CT 310HQ Full Yes DP 491 Full NA LSD (P<0.10) ' As listed by seed company. 2 Planting dates. Li 3/262 998 1171 823 919 ing of four rows, 25 feet long with a between row spacing of 40 inches, were planted on March 26, April 14, and April 23, using conventional tillage. Fertility and pesticide applications were made according to Alabama Cooperative Extension System recommendations. Rainfall was plentiful through most of the season, and harvest conditions were generally good. Plots were defoliated and harvested with a spindle picker when each treatment was mature. One-pound grab samples were ginned on a mini-gin for lint quality and turnout, and lint ana- lyzed for quality by HVI at the USDA-AMS lab at Pelham, Alabama. Yield and turnout results are presented in the table. Lint yields ranged from 779 to 1171 pounds per acre. Lint turnout ranged from 40 to 44 percent (not shown). Although initial stands were affected by variety (not shown), good growing con- ditions allowed poor stands S BY PLANTING DATES, to compensate and yield well. CENTER, 2003 FM 958, a conventional vari- nt yield (bs/ac) ety, generally performed as 4/142 4/232 well or better than the cold 929 817 tolerant listed varieties. Fur- 939 913 ther testing will be needed to 878 779 determine if these varieties 885 856 have the potential to allow 103 earlier planting for producers. 2003 FUSARIUM WILT/COMMERCIAL W.S. Gazaway and K. Glass Fifteen commercial cotton varieties commonly grown in Alabama were evaluated for Fusarium wilt resistance at the E.V. Smith Research Center, Plant Breeding Unit, Tallassee, Alabama. These varieties were grown on a Wickham fine, sandy loam. Varieties were planted in single 20-foot rows on 40-inch centers, separated at each end by 5-foot alleys. Four replica- tions of the test entries and the susceptible check, Rowden variety, were arranged in a randomized design. Ridomil at 8 pounds per acre was applied in the seed furrow at planting. Plots were planted on May 19, 2003. Initial plant counts were made on June 6. Wilted plants were counted and removed on July 15, July 29, August 15, and August 29, 2003. The re- maining live plants were counted and recorded on September 12, 2003. Four to six cotton plants per plot were also selected at random, carefully dug, and their roots rated for root-knot nema- tode severity using a gall rating index (5=80 percent roots galled; 1 =few or no galls on roots).Total percentage for wilted plants was determined and a mean wilting percentage was calculated for each variety (see table). A root-knot gall rating is also in- cluded in the table. COTTON VARIETY TEST COMMERCIAL VARIETIES RESPONSE TO FUSARIUM WILT AND TO ROOT-KNOT NEMATODES 93ii Variety Rowden FM 958 ST 4892 BR ST 4793R ST 580 SG 215 BR PM 1218 BG/RR DP 555 BG/RR PHY 410 RR PHY 355 DP 491 FM 989 BR FM 991 BR DP 458 BRR Fusarium wilt (%) 2002 2003 76 61 32 24 -2 18 20 - 18 - 12 10 17 9 15 9 - 8 11 - 12 7 10 6 10 6 8 5 Root-knot gall index' 2003 4.00 3.75 3.50 3.00 2.00 3.65 2.25 3.00 2.50 2.80 3.25 continued I II A A Il 2003 COTTON RESEARCH REPORT 11 12 ALABAMA AGRIcULTURAL EXPERIMENT STATION Fusarium wilt incidence in 2003 was not as great as in 2002 but was sufficiently high to separate relative susceptibil- ity of the cotton varieties in the test (see table). Most cotton varieties in the test (DP 451 BG/RR, DP 5690 RR, DP 458 BR/RR, Phytogen GA 161, Fiber Max 960 BR, Fiber Max 989 BR, and Stoneville 5599 BR) exhibited excellent to good resistance to Fusarium wilt. Most of these varieties had less root-knot nema- tode galls than the varieties more susceptible to wilt. Stoneville 4892 BR and Fiber Max 958 showed little resistance to wilt or to root-knot nematodes and should be avoided in fields where wilt or root-knot nematodes are a problem. CONTINUED, COMMERCIAL VARIETIES RESPONSE TO FUSARIUM WILT AND TO ROOT-KNOT NEMATODES Root-knot Variety Fusarium wilt (%) gall index' 2002 2003 2003 FM 960 BR 5 2.75 DP 444 BG/RR - 5 1.50 DP 5690 RR 7 4 2.60 ST 5599 BR - 3 1.75 DP 451 BG/RR - 3 1.75 PHY GA 161 7 - - SG 501 BR 7 - - 1 Root-knot nematode indices are determined as an average root gall rating from the roots of four plants per variety where: 1= few or no galls visible on the roots; 2=galls visible on 1 to 20 percent of the roots; 3=galls visible on 21 to 40 percent of the roots; 4=galls visible on 41 to 80 percent of the roots; 5=galls visible on over 80 percent of the roots. 2 Cotton variety not in test that year. EVALUATION OF EARLY SEASON COTTON VARIETIES FOR RESPONSE TO BOLL ROT DISEASE IN ALABAMA J.R. Jones, K.S. Lawrence, S.R. Usery Jr., K. Glass, and M.D. Pegues A cotton variety trial was planted on May 5 at the Gulf Coast Research and Extension Center, Fairhope, Alabama. The soil type was a Malbis fine sandy loam. Plots consisted of two rows, 25 feet long, with a between-row spacing of 38 inches. Plots were arranged in a randomized complete-block design with four replications. A 10-foot alley separated blocks. Cotton boll rot was evaluated by recording the number of healthy bolls and diseased bolls from a 0.001 acre sec- tion within each plot. All EVALUATION OF EP plots were maintained TO BOL Although weather conditions were favorable, the inci- dence of boll rot was relatively low for the early season variet- ies in 2003. The disease index for boll rot ranged from 10 per- cent for Beltwide Cotton Genetics BCG 295 to a low rating of 1 percent for Deltapine DP 449 BG/RR. Seed cotton yields varied by 1315 pounds per acre between the Deltapine DP NuCotn 33B and Sure-Grow SG 747 varieties. ARLY SEASON COTTON VARIETIES FOR RESPONSE L ROT DISEASE IN ALABAMA, 2003 throughout the season with standard herbicide, insecti- cide, and fertility production practices as recommended by the Alabama Cooperative Extension System. Plots were harvested on Septem- ber 30. Data were statistically analyzed using PROC ANOVA, and means were compared with Fisher's pro- tected least significant dif- ference test. Variety BCG 28R BCG 295 DP 436 RR DP 444 BG/RR DP 449 BG/RR DP 451 B/RR DP NuCotn 33B FM 958 FM 958B FM 960 BR FM 832B FM 966 Healthy bolls' no. 65.5 66.0 78.0 88.8 78.0 71.0 95.5 71.5 79.5 81.3 78.3 62.3 Diseased bolls' no. 4.8 6.5 7.3 5.0 0.8 3.0 4.3 3.3 4.5 3.3 2.3 2.5 Disease index 2 7.0ab 10.3a 9.8ab 5.7ab 1.2b 4.3ab 4.5ab 4.2ab 5.2ab 3.8ab 2.9ab 4.7ab Seed cotton yield lbs/ac 2284.8bc 2150.4bc 2697.6abc 2659.2abc 3043.2abc 3292.8a 3408.0a 3196.8ab 3292.8a 2860.8abc 2553.6abc 2803.2abc continued -- --- -- . ~__ __1_~__'__1 __~__~_1_1_~~__1 11__ 12 ALABAMAAGRICULTURAL ExPERIMENT STATION 2003 CoTFoN RESEARCH REPORT 13 CONTINUED, EVALUATION OF EARLY SEASON COTTON VARIETIES FOR RESPONSE TO BOLL ROT DISEASE IN ALABAMA, 2003 Variety Healthy bolls' Diseased bolls' Disease Seed cotton yield no. no. index 2 lbs/ac FM 989 BR 96.8 4.0 4.3ab 2659.2abc PM 1199 RR 77.3 6.5 6.8ab 2544.0abc PM 1218 BG/RR 88.0 2.8 3.0ab 3043.2abc PHY 410 RR 71.3 4.8 7.lab 2880.0abc ST 4793R 75.3 5.0 6.7ab 2534.4abc ST 4892 BR 67.5 3.0 4.2ab 2870.4abc STX 4646 BR 88.5 7.5 8.7ab 2966.4abc SG 105 80.8 5.0 6.2ab 3312.0a SG 215 BR 62.3 2.3 3.9ab 2793.6abc SG 747 76.3 3.3 ? 4.lab 2092.8c SG 521R 83.5 6.3 8.8ab 2870.4abc LSD (P<.005) 37.5 6.7 8.7 955.3 1 Number of bolls per 6.5 feet of row. 2 Disease index = (no. of diseased bolls /total no. of healthy bolls) x100. Means within columns followed by different letters are significantly different according to Fisher's LSD (P < 0.05). EVALUATION OF FULL SEASON COTTON VARIETIES FOR RESPONSE TO BOLL ROT DISEASE IN ALABAMA J.R. Jones, K.S. Lawrence, S.R. Usery Jr., K. Glass, and M.D. Pegues A cotton variety trial was planted on May 5 at the Gulf Coast Research and Extension Center, Fairhope, Alabama.The soil type was a Malbis fine sandy loam. Plots consisted of two rows, 25 feet long, with a between-row spacing of 38 inches. Plots were arranged in a randomized complete block design with four replications. A 10-foot al- ley separated blocks. Cotton boll rot was evaluated by recording the number of healthy bolls and diseased bolls from a 0.001acre section within each plot. Plots were maintained throughout the season with standard herbicide, insecticide, and fertility production prac- tices as recommended by the Alabama Cooperative Extension System. Plots were harvested on October 16. Data were statis- tically analyzed using PROC ANOVA, and means were com- EVALUATION OF FULL SEASON COTTON VARIETIES FOR RESPONSE TO BOLL ROT DISEASE IN ALABAMA, 2003 Variety Healthy bolls' Diseased bolls' Disease index 2 Seed cotton yield no. no. Ibs/ac BCG 24R 101.5a 6.5ab 6.5a 3360.0c-g Delta Pearl 79.3ab 4.5ab 5.3a 3801.6a-d DP 448B 76.8ab 4.8ab 6.0a 4089.6ab DP 449 BG/RR 89.5ab 5.8ab 6.9a 4185.6a DP 458 BRR 104.3a 5.0ab 4.7a 3801.6a-d DP 491 78.0ab 4.8ab 6.0a 3782.4a-e DP 493 85.0ab 7.0ab 8.3a 3379.2c-g DP 5415 RR 84.0ab 5.5ab 6.8a 3648.0a-f DP 555 BG/RR 93.0ab 4.0ab 4.2a 3897.6abc DP 5690 RR 92.0ab 7.3ab 8.9a 3763.2a-e DP NuCotn 33B 92.5ab 7.0ab 7.5a 3859.2a-d FM 991R 72.8ab 5.3ab 7.6a 3859.2a-d continued pared with Fisher's pro- tected least significant dif- ference test. Disease index for boll rot ranged from 10 percent for Stoneville ST 4892 BR to a low rating of 3 percent for Fiber Max FM 991 BR. Seed cotton yields varied by 1133 pounds per acre for Delta Pine DP 449 BG/RR and Stoneville STX 5242 BR, re- spectively. Numerically, Fi- ber Max FM 991 BR had the lowest incidence of boll rot. Ah LI lr AA r~ A A A A A I 2003 COTTON RESEARCH REPORT 13 14 ALABAMA AGRIcULTURAL EXPERIMENT STATION CONTINUED, EVALUATION OF FULL SEASON COTTON VARIETIES FOR RESPONSE TO BOLL ROT DISEASE IN ALABAMA, 2003 Variety Healthy bolls' Diseased bolls' Disease index 2 Seed cotton yield no. no. Ibs/ac FM 989 81.5ab 6.3ab 7.8a 3148.8fg FM 989 RR 84.3ab 7.5ab 8.7a 3379.2c-g FM 989 BR 86.5ab 6.3ab 8.Oa 3398.4c-g FM 991 BR 85.3ab 2.3b 2.7a 4166.4a PHY 510 RR 90.0ab 3.Oab 3.Oa 3609.6b-f ST 4892 BR 85.8ab 8.8a 10.1a 3820.8a-d ST 5599 BR 89.8ab 5.5ab 6.2a 3417.6c-g ST 5303R 84.3ab 4.0ab 4.8a 3321.6d-g STX 4646 BR 87.5ab 7.8ab 9.5a 3148.8fg STX 5242 BR 72.5ab 4.0ab 5.7a 3052.8g SG 747 67.0b 5.5ab 8.4a 3244.8efg LSD (P<0.05) 34.3 6.3 8.1 553.8 'Number of diseased bolls per 6.5 feet of row. 2 Disease index = (no. of diseased bolls /total no. healthy bolls) x 100. Means within columns followed by different letters are significantly different according to Fisher's LSD (P < 0.05). COTTON VARIETY RESPONSE TO THE RENIFORM NEMATODE IN ESCAMBIA COUNTY, ALABAMA S.R. Usery Jr., K.S. Lawrence, J.R. Jones, J.R. Akridge, K. Glass, and G.W. Lawrence Thirty two cotton varieties were examined with and with- out Telone II for their response to the reniform nematode (Rotylenchulus reniformis) near Huxford, Alabama. The test was planted on May 1, 2003 in a producer's field naturally in- fested with the reniform nema- tode and monocultured in cotton. Telone II at 3 gallons per acre was applied a month before planting with a ripper/ bedder injection device. Plots consisted of one row, 25 feet long with a 36-inch row spac- ing. All plots were maintained throughout the season with standard herbicide, insecti- cide, and fertility practices as recommended by the Alabama Cooperative Extension System. Population densities of reniform nematode were de- termined at planting and at harvest. Soil cores, 1 inch in diameter and 8 inches deep, were collected from each one- row plot in a systematic sam- pling pattern. Nematodes were extracted using gravity sieving and sucrose centrifuga- tion technique from 150cc sub-samples. Data were statistically analyzed using PROC ANOVA, and means were compared with Fisher's protected LSD test. CorroN VARIETY RESPONSE TO RENIFORM NEMATODE IN ESCAMBIA COUNTY, ALABAMA, 2003 Variety Reniform/150cc Reniform/150cc Lint yield -at planting' - - ----at harvest-- ----- bs/ac Telone no Telone Telone no Telone Telone no Telone BCG 28R 2343 1802 1468 1057 726 549 Delta Pearl 2343 1802 1699 640 964 788 DP 436 RR 2343 1802 1236 794 689 336 DP 444 BG/RR 2343 1802 1545 960 601 583 DP 448B 2343 1802 695 3528 980 475 DP 449 BG/RR 2343 1802 1545 1646 836 689 DP 451 B/RR 2343 1802 927 1181 746 385 DP 458 BRR 2343 1802 1545 849 951 517 DP 491 2343 1802 1545 1176 932 398 DP 493 2343 1802 1004 1863 924 713 DP 5415 RR 2343 1802 927 1501 883 563 DP 555 BG/RR 2343 1802 1081 1773 1299 1072 DP 5690 RR 2343 1802 1545 1655 1025 694 DP NuGotn 33B 2343 1802 1004 2171 978 572 FM 991 RR 2343 1802 1030 694 1084 941 FM 958B 2343 1802 1313 1343 915 515 continued C11/ncn~ab o E=i 14 ALABAMAAGRICULTURAL 'ExPERIMENT STATION 2003 CorroN RESEARCH REPORT 15 CONTINUED, COTTON VARIETY RESPONSE TO RENIFORMNEMATODE IN ESCAMBIA COUNTY, ALABAMA,2003 Variety Reniform/l50cc Reniform/l5Occ Lint yield -at planting'- -at harvest- lbs/ac Telone no Telone Telone no Telone Telone no Telone FM 960 BR 2343 1802 2240 1929 866 589 FM 966 2343 1802 1622 1370 720 494 FM 989 2343 1802 1545 1169 772 504 FM 989 BR 2343 1802 1467 2333 857 470 FM 991 BR 2343 1802 952 1214 1145 1052 PM 1218 BG/RR 2343 1802 541 1260 730 588 PHY 410 RR 2343 1802 1236 1090 798 362 PHY 510 RR 2343 1802 1313 1430 920 582 ST 4793R 2343 1802 1545 1361 840 906 ST 4892 BR 2343 1802 1467 1089 804 595 ST 5303R 2343 1802 772 2327 912 482 ST 5599 BR 2343 1802 798 1490 706 523 ST 5242 BR 2343 1802 1159 965 745 498 SG 215 B/R 2343 1802 1184 1626 849 756 SG 521 RR 2343 1802 412 815 816 641 SG 747 2343 1802 695 1836 835 531 LSD (P<0,05) -1856-1901- 66 6- 'Average reniform populations before planting. Reniform nematode dis- ease pressure was moderate in 2003. Reniform nematode populations at harvest varied 2099 per 150cc of soil for DP 5690 RR with Telone 11 and ST 5242 BR with Telone , respec- tively. Lint cotton yields var- ied 695 pounds per acre be- tween DP 444 BG/RR and DP 555 BGIRR, respectively. Cot- ton plots treated with Telone out yielded the control plots (see table). The exceptions were the varieties FM 991 BR, SG 215 BR, ST 4793 RR, and DP 444 BG/RR, which pro- duced higher seed cotton yields in the non-Telone treated plots than in the Telone-treated plots. COTTON VARIETY RESPONSE TO THE IN LIMEsTONE COUNTY, AIABxmv1 S.R. Usery Jr., K.S. Lawrence, J.R. Jones, C.H. Burmester, K. Glass, and Twelve transgenic cotton varieties were examined with and without Telone II for their response to the reniform nema- COTTON VARIETY RESPONSE To RENIFORM IN LIMESTONE COUNTY, Variety DP 5415 RR ST 4892 BR DP 451 B/RR DP 436 RR DPL 444 BG/RR DP 449 BG/RR PM 1218 BG/RR SG 215 B/R PM 1199 RR ST 4793R ST 5599 BR FM 989 BR LSD (P<0,05) Telone No Telone LSD (P<0,05) Reniform at planting' 57.9bc 112.7ab 80.5a-c 25.7c 74.Oa-c 96.6a-c 80.Sa-c 86.9a-c 64.4a-c 38.6bc 86.9a-c 138.4a 77.9 74.Oa 83.2a 31,8 Reniform at harvest 463.5ab 598.8ab 293.Ob 434.8ab 1100.9a 347.8b 833.9ab 428.3ab 361.6b 251.3b 730.Bab 273.8b 675.3 471.7a 548.Oa 275,7 ALABAMA, 2 Reniform rej ductive imd 8.0 5.3 3.6 16.9 14.9 3.6 10.4 4.9 5.6 6.5 8.4 2.0 6.4 6.6 RENIFORM NEMATODE G.W. Lawrence tode (Rotylenchulus reniformis) in north Alabama. The test was planted on May 1, 2003 in a producer's field naturally in- fested with the reniform nema- tode and monocultured in cot- iNEMATODE ton. The soil is a Decatur silt 1903 loam. Telone 11 at 3 gallons per pro- Seed cotton yield acre was applied one month lex lbs/ac before planting with a ripper! 4245.Scd bedder injection device. Plots 4034.7de consisted of two rows, 25 feet 4794.3ab long with a 40-inch row spac- 4444.8a-d ing. All plots were maintained 4818.Bab with standard production prac- 4516.6a-c tices recommended by the Ala- 4247. lcd bama Cooperative Extension 4475.8a-c Sse n omnyue 3739. le Sse n omnyue 4423.5b-d in the area. 4880.9a Population densities of 4547.7abc reniform nematode were deter- 439.1mined at planting, peak bloom, 4595a and at harvest. Soil cores, 4265b l inch in diameter and 8 inches 179 _ 'Average reniform populations before planting. ~ *~h~ ~rr ~~ACI I Ar~ OI\A WHOMMENNUMM 2003 C017ON RESEARCH REPORT 15 16 ALABAMA AGRICULTURAL EXPERIMENT STATION deep, were collected from the rows in each two-row plot in a systematic sampling pattern. Nematodes were extracted using gravity sieving and sucrose centrifugation technique. Plots were harvested on October 14. Data were statistically analyzed using PROC ANOVA, and means were compared with Fisher's protected LSD test. Reniform nematode disease pressure was low in 2003. Reniform nematode numbers increased from planting to har- vest in 100 percent of the plots as indicated by reproductive factors (Rfs). Rfs varied from 16.9 for DP 436 RR to 2.0 for FM 989 BR. No variety exhibited a Rf value below 1, indicating that they were all susceptible to the reniform nematode. Cotton seed yield varied 1141.8 pounds per acre between ST 5599 BR and PM 1199 RR, respectively. DP451 B/RR, DP 444 BG/RR, and ST 5599 BR produced higher seed cotton yields (see table) than DP 5415 RR, ST 4892 BR, PM 1218 BG/RR, and PM 1199 RR. Cotton plots treated with Telone II out yielded the control plots. COTTON VARIETY RESPONSE TO THE RENIFORM NEMATODE IN LAWRENCE COUNTY, ALABAMA S.R. Usery Jr., K.S. Lawrence, J.R. Jones, C.H. Burmester, and B.A. Meyer Transgenic cotton varieties were examined with and with- out Temik 15G for their response to the reniform nematode (Rotylenchulus reniformis) in a monocultured cotton field in Lawrence County, Alabama. The test was planted on April 19 in a producer's field naturally infested with the reniform nema- tode. The soil is a Decatur silt loam. Temik 15G (at a rate of 7 pounds per acre) was applied at planting in the seed furrow with chemical granular applicators attached to the planter. Cruiser-treated seeds were used to control thrips in all non- Temik plots. Plots consisted of one row, 200 feet long with a 30- inch row spacing. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility prac- tices as recommended by the Alabama Cooperative Extension System. Plots were not irrigated. Population densities of reniform nematode were deter- mined at planting, peak bloom, and at harvest. Each row was sampled individually in a systematic sampling pattern. Nema- todes were extracted using gravity sieving and sucrose cen- trifugation technique. Plots were harvested on October 6. Data were statistically analyzed using PROC ANOVA, and means were compared with Fisher's protected LSD test. Reniform nematode disease pressure was extremely low throughout the growing season (see table). Reniform nema- tode numbers increased from planting to harvest in 100 percent of the plots as indicated by reproductive factors (Rfs). Rfs varied from 4.8 for SG 215 B/R without Temik to 1.2 for DPLXO3L300 BR without Temik. No variety exhibited an Rf value below 1, indicating that they were all susceptible to the reniform nematode. Cotton seed yield varied 1126 pounds per acre between DP 424 BGIIR plus Temik and DP 555 BR without Temik. Cotton plots with Temik out yielded the control plots. COTTON VARIETY RESPONSE TO RENIFORM NEMATODE IN LAWRENCE COUNTY ALABAMA, 2003 Variety Reniform Reniform Reniform Seed cotton yield -at planting - -at peak bloom- --reproductive factor- - lbs/ac Ternik no Temik Temik no Ternik Temik no Temik Ternik no Temik ST 4892 BR 57.9 77.2 83.6b 199.5b 1.4 2.6 2692e-h 2523hi FM 960 BR 57.9 77.2 100.Ob 173.8b 1.7 2.3 3100bc 2980cd DP 555 BG/RR 57.9 77.2 199.5b 173.8b 3.4 2.3 2526hi 2394i DP 468BIIR 57.9 77.2 180.1b 128.7b 3.1 1.7 2711e-h 2646g-i DP 449 BG/RR 57.9 77.2 218.8b 167.3b 3.8 2.2 2851c-g 2938c-e DP 424 BIIR 57.9 77.2 90.1b 122.3b 1.6 1.6 3520a 3308ab PM 1218 BG/RR 57.9 77.2 122.3b 148.0b 2.1 1.9 2838d-g 2808d-g DPLXO3L300BR 57.9 77.2 173.8b 94.3b 3.0 1.2 3309ab 3099bc SG 215 B/R 57.9 77.2 154.5b 373.3a 2.7 4.8 2695e-h 2683f-h DP 444 BG/RR 57.9 77.2 218.8b 173.8b 3.8 2.3 2907c-f 2877c-g LSD (P<0.05) 153.0 -- - 254.3 'Average reniform populations before planting; number per 150cc. ALA13AMAAGRICULTURAL ExPERIMENT STATION HY~+d~+d~ I ~I ~ ~d~+ 16 COTTON VARIETY RESPONSE TO THE RENIFORM NEMATODE FOLLOWING CORN IN LAWRENCE COUNTY, ALABAMA S.R. Usery Jr., K.S. Lawrence, J.R. Jones, C.H. Burmester, and B.A. Meyer Transgenic cotton varieties were examined with and with- out Temik 15G for their response to the reniform nematode (Rotylenchulus reniformis) following corn in north Alabama. The test was planted on April 19 in a producer's field naturally infested with the reniform nematode after a year of corn pro- duction. The soil is a Decatur silt loam. Temik 15G (at a rate of 7 pounds per acre) was applied at planting in the seed furrow with chemical granular applicators attached to the planter. Cruiser-treated seeds were used to control thrips in the non- Temik plots. Plots consisted of one row, 200 feet long with a 30- inch row spacing. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility prac- tices as recommended by the Alabama Cooperative Extension System. Plots were not irrigated. Population densities of reniform nematode were deter- mined at planting, peak bloom, and at harvest. Each row was sampled individually in a systematic sampling pattern. Nema- todes were extracted using gravity sieving and sucrose cen- trifugation technique. Plots were harvested on October 6. Data were statistically analyzed using PROC ANOVA, and means were compared with Fisher's protected LSD test. Reniform nematode disease pressure was extremely low throughout the growing season (see table). Reproductive fac- tors varied from a low of 0.4 in DP436 RR, PM 1199 RR, and PM 1218 BG/RR Cruiser-treated plots to a high of 3.3 in the SG 215 B/R Temik. Cotton seed yield varied 924 pounds per acre be- tween SG 501 BR plus Temik and DP 5415 RR with Cruiser. Temik 15G application had no effect on seed cotton yield. The absence of a treatment effect is likely the result of the low reniform populations in this field at planting following the pre- vious year in corn production. COTTON VARIETY RESPONSE TO RENIFORM NEMATODE FOLLOWING CORN IN LAWRENCE COUNTY ALABAMA, 2003 Variety Reniform Reniform Reniform Seed cotton yield -at planting 1 - -at peak bloom- -reproductive factor- .Ibs/ac Temik no Temik Temik no Temik Temik no Temik Temik no Temik DP 5415 RR 25.75 51.50 19.3c 45.0a-c 0.7 0.9 2630ef 2432f ST 4793 R 25.75 51.50 12.8c 32.1bc 0.5 0.6 2994b-d 2840c-e DP 436 RR 25.75 51.50 77.2ab 19.3c 3.0 0.4 2599ef 2782c-f SG 521 R 25.75 51.50 12.8c 25.7c 0.5 0.5 3216ab 3236ab PM 1199 RR 25.75 51.50 32.1bc 19.3c 1.3 0.4 2749d-f 2550ef ST 4892 BR 25.75 51.50 32.1bc 25.7c 1.3 0.5 3131a-c 3340ab SG 501 BR 25.75 51.50 32.1bc 25.7c 1.3 0.5 3356a 3245ab SG 215 B/R 25.75 51.50 83.6a 38.6a-c 3.3 0.8 2617ef 2701d-f PM 1218 BG/RR 25.75 51.50 19.3c 19.3c 0.7 0.4 2527ef 2454f DP 451 B/RR 25.75 51.50 12.8c 45.0a-c 0.5 0.9 2542ef 2459f LSD (P