ACKNOWLEDGEMENTS 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, Cotton Incorporated, and private industry support. 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 of Agriculture. 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, Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 VARIETY TRIALS Response of Cotton Varieties to Rotylenchulus reniformis in a Greenhouse, 2004 . . . . . . . . . . . . . . . . . . . . 5 Response of Selected Transgenic Cotton Varieties to Rotylenchulus reniformis in North Alabama, 2004 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Cherokee County Cotton Variety Trial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Screening Commercial Cotton Varieties Against Fusarium Wilt, 2004 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Screening Cotton Germplasm for Heat and Osmotic Stress Tolerance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Breeding Cotton for Yield and Quality in Alabama . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Evaluation of Cold Tolerant and Conventional Cotton Varieties and Planting Dates at the Tennessee Valley Research and Extension Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Evaluation of Cold-Tolerant and Conventional Cotton Varieties and Planting Dates at the Gulf Coast Research and Extension Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Evaluation of Cold Tolerant and Conventional Cotton Varieties and Planting Dates at the Prattville Agricultural Research Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Evaluation of Cold Tolerant and Conventional Cotton Varieties and Planting Dates at the Wiregrass Research and Extension Center. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 On-farm Cotton Variety Evaluations, 2004 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 CROP PRODUCTION Rotating Cotton With Non-host Crops to Control Reniform Nematodes . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Subsurface Drip Irrigation (SDI) Tape Products and Fertigation, Tennessee Valley Research and Extension Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Surface Drip Irrigation (SDI) Placement and Irrigation Water Requirements, Tennessee Valley Research and Extension Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Evaluation of Pressure Compensating Subsurface Drip Irrigation (SDI) on Rolling Terrain for Cotton Production . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Sprinkler Irrigation Water Requirements and Irrigation Scheduling, Tennessee Valley Research and Extension Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Fifty Years of Soil Testing for Cotton in Alabama . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 2004 Yields: The Old Rotation (circa 1896) and Cullars Rotations (circa 1911) . . . . . . . . . . . . . . . . . . . . . 29 INSECTICIDES Evaluation of Granular Insecticides, Seed Treatments, and Foliar Over-sprays for Thrips Control on Cotton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Thrips Control on Seedling Cotton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 HERBICIDES AND DEFOLIANTS Comparison of Glyphosate-tolerant and Conventional Weed Management Systems in Full- and Reduced-Tilled Cotton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Effect of Timing of Defoliation on Cotton Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 NEMATICIDES Evaluation of Temik 15G and New Experimental Compounds for Root-knot Nematode Management in Cotton in Central Alabama, 2004 . . . . . . . . . . . . . . . . . . . . . 38 Evaluation of Recommended and Experimental Compounds for Reniform Nematode Management in Cotton in North Alabama, 2004 . . . . . . . . . . . . . . . . . . . . . . . 39 Evaluation of Telone II, Vapam HL, and Temik 15G for Reniform Nematode Management in Cotton in North Alabama, 2004 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Evaluation of Seed Treatment Nematicides for Reniform Nematode Management in Cotton in North Alabama, 2004 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 FUNGICIDES Evaluation of Selected Fungicide Seed Treatments for Management of Cotton Seedling Disease in Central Alabama, 2004. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Evaluation of Selected Fungicides for Management of Cotton Seedling Disease in the Tennessee Valley Region of Alabama, 2004. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Evaluation of Selected Fungicide Seed Treatments for Management of Cotton Seedling Disease in the Tennessee Valley Region of Alabama, 2004 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Evaluation of Selected In-furrow Fungicides for Management of Cotton Seedling Disease in Central Alabama, 2004. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 2004 COTTON RESEARCH REPORT 3 EDITORS K.S. Lawrence Associate Professor Entomology and Plant Pathology Auburn University C.D. Monks Professor and Extension Specialist Agronomy and Soils Auburn University D.P. Delaney Extension Specialist IV Agronomy and Soils Auburn University CONTRIBUTORS J.R. Akridge Superintendent Brewton Agricultural Research Unit K.S. Balkcom Affiliate Assistant Professor, Agronomy and Soils USDA-National Soil Dynamics Laboratory Auburn University C.H. Burmester Extension Agronomist Tennessee Valley Research and Extension Center L.M. Curtis Emeritus Professor and Extension Specialist Biosystems Engineering Auburn University D.P. Delaney Extension Specialist IV Agronomy and Soils Auburn University W.H. Faircloth Graduate Research Assistant Agronomy and Soils Auburn University B.L. Freeman Extension Entomologist Entomology and Plant Pathology Auburn University J.P. Fulton Assistant Professor Biosystems Engineering Auburn University B. Gamble Associate Superintendent Wiregrass Research and Extension Center W.S. Gazaway Professor and Extension Specialist, Emeritus Entomology and Plant Pathology Auburn University K. Glass Agricultural Program Associate Agronomy and Soils Auburn University D.H. Harkins Agricultural Program Assistant Tennessee Valley Research and Extension Center K.B. Holland G.W. Lawrence Entomology and Plant Pathology Mississippi State University K.S. Lawrence Associate Professor Entomology and Plant Pathology Auburn University R.D. Locy Professor Biological Sciences Auburn University R. McDaniel Superintendent Gulf Coast Research and Extension Center C.C. Mitchell Professor and Extension Agronomist 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 M.G. Patterson Professor Agronomy and Soils Auburn University M.D. Pegues Associate Superintendent Gulf Coast Research and Extension Center R. Raper Affiliate Professor USDA-National Soil Dynamics Laboratory Auburn University J.N. Shaw Associate Professor Agronomy and Soils Auburn University R.H. Smith Professor and Extension Specialist Entomology and Plant Pathology Auburn University S.R. Usery, Jr. Graduate Research Assistant Entomology and Plant Pathology Auburn University D.B. Weaver Professor Agronomy and Soils Auburn University 2004 COTTON RESEARCH REPORT 5 VARIETY TRIALS RESPONSE OF COTTON VARIETIES TO RENIFORM NEMATODE IN A GREENHOUSE, 2004 S.R. Usery, Jr., and K.S. Lawrence Fifty-two cotton varieties were screened in a greenhouse for resistance to the reniform nematode (Rotylenchulus reniformis). Each variety was planted into a 150-cc container in sterile soil. Prior to emergence, each container was inoculated with 1,000 vermiform R. reniformis. Varieties were arranged in a randomized complete block design with five replications per test. Two separate tests at different planting dates were performed. Sixty days after planting, varieties were harvested. The roots were carefully removed from each pot and R. reniformis eggs were extracted from the roots with a 10-percent NaOCl solution. The soil was extracted using the Baermann funnel technique. Rotylenchulus reniformis were enumerated using a stereo microscope. Plant growth was also measured to determine early season vigor in a test planted as previously stated. Twenty days after emergence, plants were evaluated. Shoot length, root and shoot fresh weights, and root and shoot dry weights were recorded. Data were statistically analyzed using PROC GLM, and means compared with Fisher's protected least significant difference test (P<0.05). All varieties tested supported reproduction of R. reniformis. Total vermiform R. reniformis plus egg populations varied from a high of 59,354 for Deltapine 488 BR to a low of 4,092 for Sure Grow 105. There was no significant correlation between R. reniformis or egg populations when compared to shoot length, shoot weight and root weight. Response of Cotton Varieties to Reniform Nematode in a Greenhouse, 2004 VARIETY Stoneville 4892 BR FiberMax 958 LL Deltapine 491 Deltapine 449 BR Deltapine 488 BR Deltapine 434 RR Stoneville 5303 RR DeltaPearl Stoneville 4646 B2R Stoneville 5242 BR FiberMax 991 BR FiberMax 991 B2R FiberMax 989 BR FiberMax 966 LL FiberMax 960 BR FiberMax 991 RR Deltapine 451 BR Beltwide Cotton Genetics 28 R Deltapine 493 Deltapine 494 RR Deltapine 458 BR Deltapine 5415 RR RENIFORM 150 CM3 SOIL 10,066 b-e 20,487 a 18834 a 15,280 ab 19,699 a 4,574 e-k 5,622 c-k 4929 d-k 5,524 c-j 4,319 f-k 10,626 bc 6,798 c-i 4,604 e-k 3,811 f-k 3,438 f-k 5,122 c-k 3,925 f-k 4,738 e-k 4,612 e-k 5,817 c-k 6,034 c-k 7,409 c-h RENIFORM EGGS 150 CM3 SOIL 19,856 e-n 26,291 d-j 28145 d-i 20,111 e-n 39,655 a-d 20,832 e-n 21,012 e-m 18,849 f-o 47,535 a-c 30,952 d-h 27,066 d-i 29,123 d-i 30,720 d-h 26,858 d-i 27,424 d-i 18,669 f-o 28,093 d-i 20,291 e-n 27,115 d-i 22,017 e-m 28,712 d-i 30,214 d-h SHOOT LENGTH (CM) 12.80 d-o 11.54 k-o 11.56 l-o 11.68 j-o 11.50 k-o 14.26 a-h 14.10 a-i 11.52 k-o 13.56 a-k 13.50 a-l 15.56 a 15.44 ab 13.90 a-j 13.68 a-k 12.87 d-o 12.61 f-o 13.45 a-l 12.00 i-o 10.90 n-o 12.77 d-o 12.50 g-o 13.18 c-m SHOOT DRY WEIGHT ROOT DRY WEIGHT (G ) 0.222 f-r 0.221 f-r 0.187 n-r 0.217 g-r 0.161 r 0.216 g-r 0.236 b-p .0229 e-q 0,237 b-o 0.290 a-e 0.286 a-f 0.296 a-d 0.281 a-g 0.228 e-q 0.219 g-r 0.228 e-q 0.246 b-n 0.199 k-r 0.172 o-r 0.227 e-r 0.250 b-n 0.190 m-r (G) 0.078 i-n 0.078 i-n 0.100 e-n 0.157 a-f 0.060 l-n 0.092 g-n 0.113 d-m 0.064 l-n 0.094 g-n 0.212 ab 0.150 b-h 0.167 a-d 0.184 a-c 0.108 d-n 0.089 h-n 0.079 i-n 0.114 d-l 0.048 n 0.088 h-n 0.219 a 0.072 j-n 0.051 mn 6 ALABAMA AGRICULTURAL EXPERIMENT STATION Response of Cotton Varieties to Reniform Nematode in a Greenhouse, 2004 (continued) VARIETY RENIFORM 150 CM3 SOIL RENIFORM EGGS 150 CM3 SOIL 26,085 d-j 32,316 c-g 28,300 d-i 16,429 h-p 46,543 a-c 23,828 e-l 10,480 k-p 10,477 k-p 14,160 i-p 17,974 g-p 8,285 l-p 34,631 b-e 48,050 ab 34,067 b-f 34,029 b-f 51,325 a 25,161 d-k 17,582 g-p 2,446 p 9,154 l-p 4,252 op 5,264 n-p 6,682 m-p 11,225 j-p 34,067 b-f 16,029 h-p 17,266 g-p 25879 d-k 26,729 d-j 26,072 d-j 15,582 SHOOT LENGTH (CM) 13.79 a-j 11.07 m-o 13.21 b-m 14.33 a-g 12.06 h-o 11.82 j-o 13.50 a-l 15.32 a-c 13.79 a-j 13.08 c-n 15.32 a-c 12.83 d-o 14.82 a-f 13.07 d-n 13.56 a-k 14.69 a-g 13.60 a-k 10.89 n-o 12.55 g-o 14.95 a-d 14.88 a-e 13.81 a-j 13.59 a-k 12.70 d-o 13.63 a-k 13.70 a-k 14.19 a-i 12.72 d-o 10.80 o 13.81 a-j 2.240 SHOOT DRY WEIGHT ROOT DRY WEIGHT (G) 0.227 e-r 0.191 m-r 0.231 c-p 0.297 a-c 0.194 l-r 0.231 c-p 0.239 b-n 0.259 a-l 0.297 a-c 0.198 k-r 0.302 ab 0.230 d-p 0.319 a 0.226 e-r 0.258 a-l 0.291 a-e 0.292 a-e 0.201 j-r 0.256 a-m 0.274 a-h 0.270 a-i 0.206 i-r 0.212 h-r 0.261 a-k 0.247 b-n 0.252 b-n 0.267 a-j 0.163 qr 0.170 p-r 0.298 ab 0.0669 (G) 0.120 d-l 0.137 c-i 0.092 g-n 0.149 c-h 0.134 c-j 0.090 h-n 0.129 c-k 0.118 d-l 0.129 c-k 0.101 e-n 0.107 d-n 0.127 c-k 0.138 c-i 0.130 c-k 0.089 h-n 0.131 c-k 0.120 d-l 0.078 i-n 0.140 c-i 0.106 d-n 0.161 a-e 0.079 i-n 0.100 e-n 0.132 c-j 0.153 b-g 0.142 c-h 0.098 f-n 0.051 mn 0.069 k-n 0.128 c-k 0.0628 Deltapine 444 BG/RR Deltapine 436 RR Deltapine 424 B2R Paymaster 1218 BG/RR Fiber Max 960 B2R Deltapine 555 BG/RR Sure-Grow 747 Sure-Grow 215 BR Stoneville 5599 BR Sure-Grow 521 RR Stoneville 4793 RR Phytogen 410 RR DPLX 02X39BR DPLX 00W12 DPLX 02T57R Beltwide Cotton Genetics 50 R STX 6636 BR Deltapine 432 RR Sure-Grow 105 Deltapine 5690 RR DPLX 03Q301DR DPLX 01W93BR Fiber Max 989 RR STX 6848 RR Fiber Max 960 RR STX 3636 B2R STX 4575 BR Beltwide Cotton Genetics 24 R STX 5454 B2R STX 4686 RR LSD (P<0.05) 10,344 b-d 6,273 c-j 8,490 c-f 7,802 c-g 2,457 g-k 2,001 h-k 2,441 g-k 3,546 f-k 2,078 h-k 1,840 i-k 3,361 f-k 5,670 c-k 4,015 f-k 3,623 f-k 4,427 f-k 3,909 f-k 4,581 e-k 2,673 g-k 1,646 i-k 2,124 h-k 520 k 595 k 833 jk 1,151 jk 2,094 h-k 1,715 i-k 2,472 g-k 1,978 h-k 2,804 g-k 2,943 g-k 5,528 2004 COTTON RESEARCH REPORT 7 RESPONSE OF SELECTED TRANSGENIC COTTON VARIETIES TO ROTYLENCHULUS RENIFORMIS IN NORTH ALABAMA, 2004 S.R. Usery Jr., K.S. Lawrence, C.H. Burmester, and G.W. Lawrence Twelve transgenic cotton varieties were examined with and without Telone II for their response to the reniform nematode (Rotylenchulus reniformis) in north Alabama. The test was planted on April 29, 2004, in a producer's field naturally infested with the reniform nematode and monocultured in cotton. The soil was a Decatur silt loam. Telone II at three gallons per acre was applied one month before planting with a modified John Deere ripper/bedder injection device. A CO2charged system was used to propel the fumigants through flow regulators mounted on stainless steel delivery tubes attached to the trailing edge of forwardswept chisels. Telone II was injected 18 inches deep. Rows were immediately hipped with disk hillers to seal the fumigant. Plots consisted of two rows, 25 feet long with 40-inch row spacing. All plots were maintained with standard production practices recommended by the Alabama Cooperative Extension System and commonly used in the area. Population densities of reniform nematode were determined at planting, peak bloom, and at harvest. Soil cores, one inch in diameter and eight inches 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 October 27, 2004. Data were statistically analyzed using PROC GLM, and means were compared with Fisher's protected least significant difference test (P<0.05). Reniform nematode disease pressure was moderate in 2004. The application of Telone II increased seed cotton yields and percent lint turnout, while reducing final reniform nematode populations (P<0.05). Seed cotton yields increased 7 percent and lint turnout increased 1 percent in plots treated with Telone II. The application of Telone II reduced final reniform nematode populations 29 percent. Cotton seed yields in plots treated with Telone varied 1,374 pounds per acre between Stoneville 5599 BR and Deltapine 5415 RR, respectively. Seed cotton yields in untreated plots varied 974 pounds per acre between Fiber Max 960 BR and Stoneville 4793 RR, respectively. Telone II had the least amount of impact on Fiber Max 989 RR and Fiber Max 960 BR with only a 2.1-percent yield decrease in nontreated plots. Application of Telone II had the greatest impact on Stoneville 4793 RR with a 16.3-percent yield decrease in the nontreated plots. Response of Selected Transgenic Cotton Varieties to Rotylenchulus reniformis in North Alabama, 2004 VARIETY Deltapine 444 BG/RR Deltapine 449 BG/RR Deltapine 451 BG/RR Deltapine 5415 RR FiberMax 960 BR FiberMax 989 RR FiberMax 991 BR Paymaster 1218 BG/RR Stoneville 4793 RR Stoneville 4892 BR Stoneville 5599 BR Stoneville X 4686 RR LSD (P<0.05) % LINT TURNOUT % LINT TURNOUT TELONE II CONTROL 0.4175 ab 0.4050 bc 0.3750 d 0.4200 a 0.4200 a 0.4150 a-c 0.4025 c 0.4175 ab 0.4175 ab 0.4175 ab 0.4125 a-c 0.4175 ab 0.0131 0.4175 a 0.4025 bc 0.3800 d 0.4025 bc 0.4050 a-c 0.4100 a-c 0.4000 c 0.4075 a-c 0.4075 a-c 0.4150 ab 0.4100 a-c 0.4175 a 0.0131 SEED COTTON TELONE II 4,790.0 ab 4,105.5 cd 4759.5 a-c 3,847.0 d 4,756.8 a-c 4,460.5 b-d 4,244.5 b-d 4,350.8 b-d 4,261.5 b-d 4,397.8 b-d 5,221.8 a 4,610.8 a-c 667.19 SEED COTTON CONTROL 4,218.5 a-c 3,789.0 cd 4,428.5 ab 3,714.3 cd 4,542.8 a 4,368.5 ab 4,153.8 a-c 3,978.5 b-d 3,568.5 d 4,035.0 a-d 4,436.3 ab 4,411.0 ab 512.63 PER RENIFORM 150 CC TELONE II PER RENIFORM 150 CC CONTROL 1,410.0 ab 2,027.8 ab 1,777.0 ab 1,448.0 ab 1,506.0 ab 579.0 ab 811.0 ab 1,236.0 ab 1,081.0 ab 2,395.0 ab 444.0 a 1,255.0 b 1,854.7 1,931.0 a 1,776.0 a 2,105.0 a 2,143.0 a 2,414.0 a 1,911.0 a 1,429.0 a 1,217.0 a 2,259.0 a 2,395.0 a 1,699.0 a 1,467.0 a 1,534 8 ALABAMA AGRICULTURAL EXPERIMENT STATION CHEROKEE COUNTY COTTON VARIETY TRIAL C.H. Burmester and D. Derrick Each season a cotton variety trial is conducted in Cherokee County to supplement yield results from the Alabama cotton 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 2004, 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 wheat cover crop on April 23 and consisted of eight rows of each variety planted the length of the field. The variety DP 444 BG/RR was used as a check variety across the field. A total of nine cotton varieties were planted in 2004. All varieties were genetically modified and contained the Roundup Ready gene that allows weed control applications with Roundup Ultra until the fourthleaf stage. All varieties were spindle picked, and seed cotton was weighed in a boll buggy. A seed cotton sample from each variety was ginned on a tabletop gin for lint percentage. Insect pressure was low much of the season, with plant bugs being the dominant pest problem. Yields were very high in this test location. However, hurricane Ivan's wind and rain damaged the area in midSeptember. The varieties DP 444 BG/RR and ST 5242 BR sustained the most damage since these early-maturing varieties had the most open cotton. Phytogen 410R yield was not reported due to flooded spots in the field. Cotton Variety Test Results in Cherokee County VARIETY DP 555 BG/RR FM 960 BR ST 5599 BR DP 432R DP 434R BCG 28R DP 444 BG/RR ST 5242 BR Phytogen 410 R SEED COTTON LB/A LINT* % 44.0 42.5 40.4 41.8 43.1 40.1 41.6 41.2 39.8 LINT LB/A 3,406 3,423 3,502 3,284 3,075 3,297 3,142 3,156 ** 1,499 1,455 1,415 1,373 1,325 1,322 1,307 1,300 ** *Lint percentage determined on a small gin without cleaners. This percentage is usually higher than normal turnout. **A low spot in the field reduced yields of this variety and, thus, it was not included in the report. SCREENING COMMERCIAL COTTON VARIETIES AGAINST FUSARIUM WILT, 2004 W.S. Gazaway and K. Glass Fusarium wilt has been successfully controlled through the use of resistant varieties during the past 50 years. Some of the newer genetically engineered cotton varieties do not have good Fusarium wilt resistance. Consequently, wilt has become a serious problem in wilt-infested fields where these varieties have been grown. In 2003, several of these susceptible varieties were severely damaged as a result of Fusarium wilt. To avoid this problem in the future, we established a Fusarium wilt nursery to identify susceptible commercial varieties. The commercial varieties and their susceptibility to Fusarium wilt is published annually in the Alabama Cotton IPM recommendations and in the Cotton Variety Report. Fifteen of the most commonly grown cotton varieties were screened for wilt. Rowden, an extremely susceptible cotton variety, was used as the Fusarium wilt susceptible control. Plots were 20 feet long and 16 rows wide. The test contained five replicates. Plants were first evaluated for wilt soon after they reached the first true-leaf stage. Thereafter, plots were evaluated for wilt on a weekly basis throughout the growing season until just before harvest. Plants were counted and removed as soon as they exhibited symptoms of Fusarium wilt. At the end of the season, four plants from each plot were dug carefully and their roots were evaluated for rootknot galls using a galling index of 1 to 5.1 The relative susceptibility of commercial cotton varieties in the test is shown in the following table. Cotton varieties were rated using the root-knot gall index (1-5). Root-knot incidence of all cotton varieties including Rowden averaged between 2 and 3. In previous years (2002 and 2003), distinct differences in the incidence of root-knot galling could be discerned among the more susceptible Fusarium wilt cotton varieties and those varieties that were more resistant. 2004 COTTON RESEARCH REPORT Commercial Varieties Response to Fusarium Wilt and to Root-knot Nematodes, 2004 VARIETY Rowden FiberMax 98LL Stoneville 4646BR Stoneville 4892 BR FiberMax 958 Stoneville 4793 RR Stoneville 580 Fiber Max 989BR Paymaster 1218BG/RR SureGrow 215BG/RR FiberMax 960BR Phytogen 410RR Fiber Max 991BR Deltapine 555BG/RR Stoneville 5303RR Deltapine 449BG/RR Deltapine 444BG/RR Deltapine 491 Deltapine 488BG/RR Deltapine 5690RR Stoneville 5599BR Deltapine 451BG/RR Deltapine 458BG/RR ** ** ** 32 20 18 10 17 12 ** ** 10 ** ** ** ** ** ** 7 ** ** ** PERCENT FUSARIUM 2002 2003 76 ** ** 18 11 ** ** 3 3 3 3 3 1 0 ** ** 3 2 ** 2 1 0 3 WILT 9 2004 61 59 17 10 ** ** ** 15 ** ** 10 8 ** 7 5 5 3 3 3 ** 2 1 ** SCREENING COTTON GERMPLASM FOR HEAT AND OSMOTIC STRESS TOLERANCE D.B. Weaver and R.D. Locy **Cotton variety not in test that year. All Deltapine varieties in this test showed good to excellent resistance to Fusarium wilt in 2004. Stoneville 5599BR and Stoneville 5303RR also showed excellent to good resistance to the wilt fungus, whereas, Stoneville 4646BR and Stoneville 4892 BR appeared to be more susceptible (see table). Most FiberMax varieties appeared to be extremely susceptible to wilt. 1Root-knot nematode root indices are reported as an average root gall rating from roots of four plants per variety, where 1= few or no galls visible on roots; 2 = galls visible on 1 to 20 percent of the roots; 3 = galls visible on 20 to 40 percent of the roots; 4 = galls visible on 41 to 80 percent of the roots; and 5 = galls visible on over 80 percent of the roots. Developing adapted cotton germplasm with tolerance to heat and drought is an important objective of many cotton breeding programs. To be successful, there must exist a genetic source of heat and drought tolerance, and there must be a way of evaluating cotton lines for heat and drought tolerance that is relatively rapid and accurate. Our objectives were to develop a rapid method of heat tolerance evaluation and to apply this method in evaluating the entire G. hirsutum USDA germplasm collection for heat tolerance. We developed a procedure based on chlorophyll fluorescence, on the assumption that fluorescence (light emission) is a function of chlorophyll activity. We subjected seedlings of 1,380 different cotton types collected from various countries around the world to increasingly higher temperatures (up to 55°C, or 130°F) for up to one hour. Chlorophyll fluorescence was measured after exposure to each temperature. This value was compared to a base value of chlorophyll fluorescence under normal (30° C, or 86° F) conditions. The higher the ratio of heat-stressed chlorophyll fluorescence to normal fluorescence, the more activity the chlorophyll retains following heat treatment. Theoretically, lines with a high ratio would have more heat tolerance. In our initial round of screening, we identified 53 cotton lines (referred to as the elite set) that had fluorescence ratios that were at least two standard deviations higher than the average for the entire group. We also identified 73 additional accessions with fluorescence ratios that were very close to the elite set. We intend to continue to evaluate these lines under more precise conditions and begin crossing them with adapted cotton germplasm to study inheritance of heat tolerance and begin the process of transferring heat tolerance into adapted lines. 10 ALABAMA AGRICULTURAL EXPERIMENT STATION BREEDING COTTON FOR YIELD AND QUALITY IN ALABAMA D.B. Weaver For U.S. cotton producers to remain competitive and profitable, it is necessary to continue to search for and develop superior varieties for production. Superior lint yield and lint quality are among the traits a new variety must possess. In order to continue to make progress in these areas, three conditions must be met: (1) There must be sufficient genetic variation for traits of interest; (2) There must be an efficient method of selecting for those traits in the generations immediately following the cross; and (3) the traits should be heritable. Recent years have seen little improvement in cotton yields and fiber quality. Several reasons have been suggested for this, among them the possibility that genetic variation may be declining due to a narrow genetic base for upland cotton, and the possibility that too much effort has been directed recently toward the commercialization of technology-added cotton. A cotton breeding project was initiated at Auburn University in 2001 by making initial crosses among several well-adapted cultivars and germplasms. Our overall objectives were twofold: (1) to develop cotton germplasm and cultivars with improved lint yield and fiber quality traits adapted to Alabama and (2) to study the genetic variability and heritability of various quantitative traits in cotton, including the effects of various inbreeding methods on the variance and heritability of those same traits. Traits of particular interest are lint yield, lint percentage, fiber weight per seed, earliness, and fiber quality traits, particularly those related to length, length uniformity, short fiber content, and fiber maturity. During 2002, six F2 populations, along with their parents and F1 progeny, were grown in the field and more than 1,500 individual plants were sampled and fiber analyzed by AFIS (Advance Fiber Information Systems). During 2003, we grew approximately 1,300 progeny rows from these individual F2 plants (F2:3 lines) (pedigree method) and also grew single plant progenies from each F2 plant (single-seed descent method). Three plants were sampled from each of the F2:3 lines (pedigree) lines for determination of fiber traits by AFIS. Based on analysis of traits on a single-plant basis in the F2 and F3 generations, it appears that adequate genetic variation exists for many traits, but often they are population- and/or generation-specific. Fiber length, for example, was heritable in some populations, but not others. Short fiber content was not heritable among F2 plants but was a heritable trait among F3 plants. Lint weight/seed was highly heritable among F2 plants but was not a heritable trait among F3 plants. Based on fiber quality traits, we have selected the best 300 lines and will begin yield-testing of these lines at Tallassee and Prattville during 2005. This will be our first chance to measure the yield potential of these lines and estimate statistical parameters related to yield. We will continue to study these populations, and determine heritability and genetic variation among these lines as they are moved from testing on a single-plant basis to being observed on a replicated plot basis. Only by growing replicated plots can we make determination of the degree of genetic variation on the most important trait of all-lint yield. 2004 COTTON RESEARCH REPORT 11 EVALUATION OF COLD-TOLERANT AND CONVENTIONAL COTTON VARIETIES AND PLANTING DATES AT THE TENNESSEE VALLEY RESEARCH AND EXTENSION CENTER D.P. Delaney, C.D. Monks, C.H. Burmester, B.E. Norris, and K. Glass Seed for cotton cultivars currently grown in Alabama require warm soils in order to germinate and develop properly. Soil temperatures must remain above 60° F for several days, which normally occurs after early April in much of the state. Cold fronts, rain, and heavy mulches used with conservation tillage can delay this even further. Producers who plant early in the season run the risk of poor stands, 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, peak flowering would more likely occur during the longest summer days, and cotton may set bolls before soil moisture supplies are depleted by hot weather. For northern areas, this may enable harvest before cold, wet fall weather. Recently released "cold-tolerant" cotton varieties are claimed to germinate and grow well at temperatures well below the optimum for currently grown commercial varieties. Two varieties each of "cold-tolerant" and "conventional" cotton cultivars were planted at each of three planting dates at the Tennessee Valley Research and Extension Center (TVREC) in Belle Mina. One variety of each type was an early maturity and the other full season. Four replications of four 40-inch rows by 25foot long plots of each variety were planted on April 6, 16, and 28, 2004, 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. Cotton was defoliated, 100 boll samples were handpicked, and plots harvested with a spindle picker when each treatment was mature. Seed cotton samples were ginned on a mini-gin for lint quality and turnout, and lint was analyzed 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 1,409 to 1,770 pounds per acre. Lint turnout ranged from 40 to 44 percent. Stands were lower for the first planting date. The only significant difference in varieties was between CT 212 HQ, a claimed "cold-tolerant" cultivar, and FM 958. Although initial stands from the first planting were less, good growing conditions allowed poor stands to compensate and yield well. Factorial analysis indicated that there was no significant effect of planting date on yield, lint turnout, or quality measurements. Cultivars, however, did yield significantly differently across planting dates, and were different for most lint quality aspects (data not shown). Further testing will be needed to determine if these varieties have the potential to allow earlier planting for producers. Lint Yields from Cold-Tolerant Varieties by Planting Dates, TVREC, 2004 PLANTING Date Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 3 Planting Date 3 Planting Date 3 Planting Date 3 LSD (P=.10) CULTIVAR CT 110 HQ CT 212 HQ FM 958 DP 491 CT 110 HQ CT 212 HQ FM 958 DP 491 CT 110 HQ CT 212 HQ FM 958 DP 491 20 STAND plants/50 ft 126 134 104 117 156 165 153 155 157 159 145 172 134 LINT YIELD b/A 1,448 1,739 1,614 1,656 1,409 1,751 1,653 1,770 1,532 1,744 1,557 1,762 1 TURNOUT % 40 42 43 44 40 42 44 44 41 43 43 44 12 ALABAMA AGRICULTURAL EXPERIMENT STATION EVALUATION OF COLD-TOLERANT AND CONVENTIONAL COTTON VARIETIES AND PLANTING DATES AT THE GULF COAST RESEARCH AND EXTENSION CENTER D.P Delaney, C.D. Monks, M.D. Pegues, R. McDaniel, and K. Glass Seed for cotton cultivars currently grown in Alabama requires warm soils in order to germinate and develop properly. Soil temperatures must remain above 60° F for several days, which normally occurs after early April in much of the state. Producers who plant early in the season run the risk of poor stands 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. Peak flowering would more likely occur during the longest summer days, and cotton may set bolls before soil moisture is depleted by hot 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 temperatures well below the optimum for currently grown varieties. Two varieties each of "cold-tolerant" and "conventional" cotton cultivars were planted at each of three planting dates at the Gulf Coast Research and Extension Center (GCREC) in Fairhope, Alabama. One variety of each type was an early maturity and the other full season. Four replications of four 40-inch rows by 25-foot long plots of each variety were planted on April 2, 16, and 29, 2004, using conventional tillage. Initial land preparation and planting were delayed by persistent heavy rainfall. Fertility and pesticide applications were made according to Alabama Cooperative Extension System recommendations. Rainfall was plentiful to excessive through most of the season. Boll rot ranged from 7 to 14 percent in midSeptember (Table 1) due to persistent rainfall during boll maturity. Due to the approach of Hurricane Ivan, a one-meter (about 3.3 feet) row section of each plot in the first replication was handpicked and weighed. These samples were ginned on a mini-gin for lint quality and turnout, and lint was analyzed for quality by HVI at the USDA-AMS lab at Pelham, Alabama (Table 2). Ivan destroyed the test, and no further data were available. Plant stands improved for all varieties from the first to the third planting date. Stands also improved from the tenth day after planting (10 DAP) to 21 DAP for the first two planting dates, but not for the third, when conditions were warmer. CT 110HQ, a "cold-tolerant" cultivar, had a higher stand count at 10 DAP than DP 491 for the first two planting dates, but not for the third date. Table 1. Stand and Boll Data, Cold Tolerant Varieties by Planting Dates, GCREC, 2004 PLANTS 10 DAP* PLANTS/60 FT 65 52 44 43 61 46 22 30 136 107 114 140 20 PLANTS 21 DAP PLANTS/60 FT 72 51 64 55 72 50 56 53 136 104 119 138 20 BOLLS % OPEN 9/14/2004 87 75 68 72 77 65 65 69 77 79 71 66 15 BOLLS % DISEASED 9/14/2004 8 9 7 14 9 13 7 11 8 8 8 7 7 PLANTING DATE Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 3 Planting Date 3 Planting Date 3 Planting Date 3 LSD (P=.10) *DAP=Days after planting VARIETY CT 110 HQ CT 212 HQ FM 958 DP 491 CT 110 HQ CT 212 HQ FM 958 DP 491 CT 110 HQ CT 212 HQ FM 958 DP 491 2004 COTTON RESEARCH REPORT Table 2. Lint Yield and Quality, Cold-Tolerant Varieties by Planting Dates, GCREC, 2004 PLANTING DATE Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 3 Planting Date 3 Planting Date 3 Planting Date 3 VARIETY CT 212 HQ FM 958 DP 491 CT 110 HQ CT 212 HQ FM 958 DP 491 CT 110 HQ CT 212 HQ FM 958 DP 491 LINT lb/a 989 1,114 706 690 1,089 1004 1221 858 1,030 830 573 TURNOUT % 39 40 40 38 40 40 39 40 39 39 38 MIC* units 3.9 5.1 4.8 3.4 4.1 4.6 4.7 4.0 3.8 4.5 4.1 LENGTH inches 1.08 1.14 1.17 1.06 1.11 1.17 1.21 1.14 1.14 1.20 1.23 STRENGTH g/tex* 29.0 33.6 29.6 26.1 30.6 31.6 31.8 31.4 29.9 32.1 31.0 UNIF.* % 82 81 82 79 83 82 84 84 84 84 83 13 *G/tex=Grams per tex; Mic=micronaire; Unif. =uniformity. Yield and turnout results from the first replication are presented in Table 2. Lint yields are subject to some uncertainty, due to a variable stand and only one-meter row of harvest, but ranged from 573 to 1,l04 pounds per acre of open cotton before the hurricane. Lint turnout ranged from 38 to 40 percent. Plentiful mid-season rainfall allowed cotton in plots with poor stands to compensate. Further testing will be needed with machine harvesting to determine if these varieties have the potential to allow earlier planting and economical yields for producers. EVALUATION OF COLD-TOLERANT AND CONVENTIONAL COTTON VARIETIES AND PLANTING DATES AT THE PRATTVILLE AGRICULTURAL RESEARCH UNIT D. P. Delaney, C.D. Monks, C.H. Burmester, D.P. Moore, and K. Glass Seed for cotton cultivars currently grown in Alabama require warm soils in order to germinate and develop properly. Soil temperatures must remain above 60° F for several days, which normally occurs after early April in much of the state. Cold fronts, rain, and heavy mulches used with conservation tillage can delay this even further. Producers who plant early in the season run the risk of poor stands, 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. Peak flowering would more likely occur during the longest summer days, and cotton may set bolls before soil moisture supplies are depleted by hot weather. For northern areas, this may enable harvest before cold, wet fall weather. 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" cotton cultivars were planted on each of three planting dates at the Prattville Agricultural Research Unit (PARU) in Prattville, Alabama. One of the varieties was an early maturity and the other full season. Four replications of four 36-inch rows by 28-foot long plots of each variety were planted on April 2 and 19 and May 5, 2004, using conventional tillage. Fertility and pesticide applications were made according to Alabama Cooperative Extension System recommendations. Rainfall was plentiful through most of the season. Hurricane Ivan caused signifi- 14 cant damage to early maturing varieties in midSeptember, and harvest was further delayed by wet weather. Plots were defoliated and then harvested with a spindle picker on October 18. One-pound grab samples were ginned on a mini-gin for lint quality and turnout, and lint was analyzed for quality by HVI at the USDAAMS lab at Pelham, Alabama. Yield and turnout results are presented in the table below. Harvested lint yields ranged from 385 to 590 pounds per acre. Lint turnout ranged from 39 to 43 percent. ALABAMA AGRICULTURAL EXPERIMENT STATION Stands were lower at the first planting date with little difference between varieties at 10 days after planting (10 DAP), but differences were apparent for the 21 DAP count, particularly for the second and third planting dates. Both planting date and cultivar had significant effects on yield, with no interactions between them. Most lint quality measurements were significantly different for varieties, or for an interaction of variety and planting date. Further testing will be needed to determine if these varieties have the potential to allow earlier planting for producers. Cold-Tolerant Varieties by Planting Dates, Prattville Agricultural Research Unit, 2004 PLANTING DATE Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 3 Planting Date 3 Planting Date 3 Planting Date 3 LSD (P=.10) VARIETY CT 110 HQ CT 212 HQ FM 958 DP 491 CT 110 HQ CT 212 HQ FM 958 DP 491 CT 110 HQ CT 212 HQ FM 958 DP 491 10DAP 21DAP LINT YIELD Plants/56' Plants/56' lb/a 44 44 40 29 55 57 58 55 56 55 52 53 11 61 75 56 52 143 152 139 146 150 156 118 132 16 442 566 427 590 442 526 530 655 415 492 385 466 97 TURNOUT % 41 40 42 43 39 40 42 43 40 41 42 43 0.7 MIC* units 4.1 4.1 4.5 4.6 4.2 4.6 4.6 4.6 4.2 4.9 4.7 4.7 0.3 LENGTH inches 1.15 1.09 1.12 1.14 1.13 1.07 1.10 1.13 1.13 1.08 1.12 1.16 0.04 STRENGTH g/tex* 30.4 28.5 31.1 29.9 28.4 27.3 29.9 29.4 29.2 29.2 29.7 30.1 1.1 UNIF* % 83 82 83 83 82 81 82 82 82 81 82 82 1 *G/tex=Grams per tex; Mic=micronaire; Unif. =uniformity. 2004 COTTON RESEARCH REPORT 15 EVALUATION OF COLD-TOLERANT AND CONVENTIONAL COTTON VARIETIES AND PLANTING DATES AT THE WIREGRASS RESEARCH AND EXTENSION CENTER D.P. Delaney, C.D. Monks, Brian Gamble, Larry Wells, and K. Glass Seed for cotton cultivars currently grown in Alabama require warm soils in order to germinate and develop properly. Soil temperatures must remain above 60° F for several days, which normally occurs after early April in much of the state. Producers who plant early in the season run the risk of poor stands 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 may set bolls before soil moisture is depleted by hot weather. In southeast Alabama, this may allow some cotton harvest before peanut harvest begins. Recently released "coldtolerant" cotton varieties are claimed to germinate and grow well at temperatures well below the optimum for currently grown varieties and may allow earlier planting and harvest. Two varieties each of "cold-tolerant" and "conventional" cotton cultivars, as well as two "stacked gene" varieties were planted on each of three planting dates at the Wiregrass Research and Extension Center (WREC) in Headland, Alabama. One variety of each type was designated by the respective seed company as early maturity and the other mid- to full season. Four replications of four 36-inch rows by 20-foot long plots of each variety were planted on April 1 and 16 and May 5, 2004, using a conventional-till production system. Fertility and pesticide applications were made according to Alabama Cooperative Extension System recommendations. Rainfall was plentiful through most of the season. Due to the approach of Hurricane Ivan, the all treatments at maturity were defoliated and machine-harvested four days later. Those plots were picked a second time 16 days later, along with the remaining varieties had after defoliation. A one-pound Table 1. Lint Quality, Cold-Tolerant Varieties by Planting Dates, WREC, 2004 TREATMENT Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 3 Planting Date 3 Planting Date 3 Planting Date 3 Planting Date 3 Planting Date 3 LSD (P=.10) *g/tex=grams per tex; Mic=micronaire; Unif. =uniformity. CULTIVAR CT 110 HQ CT 212 HQ FM 958 DP 449 BG/RR DP 444 BG/RR DP 491 CT 110 HQ CT 212 HQ FM 958 DP 449 BG/RR DP 444 BG/RR DP 491 CT 110 HQ CT 212 HQ FM 958 DP 449 BG/RR DP 444 BG/RR DP 491 MIC* units 4.6 4.5 4.5 4.6 4.1 4.4 4.3 4.3 4.5 4.4 4.1 4.1 4.1 4.2 4.4 4.0 3.9 4.2 0.3 LENGTH inches 1.14 1.14 1.16 1.14 1.13 1.16 1.17 1.11 1.15 1.11 1.15 1.17 1.15 1.14 1.16 1.13 1.16 1.17 0.03 STRENGTH g/tex* 28.3 29.3 29.9 30.8 28.8 30.4 29.8 29.1 31.2 29.8 29.4 31.4 30.2 31.0 30.8 30.9 29.7 30.7 1.1 UNIF.* % 82.5 82.8 82.8 82.5 83.3 83.0 83.5 82.3 83.0 82.8 83.8 83.5 82.5 82.8 83.0 82.5 83.8 83.5 1.0 16 ALABAMA AGRICULTURAL EXPERIMENT STATION Table 2. Stands and Yield, Cold-Tolerant Varieties by Planting Dates, WREC, 2004 7 DAP* plants/40´ 62 63 23 28 59 26 92 101 64 77 102 74 78 87 63 74 81 73 26 21 DAP plants/40´ 121 122 72 125 127 105 146 128 135 142 120 135 122 126 125 117 130 120 27 LINT YIELD lb/A 1,269 2,006 1,484 1,796 1,859 1,295 1,389 1,246 1,501 1,251 1,989 1,457 1,256 1,212 1,325 1,328 1,258 1,267 283 FIRST PICK TREATMENT Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 1 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 2 Planting Date 3 Planting Date 3 Planting Date 3 Planting Date 3 Planting Date 3 Planting Date 3 LSD (P=.10) *DAP = Days after planting VARIETY CT 110 HQ CT 212 HQ FM 958 DP 449 BG/RR DP 444 BG/RR DP 491 CT 110 HQ CT 212 HQ FM 958 DP 449 BG/RR DP 444 BG/RR DP 491 CT 110 HQ CT 212 HQ FM 958 DP 449 BG/RR DP 444 BG/RR DP 491 YIELD % 76 78 82 86 88 70 80 100 70 100 92 100 100 100 100 100 100 100 8 TURNOUT % 42 41 41 41 42 42 41 41 41 41 42 42 40 40 41 41 43 43 1 grab sample from each plot was ginned on a mini-gin for lint quality and turnout, and lint was analyzed for quality by HVI at the USDA-AMS lab at Pelham, Alabama (Table 1). Plant stands improved from the first to the second planting dates on the seventh day after planting (7 DAP) count (Table 2), but decreased for the third date due to heavy rains after planting, with some variety differences. Yields tended to be higher for the first planting date, and the early varieties of second planting date which could be picked before the hurricane, although there were statistical interactions between varieties and planting dates for yield. Those varieties with a "first pick" percentage of less than 100 percent were harvested for the first time before the hurricane. Micronaire was higher with early planting, while strength increased with later planting (Table 1). Varieties differed in all quality measurements, but there were no interactions between planting date and the variety for quality. Further testing will be needed with machine harvesting to determine if these varieties have the potential to allow earlier planting and economical yields for producers. 2004 COTTON RESEARCH REPORT 17 ON-FARM COTTON VARIETY EVALUATIONS, 2004 C.D. Monks, C.H. Burmester, W.C. Birdsong, R.W. Colquitt, D. E. Derrick, W.G. Griffith, L K. Kuykendall, R.L. Petcher, R.P. Yates, and J. Clary The primary objective of this study was to provide producers with unbiased (third-party) information on the performance of recently released cotton varieties. While seed company and university small plot trials are very useful, on-farm trials provide further information on how specific varieties will perform when evaluated under growers' production systems. These trials also provide an opportunity to broaden the scope of evaluations to different soil textures not found on university research sites. Each year, the Alabama Experiment Station System conducts cotton variety trials at five locations (experiment stations) in the state. These trials are established using four replications in a randomized complete block design with two-row plots, 25 to 30 feet in length. The results of these trials allow producers to compare relative differences among a large number of varieties, enable researchers to build a long-term data base on specific varieties, and provide a consistent picture of performance because the tests are conducted using uniform techniques from location to location. Seed companies are also very active in establishing on-farm variety strip trials. However, producers continue to be adamant in their need for unbiased data from on-farm variety systems trials with which to compare industry data. In 2004, eight on-farm variety trials were established in the following counties in Alabama: Barbour, Dale, Cherokee, Shelby, Elmore, Perry, Macon, and Coffee (Table 1). Each trial was planted, maintained, and harvested using producer equipment and methods. The Barbour and Macon trials were planted in irrigated fields while the others were planted under dryland production. The trials were machine-harvested and seed cotton weights were recorded. After harvest, seed cotton was ginned on a small 10-saw research gin (without lint or stick cleaners) and quality analysis conducted by the USDA Cotton Classing office in Birmingham, Alabama. Environmental conditions for most of the growing season resulted in a very high state yield average of 729 pounds per acre that was of high quality. However, the following locations were not harvested or data not presented due to severe mid-September storm damage from Hurricane Ivan: Coffee, Dale, and Perry counties. Lint yields and quality for each location are presented in tables 2-6. An overall summary of variety performance (yield rankings) for the north and central Alabama locations is presented in Table 7. Included in this table are Table 1. On-farm Variety Evaluations in Alabama, 2004 comparisons with yield rankings from DATA HARVEST selected Alabama and Georgia state LOCATION REA/CEC* PRODUCER REPS. CROP TABLE DATE variety trials. DP 555 BG/RR and FM 991 BR Cherokee Co. Derrick 2 McMichen 4 Dryland 9/29 were among the highest performers in most of the trials. At several locaElmore Co. Kuykendall 3 Peoples 4** Dryland 9/13 tions, the mid- to full-season varieties yielded higher when compared to Colquitt, Shelby Co. 5 Barber 2*** Dryland 10/2 early-season entries. This is likely a Griffith result of storm damage to early-maturPerry Co. Yates Kish 1 Dryland NA ing varieties that would have had more open bolls compared to the laterMacon Co. Clary 4 Walters 1 Irrigated 10/13 maturing entries. This type of data is useful for Coffee Co. Petcher Hussey 1 Dryland **** Alabama cotton producers to compare varieties over a range of soil textures Dale Co. Birdsong Williams 2 Dryland **** and environments. An interesting comparison of technology indicated that, in general, the BG/RR stacked Barbour Co. Birdsong 6 Corcoran 2 Irrigated 10/8 gene combination performed better *Regional Extension Agent or County Ext. Coordinator, Alabama Cooperative Extension when compared to its BGII/RR counSystem. **Harvested as two bulked replications. ***Harvested as one bulked replication. ****Harvested but not reported due to storm damage. terpart. Additional data are required in 18 ALABAMA AGRICULTURAL EXPERIMENT STATION Table 2. Summary of Turnout, Yield, and Quality for Cherokee County, 2004* VARIETY DP 555 BG/RR FM 960 BG/RR ST 5599 BR DP 432R DP 434R BCG 28R PERCENT TURNOUT LINT YIELD lb/a 1,499 1,455 1,415 1,373 1,325 1,322 1,307 1,300 ** YIELD 1 2 3 4 5 6 7 8 RANK 44 43 40 42 43 40 42 41 40 order to further compare the performance of the BGII/RR technology (Table 7). Producers understand that varieties can perform differently under varying environmental conditions. The excellent growing conditions and low insect pressure present in 2004 resulted in excellent yields in most of the trials. DP 444 BR ST 5242 BR PHY 410R ** *Each individual plot was approximately 1400 feet long by four rows wide. Due to a low area in the field, this yield was not included in the report. Table 3. Summary of Turnout, Yield, and Quality for Elmore County, 2004* VARIETY DP 555 BG/RR FM 991 BR FM 991 RR DP 494 RR ST 5599 BR ST 5242 BR DP 488 BG/RR PHY 410R FM 960 BR FM 989 RR FM 991 B2R FM 960 RR PHY 510R DP 449 BG/RR DP 434 RR ST 5303 R ST 4892 BR DP 451 B/RR DP 432 RR ST 4793 RR PERCENT TURNOUT LINT YIELD lb/a 1,074 1,010 1,000 985 980 937 922 916 903 902 902 898 892 880 878 870 846 805 797 696 YIELD 1 2 3 4 5 6 7 8 9 RANK MICRONAIRE 5.0 4.6 4.6 4.6 4.8 4.7 4.6 5.0 4.9 4.4 4.3 4.4 4.8 4.8 4.3 5.0 4.6 4.8 4.6 5.0 LENGTH 35 34.5 34.5 36 35.5 33 36.5 34 33.5 34 36 34.5 35 34.5 35.5 34 34 34 34.5 35 STRENGTH 28.6 32.9 31.1 31.9 30.2 28.8 31.4 30.5 30.9 32.0 30.3 28.6 30.4 30.7 28.1 29.6 31.0 27.6 31.0 29.2 UNIFORMITY 81 83.5 82 83 81.5 83 82.5 83.5 82 82 82.5 83 82 83 82.5 83 83 81.5 82.5 82.5 42 38 39 41 42 43 41 41 41 40 37 42 38 39 41 39 43 37 40 41 10 11 12 13 14 15 16 17 18 19 20 *Each individual plot was approximately 1,200 to 1,700 feet long by four rows wide. Four plots per variety were planted and yields were combined at harvest on Sept. 13. 2004 COTTON RESEARCH REPORT Table 4. Summary of Turnout, Yield, and Quality for Macon County, 2004* VARIETY FM 991BR DP 488 BG/RR DP 494 RR DP 434 RR DP 555 BG/RR FM 960B2R PHY 510R DP 432 RR FM 960BR ST 4892 BR DP 449 BG/RR ST 5242 BR ST 5599 BR FM 991B2R PHY 410R ST 5303 R DP 444 BG/RR ST 4646 B2R PERCENT TURNOUT 19 LINT YIELD lb/a 1,406 1,328 1,328 1,311 1,300 1,253 1,241 1,220 1,219 1,188 1176 1,163 1,147 1,134 1,076 1,066 1010 875 YIELD 1 2 3 4 5 6 7 8 9 RANK MICRONAIRE 4.4 4.3 4.4 4.2 4.2 4.7 4 4.1 4.4 4.3 4.2 4.3 4.4 4 4.6 4.7 3.7 4.2 LENGTH 35 37 37 36 35 36 36 35 35 34 36 35 35 37 35 34 36 35 STRENGTH 32.7 30.7 30.6 27.9 28.7 28.9 30.5 29.6 32.1 27.7 29.4 27.8 29.3 32.2 28.9 31.6 30 28.6 UNIFORMITY 83 83 82 83 82 83 82 83 82 83 84 83 82 82 84 83 83 82 41 42 44 44 45 43 40 43 40 45 42 43 42 40 41 42 43 42 10 11 12 13 14 15 16 17 18 *Each individual plot was approximately 800 to 900 feet long by four rows wide. One plot per variety was planted and harvested on October 13. Table 5. Summary of Turnout, Yield, and Quality for Shelby County, 2004* VARIETY FM 991 BR DP 449 BG/RR DP 555 BG/RR DP 432 RR ST 5599 BR DP 488 BG/RR PHY 510R DP 494 RR FM 960 BR FM 991 B2R DP 434 RR ST 4892 BR DP 444 BG/RR FM 960 B2R ST 5242 BR ST 5303 R ST 4646 B2R PHY 410R PERCENT TURNOUT LINT YIELD lb/a 1,137 1,135 1,117 1,113 1,106 1,095 1,084 1,064 1,063 1,063 1,045 1,041 1039 1,009 988 975 947 938 YIELD 1 2 3 4 5 6 7 8 9 RANK MICRONAIRE 4.6 4.7 4.9 4.9 4.9 4.7 4.5 4.9 4.8 4.5 4.7 5.3 3.9 4.8 4.2 4.5 4.6 4.6 LENGTH 35 34 34 34 35 37 35 36 33 35 35 33 34 36 34 36 34 36 STRENGTH 30.1 30.5 28.1 28.1 28.7 30.5 30.2 30.6 32.1 31.4 27.3 26.7 28.2 31.2 27 31.7 28.8 29.9 UNIFORMITY 82 83 82 83 83 83 81 83 82 83 83 83 83 81 83 84 81 83 42 43 47 43 43 44 42 44 43 41 47 44 44 42 42 41 40 43 10 11 12 13 14 15 16 17 18 *Each individual plot was approximately 1,400 to 1,500 feet long by four rows wide. Two plots per variety were planted and yields were combined at harvest. 20 ALABAMA AGRICULTURAL EXPERIMENT STATION Table 6. Summary of Turnout, Yield, and Quality for Barbour County, 2004* VARIETY SG 215 BRR DP 451 BRR DP 424 B2RR DP 488 BRR DP 444 BRR FM 960 B2RR DP 449 BRR FM 991 B2RR DP 432 RR DP 494 RR DP 458 BRR FM 991 BRR DP 434 RR ST 4892 BRR DP 555 BRR PSC 410 RR ST 5599 BRR ST 4646 B2RR FM 960 BRR ST 4793 RR PSC 510 RR ST 5303 RR DP 5690 RR FM 991 RR DP 5415 RR DP 436 RR FM 960 RR ST 5242 BRR LINT YIELD/A 1,249 1,213 1,190 1,188 1,167 1,141 1,134 1,131 1,123 1,109 1,097 1,081 1,076 1,027 1,027 1,015 1,022 1,003 1,003 992 982 975 972 941 936 907 893 898 YIELD RANK 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 RETURN/ACRE 669.48 662.91 654.86 652.22 643.89 627.28 623.5 622.46 615.79 610.48 600.37 595.75 588.35 563.34 562.69 557.76 557.61 552.32 552.13 539.61 537.35 535.60 535.22 517.80 513.12 494.36 492.74 486.63 MICRONAIRE 4.45 3.8 4.1 4.4 3.75 4.3 4.15 4.05 4.5 4.4 4.2 4.4 4.05 4.6 4.35 4.35 4.25 3.95 4.1 4.45 4.55 4.1 4.3 4.1 4.5 4.1 3.85 4.2 LENGTH 34.5 36 36.5 37 36.5 37 36.5 38 36 37.5 36.5 37 37 35.5 36.5 36.5 35.5 36 35.5 36 37 35.5 37 37.5 36 37 37.5 35 STRENGTH 28.4 29.8 30.95 31.5 31.5 34 32.2 33.55 29.65 33.1 31.2 33.05 29.45 31.45 30.55 31.9 30.25 30.25 33.95 29.8 30.8 33.5 33.1 32.25 31.05 28.4 32.4 28.9 UNIFORMITY 83.5 82 83.5 83 83.5 82.5 83 83 83.5 83.5 81.5 83.5 82.5 84.5 82 84.5 82.5 82 83.5 83.5 83 83.5 83 83 83 83 83 83 *Each individual plot was approximately 1,000 feet long by four rows wide. Two plots per variety were planted and yields were combined at harvest. Table 7. Relative Yield Rankings by Location, 2004* ALABAMA ON-FARM TRIALS VARIETY DP 432 RR DP 434 RR DP 444 BG/RR DP 449 BG/RR DP 488 BG/RR DP 494 RR DP 555 BG/RR FM 960 BR FM 960 B2R FM 991 BR FM 991 B2R ST 4892 BR ST 5242 BR ST 4646 B2R ST 5599 BR ST 5303 R PHY 410R ELMORE 19 15 NA 14 7 4 1 9 NA 2 11 17 6 NA 5 16 8 MACON 8 4 17 2 2 3 5 9 6 1 14 10 12 18 13 16 15 SHELBY 4 11 13 2 6 8 3 9 14 1 10 12 15 17 5 16 18 CHEROKEE 4 5 7 NA NA NA 1 2 NA NA NA NA 8 NA 3 NA 9 TVS 2 16 4 26 4 5 19 1 20 17 24 10 21 27 2 8 19 STATE VARIETY TRIAL RESULTS EVS 1 7 20 9 2 9 6 5 4 21 16 11 13 14 3 18 23 WGS 4 10 27 5 9 4 6 8 20 13 17 13 20 25 18 23 18 TIFTON 15 7 19 13 5 9 10 6 32 15 25 8 18 24 16 2 9 *Rankings as reported within their respective early or full-season trial location. The varieties listed first within each company were in the early season state variety trials (SVTs) and those listed below each company's line were in the full-season SVTs. 2004 COTTON RESEARCH REPORT 21 CROP PRODUCTION ROTATING COTTON WITH NON-HOST CROPS TO CONTROL RENIFORM NEMATODES W.S. Gazaway, K.S. Lawrence, and J.R. Akridge Cotton farmers have routinely relied on nematicides to control reniform nematodes. Although effective in the short term, nematicides are expensive and do not always produce the desired economic returns. Since there are no commercial cotton varieties with resistance to reniform nematodes, rotation with non-host crops provides the only reliable alternative for their management. Two previous rotation studies indicated that one-year and/or two-year corn or peanut rotations can effectively reduce reniform nematodes to a manageable population. Moreover, rotating with non-host crops has also improved weed control, soil fertility, and soil texture. However, we need to determine if the use of nematicides in cotton following a one-year or two-year rotation with peanut or corn will improve cotton yields. A multiyear project to make this evaluation began in 2004. The project was placed in a cotton field that was thought to be heavily infested with reniform nematodes. Rotation/nematicide treatments are summarized in the table. The test is a factorial arrangement of a randomized complete block design, with summer rotation crops as the main factor (eight-row plots). Cotton following peanut or following corn are split into two four-row subplots. One of the two subplots was randomly selected and treated with a nematicide. The other subplot did not receive a nematicide. Continuous cotton receiving a nematicide and continuous cotton not receiving a nematicide were divided into fourrow plots. The test is replicated five times. The entire field will be planted each fall with a rye winter cover crop that will be cut prior to planting the summer crops. Summer crops will be planted in a strip-till into the rye stubble. The nematicide/fumigant, Telone II, will be injected into the strip area using a Yetter applicator seven to 14 days prior to planting. The 2004 rotation study was destroyed just prior to harvest by a hurricane. Winds of 115 miles per hour hit the test area, blowing cotton in open bolls to the ground and plants that had unopened bolls flat on the ground. Consequently, yield data could not be taken. Moreover, nematode populations in this new area were scattered more than our initial soil tests had indicated, making a comparison between rotation schemes impossible. An attempt to obtain uniform nematode distribution in the test area by artificially inoculating with reniform nematodes was unsuccessful. Consequently, the rotation study will be moved in 2005 to a new location that has a more uniform distribution of reniform nematodes. Alternative Cropping/Nematicide Schemes to Control Reniform Nematodes in Cotton NEMATICIDE/INSECTICIDE1 2004 Cont.2 cotton/ nematicide Cont. cotton Peanut-1 yr/nematicide Peanut-1 yr Peanut-2 yr/nematicide Peanut-2 yr Corn-1 yr/nematicide Corn-1 yr Corn-2 yr/nematicide Corn-2 yr cotton(N) cotton peanut(N) peanut peanut peanut corn corn corn corn 2005 cotton(N) cotton cotton(N) cotton peanut peanut cotton (N) cotton corn corn SUMMER 2006 cotton(N) cotton peanut peanut cotton(N) cotton corn corn cotton(N) cotton CROPS 2007 cotton(N) cotton cotton(N) cotton peanut peanut cotton(N) cotton corn corn 2008 cotton(N) cotton peanut peanut peanut peanut corn corn corn corn 2009 cotton(N) cotton cotton(N) cotton cotton(N) cotton cotton(N) cotton cotton(N) cotton 1Cotton treated with nematicide (N), Telone II, at three gallons per acre using a Yetter rig, for nematode control or with insecticide, Di-Syston 15, at seven pounds per acre in the furrow at planting for early season insect control. Note: No nematicides will be used in peanut or corn plots. 2Cont.=Continuous. 22 ALABAMA AGRICULTURAL EXPERIMENT STATION SUBSURFACE DRIP IRRIGATION (SDI) TAPE PRODUCTS AND FERTIGATION, TENNESSEE VALLEY RESEARCH AND EXTENSION CENTER L.M. Curtis, C.H. Burmester, D.H. Harkins, and B.E. Norris A subsurface drip irrigation (SDI) study initiated in 1998 at the Tennessee Valley Research and Extension Center in Belle Mina, Alabama, was designed to compare five different drip irrigation tape products with a fertigation component included. This study was installed in an area where continuous crops have been produced for many years. Emitters were located two feet along the tape, with tape buried 15 inches between every other row. Rows 340 feet in length were used to better simulate field conditions. Fertilizer management for each tape product was evaluated using a single (conventional) surface-applied sidedress versus multiple sidedress applications injected through the SDI system. A tape product was also used on the surface using a conventional fertilizer treatment. Fertility treatments in 2004 are indicated in Table 1. The varieties selected each year were DPL 33B (1998 and 1999), DPL 428B (2000 and 2001), DPL 451BR (2002 and 2003), and DP 444BG/RR (2004). Fertigated yields were less in 2004 compared to conventional fertilization. Wet conditions throughout the growing season made surface-applied fertilizer readily available. The dryland treatment yielded less than irrigated treatments, but this may be attributed to the lower quantity of fertilizer on dryland plots in a year with abundant rainfall. In 1998, little difference between fertility treatments was observed. In 1998, sufficient rainfall occurred late in the growing season so that fertilizer in the upper layTable 1. Fertility Treatments in 2004 IRRIGATED CONVENTIONAL ers of the soil was more readily available. In 1999, extremely dry conditions in the upper layers of the soil profile made conventionally applied fertilizer less available, resulting in yield reduction compared to fertilizer applied through the irrigation system. In 2001, initiation of fertigation through the tape was inadvertently delayed more than two weeks. Even though the fertigation schedule was modified to ensure that all scheduled fertilizer was applied, the delay reduced fertigated yields. Yields in 2002 were similar to previous years, with little difference in fertilizer treatments but significant yield improvement over the nonirrigated treatment. In 2003, fertigated treatment yields were reduced for three of the tape products when compared to conventional fertility treatments. This difference may be related to very wet conditions through much of the growing season, resulting in shallow root development with less uptake of nutrients from the 15-inch depth where the drip tape was installed and where fertigation delivered nutrients. This possibility is speculative, however, and is not based on field measurements. Significant yield differences were observed each year between nonirrigated plots and tape plots with fertility treatments. Figures 1 and 2 illustrate yield results for 1998 through 2004 for conventional and fertigated treatments. Average yields for the seven years are shown in Table 2. NON-IRRIGATED DRIP TAPE ON SURFACE1 NA NA 30# N on cover crop 60# N FERTIGATED Preplant Sidedress2 30# N on cover crop 120#N + 60#K 30# N on cover crop 120#N + 60#K 1 The surface tape treatment was discontinued after 2000 because of damage and leaks caused by insects and animals. 2All sidedress was applied at early to mid square for conventional and dry tape treatments; the sidedress treatment was divided into eight equal applications for the fertigated treatments beginning at early to mid-square. 2004 COTTON RESEARCH REPORT Table 2. Seven-Year Average per Tape Treatment POUNDS SEED COTTON CONVENTIONAL Not irrigated Surface T-Tape1 T-Tape Raintape Netafim Eurotape 2,149 3,545 3,391 3,499 3,475 3,500 3,373 3,467 3,454 3,528 PER 23 ACRE FERTIGATED 1 The surface tape treatment was discontinued after 2000 because of damage and leaks caused by insects and animals. DRIP Drip Tape Comparison Figure 1. Conventional Fertility Program and TAPE COMPARISON 4500 POUNDS SEED COTTON PER ACR 4000 3500 3000 2500 2000 1500 1000 500 0 1998 1999 2000 2001 2002 2003 2004 CONVENTIONAL FERTILITY PROGRAM AND TAPE COMPARISON FIGURE 1 NO T IR R SU R IG AT ED FA CE TTA PE TT AP E RA IN T AP E NE TA FI LM EU R O TA PE TAPE PRODUCT Figure 2. Fertigated Program and Tape Comparison TAPE COMPARISON FERTIGATED PROGRAM AND 4500 4000 POUNDS SEED COTTON PER ACR 3500 3000 2500 2000 1500 1000 500 0 T-TAPE RAINTAPE TAPE PRODUCT NETAFILM EUROTAPE 1998 1999 2000 2001 2002 2003 2004 FIGURE 2 24 ALABAMA AGRICULTURAL EXPERIMENT STATION SUBSURFACE DRIP IRRIGATION (SDI) PLACEMENT AND IRRIGATION WATER REQUIREMENTS, TENNESSEE VALLEY RESEARCH AND EXTENSION CENTER L.M. Curtis, C.H. Burmester, D.H. Harkins, and B.E. Norris This experiment was initiated in 1998 to evaluate placement of sub4500 surface drip irrigation 4000 (SDI) relative to crop 3500 row direction and to 3000 evaluate water require2500 ments for cotton produc2000 1500 tion using SDI. Drip tub1000 ing was buried 15 inches 500 deep with emitters at 0 two-foot intervals along the tubing. Tubing placement treatments were (1) between every other row-80-inch spacing between drip lines and (2) perpendicular to rows-80-inch spacing between drip lines. The varieties selected each year were DPL 33B (1998 through 2001) and DPL 451BR (2002 through 2004). Irrigation treatments were based on daily applications equal to 30 percent, 60 percent, and 90 percent of pan evaporation after full crop canopy, with adjustments based on percent canopy prior to full canopy cover. Yield results for seven years (1998 through 2004) are presented in Figure 1. Yields in 2004 were little affected by irrigation, and dryland yields equaled or exceeded irrigated yields. Significant yield increases were achieved with SDI for four out of the seven years of this study, with average yields over these seven years as shown in the table. The average over all irrigation treatments for the seven years was 976 pounds of seed cotton per acre greater than the seven-year average for the non-irrigated treatment. POUNDS SEED COTTON PER ACR N O T IR R IG ED AT DRIP PLACEMENT AND IRRIGATION SCHEDULING FIGURE 1 1998 1999 2000 2001 2002 2003 2004 % 30 PE R N PE D IC U PERPENDICULAR (T) vs BETWEEN ROWS (II) Average Yield over Seven Years TREATMENT Non-irrigated 30% pan, perpendicular to rows 60% pan, perpendicular to rows 90% pan, perpendicular to rows 30% pan, between rows 60% pan, between rows 90% pan, between rows POUNDS SEED COTTON PER ACRE 2,558 3,226 3,516 3,694 3,343 3,729 3,697 % 60 PE R N PE D IC U LA R % 90 PE R N PE D IC U LA R % 30 BE TW N EE RO LA R % 60 BE TW N EE RO W % 90 BE TW N EE RO W W 2004 COTTON RESEARCH REPORT 25 EVALUATION OF PRESSURE-COMPENSATING SUBSURFACE DRIP IRRIGATION (SDI) ON ROLLING TERRAIN FOR COTTON PRODUCTION L.M. Curtis, J.P Fulton, J.N. Shaw, R. Raper, C.H. Burmester, B.E Norris, and H.D. Harkins A study was established at the Tennessee Valley Research and Extension Center (TVREC) in Belle Mina, Alabama, during 2003 to evaluate the use of subsurface drip irrigation (SDI) on rolling terrain. One objective of the study is to evaluate cotton production on rolling terrain at the TVREC with subsurface drip irrigation (SDI) in conjunction with two reducedtillage practices. The other is to evaluate SDI installation and farming practices carried out using precision-guidance equipment and harvest correlated with terrain features using yield-monitoring equipment. Installation of the SDI system was initiated in late fall and winter 2003 and was completed in late spring 2004. Because a component of this study was no tillage with a cover crop, the installation process disturbed the area, and wet weather delayed installation and planting the cover crop, we decided to treat the entire area uniformly in 2004. Stoneville 4892 BR was planted on the 14-acre area, with conventional fertility practices carried out. Yield mapping at harvest indicated very uniform production throughout the field, with an overall yield of 3.2 bales (1,562 pounds of lint) per acre. SPRINKLER IRRIGATION WATER REQUIREMENTS AND IRRIGATION SCHEDULING, TENNESSEE VALLEY RESEARCH AND EXTENSION CENTER L.M. Curtis, C.H. Burmester, D.H. Harkins, and B.E. Norris SEED COTTON PER ACRE This experiment was established in 1999 to evaluate a range of irrigation application capabilities to identify the minimum design flow rate that will produce optimum yields. Treatments included four sprinkler irrigation capabilities and a nonirrigated treatment. Irrigation was managed using soil moisture sensors and Moiscot, a spreadsheet-based scheduling method. The irrigation capabilities were (1) one inch every 12.5 days, (2) one inch every 6.3 days, (3) one inch every 4.2 days, and (4) one inch every 3.1 days. These irrigation capabilities are equivalent to 1.5, 3, 4.5, and 6 gallons per minute per acre. The one-inch amount represents the maximum amount of irrigation that could be applied in the time indicated. The varieties selected each year were as follows: DPL 33B (1999), DPL428B (2000 and 2001), and DPL 451BR (2002 through 2004). The results for 1999 through 2004 are presented in the figure. In 2004, rainfall was plentiful Figure 1. Sprinkler Irrigation Cotton Yield Results SPRINKLER throughout the growing season, and dryland and irrigated yields were not COTTON YIE substantially different. The average FIGU yields for the six-year period in pounds 4500 of seed cotton per acre were: 1999 Nonirrigated = 2,429 lb/a; 2000 1 inch = 12.5 days, 2,980 lb/a; 4000 2001 1 inch = 6.3 days, 3,303 lb/a; 2002 1 inch = 4.2 days, 3,505 lb/a; 2003 3500 1 inch = 3.1 days, 3,492 lb/a. 2004 In 2003, rainfall was near optimum through much of the growing season, 3000 but a 26-day dry period occurred between August 7 and September 4. A 2500 total of only 0.61 inches of rain occurred during this period, and this rainfall was measured in seven minor 2000 rainfall events. Three timely one-inch 26 irrigation applications during this period boosted irrigated yields, with 476 additional pounds of seed cotton per acre on the optimum irrigation treatment (one inch every 4.2 days). In 2002, irrigated yields were significantly higher than nonirrigated yields, but the highest yields were less than in other years for most treatments. The reason for ALABAMA AGRICULTURAL EXPERIMENT STATION this is unclear but may be related to shutdown of irrigation prior to sufficient boll maturity. Only very small yield differences were noted in 2001, while significant differences were measured in 1999 and 2000. Rainfall variability and treatment effects accounted for the wide range of yield responses for each of these years. FIFTY YEARS OF SOIL TESTING FOR COTTON IN ALABAMA C.C. Mitchell and K.B. Holland A summary of 50 years of public soil testing by Auburn University indicates that Alabama cotton producers are, in general, doing a very good job of maintaining a desirable soil pH and "high" soil test values for phosphorus (P), potassium (K), and magnesium (Mg) for optimum production. The Auburn University Soil Testing Laboratory in 2004 celebrated 50 years of service to Alabama farmers by moving into a new facility. The new Alfa Agricultural Services Building on the Auburn University campus houses soil testing, plant analysis, feed and forage analysis, manure analysis, environmental testing, nematode assay, and plant diagnostic services. When soil testing began in 1953, it was mostly a service for cotton and corn producers. Soon afterward, other crop recommendations were added. In 2004, more than 50 crop recommendations were included, with cotton samples accounting for 13 percent of total recommendations. Soil testing records or summaries of records have been kept since the laboratory began operation in 1954. Some of these records have been lost and some old computer records are difficult to recover. However, enough old summaries and data were recovered to make some general statements regarding the trends in soil fertility for cotton in Alabama. We estimate that about onethird to one-half of all commercial agricultural samples in Alabama are being tested by private laboratories. Decreasing numbers of soil samples since the early 1980s reflect decreasing row-crop acreage in Alabama (Figures 1 and 2). However, acreages of cotton, peanuts, and hay have remained fairly constant during this time period (Figure 2). Acid soil infertility has always been a concern of Alabama cotton producers, and regular ground limestone applications are part of their routine production inputs. Extremely acid soils (pH< 5.0) are generally less than 1 percent of total soils tested, but they do occur in problem situations (Figure 3). In the mid-1960s, almost 70 percent of samples needed lime (pH<6.0). Today, around 30 percent need lime each year. If we assume that a good cotton farmer may need to apply some limestone every three to five years in order to maintain a soil pH above 5.8, Alabama cotton producers are doing about as good a job of managing soil pH as could be expected. Soils with a pH above 7.0 are usually calcareous soils from the central Alabama Black Belt prairie region. Cotton samples consistently test higher in Mg than other crops (Figure 4). This is probably because cotton farmers generally do a better job of liming their fields, and most use dolomitic limestone or calcitic limestone that is high in Mg. Fewer than 4 percent of all cotton samples need Mg, and these are usually the same samples with a low pH. Farmers have become aware that putting out too much P is expensive and could degrade surface-water quality. Cotton soils testing very high (VH) and high (H) have been trending downward (Figure 5). At the same time, the number of samples testing medium (M) in P have been increasing. The low (L) and very low (VL) values have continued to stay approximately the same over the past 50 years. The slight increase in the number of "high" samples in 2004 may reflect a change in trends due to an increase in conservation tillage practices and P stratification in the soil surface. Potassium nutrition of cotton has been a concern throughout the cotton belt for several years. Alabama has extensive research relating plow layer soil test K to cotton yields, and these trends indicate that soil test K levels have not changed very much since the 1980s (Figure 6). There is a slight trend toward fewer medium (M) and more high (H) testing soils. Since the early 1960s, the AU Soil Testing Laboratory has categorized samples based on their soil texture and/or estimated cation exchange capacity 2004 COTTON RESEARCH REPORT (CEC). Separate calibrations are used for each soil group. Samples from each soil group have remained fairly constant over the 50 years (Table 2). Alabama cotton producers who have their soils tested by the Auburn University Soil Testing Laboratory are, in general, doing a very good job of maintaining a desirable soil pH and "high" soil test values for P, K, and Mg for optimum production. Long-term trends do not indicate any change in the fertility status of Alabama cotton soils. The AU laboratory tests about one sample each year for every 100 acres of cotton proTable 1. Leading Crops Recommendations in 2004 CROP All forage crops Home gardens, lawns, shrubs Cotton Corn Peanut Soybean Commercial vegetables and fruits All other crops and non-crop areas PERCENTAGE 38 23 13 7 5 3 3 8 Loamy soils with CEC 4.7-9.0 cmol/kg Silt loams and clay loams from the Limestone Valley region and soils high in organic matter (CEC 9.0+) Clays from the Black Belt Prairie region (CEC 9.0+ cmol/kg) 39 27 duced in the state. The fact that some records have been kept over the years that allow at least a partial summary of soil test results is a credit to the past and present management of the AU Soil Testing Laboratory. Past directors of the laboratory are Clarence Wilson (1953-57), Dennis Rouse (1957-66), Tom Cope (1966-80), and Clyde Evans (1980-92). Current director is Hamilton Bryant (1993-present). We also wish to acknowledge Julia Zhu, who is making it possible to retrieve electronic soil test summaries for recent years. Table 2. Soil Groups Tested SOIL GROUP Sandy soils with CEC< 4.6 cmol/kg PERCENTAGE 26 31 4 Figure 1. Total Soil SamplesTested Since 1954 and Soil Samples Tested, 1953-2004 Number of Cotton Recommendations Reported Total Number of Sample 80000 70000 60000 50000 40000 30000 20000 Figure 2. Alabama Row Crop Acreage 1975-2003 p g 5000 4000 Peanut Wheat Total samples 1,000 acres 3000 Soybean 2000 1000 Hay Corn Sorghum Cotton Cotton recommendations 10000 0 1960 1990 1950 1970 1980 2000 2010 0 1975 1980 1985 1990 Year 1995 2000 Years Soil pH 80 Percentage of Cotton Sample 70 60 50 40 30 20 10 0 1950 1960 1970 1980 1990 2000 2010 pH <5.0 pH 5.0-6.0 pH 6.0-7.0 pH >7.0 Year Figure 3. Trends in Soil pH for Alabama Cotton Samples Tested 28 ALABAMA AGRICULTURAL EXPERIMENT STATION Figure 4. Trends in Soil Samples Testing "HIGH" in Magnesium. High is defined as Mehlich-1 extractable Mg > 25 mg/kg for soils with a CEC > 4.6 cmol/kg or Mehlich-1 extractable Mg > 12.5 mg/kg for soils with a CEC< 4.6 cmol/kg.) Soil Test Magnesium Percentage testing "HIGH" 100 95 All samples Cotton samples 90 85 80 1980 1985 1990 Year 1995 2000 2005 Phosphorus Levels 70 Percent of Cotton Samples 60 50 40 30 20 10 0 1950 1960 1970 1980 1990 2000 2010 VL L M H VH Figure 5. Trends in Soil Test P for Alabama Cotton Samples. VL= "very low" (Mehlich-1 extractable P< 6 mg/kg); L= "low" (M-1 extractable P = 6 to 12.5 mg/kg); M = "medium" (M-1 extractable P = 13-25 mg/kg); H = "high" (M-1 extractable P = 25 to 50 mg/kg); VH = "very high" (M-1 extractable P > 50 mg/kg). Year Figure 6. Trends in soil test K for Alabama cotton samples. Extractable P values for very low (VL), low (L), medium (M), high (H), and very high (VH) depend upon the soil texture and cation exchange capacity (Adams, et al., 1994). Potassium Levels 70 60 50 40 30 20 10 VL L M H VH Percent of Cotton Samples 0 1950 1960 1970 1980 1990 2000 2010 Year 2004 COTTON RESEARCH REPORT 29 2004 YIELDS: THE OLD ROTATION (CIRCA 1896) AND CULLARS ROTATION (CIRCA 1911) C.C. Mitchell, D.P. Delaney, and K.S. Balkcom The two oldest, continuous field crop experiments in the South continue a trend toward higher yields. Of course, a very favorable 2004 growing season helped. Hurricane Ivan in September 2004 threatened to wipe out what appeared to be a near-record cotton yield, but most plots came through with little damage. An alltime-record cotton lint yield was harvested in early October: 1,650 pounds lint per acre on plot 5 (cottoncorn rotation plus N) on the Old Rotation and 1,950 pounds lint per acre on plot 1 (complete fertilizer/no legume) on the Cullars Rotation. Since 1997, when both of these experiments were converted to high-residue conservation tillage with annual subsoiling coupled with new technology, GMO cultivars, record and near-record yields of every crop have been produced on these two, long-term experiments. The fact that new technology appears to have pushed yield potentials to new plateaus reinforces a conclusion reached in a 1996 paper which looked at 100 years of the Old Rotation. That paper looked at totalfactor productivity and its influence on sustainable cotton production. The authors concluded that ". . . the Table 2. 2004 Old Rotation Yields CLOVER PLOT DESCRIPTION DRY MATTER Table 1. Top Three Record Yields CROP Cotton (lb. lint/acre) OLD ROTATION (YEAR) 1,650 (2004) 1,600 (2001) 1,490 (1994) Corn (bu/A) 236 (1999) 193 (2001) 186 (2004) Wheat (bu/A) 94 (2001) 79 (1999) 73 (2004) Soybean (bu/A) 67 (1996)* 61 (2004) 61 (1992) CULLARS ROTATION (YEAR) 1,930 (2004) 1,570 (1992) 1,550 (2001) 168 (2001) 161 (1999) 155 (1996) 71 (2002) 70 (2001) 65 (2000) 70 (1996)* 65 (2004) 60 (2003) *In 1996, soybean was grown as a full-season crop; normally, soybean is planted double-cropped behind rye or wheat harvested for grain (lb/acre) 1 2 3 4 5 6 7 8 9 10 11 12 13 no N/no legume winter legume winter legume cotton-corn cotton-corn + N no N/no legume cotton-corn winter legume cotton-corn + N 3-year rotation 3-year rotation 3-year rotation cont. cotton/no legume +N (no data due to poor stand and growth) WHEAT (bu/acre) CORN IRRIGATED (bu/acre) CORN NON-IRRIGATED (bu/acre) COTTON COTTON IRRIGATED NON-IRRIGATED (lint/acre) (lint/acre) 620 1,080 1,310 1,330 1,650 390 470 840 980 1,120 1,150 340 SOYBEAN IRRIGATED (bu/acre) SOYBEAN NON-IRRIGATED (bu/acre) 62 52 1,200 1,150 186 72.5 113 60.6 1,450 860 59.8 183 99 1,610 1,180 30 Table 3. 2004 Cullars Rotation Yields P LOT DESCRIPTION CLOVER DRY MATTER (lb/acre) (no data collected due to poor stand) WHEAT (bu/acre) 58.1 21.3 0 46.2 13.8 48.1 43.6 44.9 4 54.1 50.6 116 36.5 ALABAMA AGRICULTURAL EXPERIMENT STATION CORN (bu/acre) 64 40 0 106 25 64 41.1 33 53.2 63 102 1,410 107 COTTON (lint/acre) 1,360 1,060 0 1,930 530 1,830 102 104 0 108 0 1,320 62.6 1,010 SOYBEAN (bu/acre) 63.8 63.3 0 61.8 22 64.2 1,160 46.1 1,270 0 65.1 57.7 A B C 1 2 3 4 5 6 7 8 9 10 11 no N/+legume no N/no legume Nothing no legume no P complete 4/3 K rock P no K 2/3 K no lime no S complete+ micros 1/3 K impact of (new) technology is powerful enough to offset the effect of many other changes in the (production) system" (Traxler et al., 1995). Management is a factor that is difficult to document in long-term experiments but that certainly has an important role to play when documenting long-term yields. In 1997, the USDA-ARS Soil Dynamic Laboratory on the Auburn University campus provided the equipment and some of the labor necessary to maintain the high-residue conservation tillage on these experiments. Increased interest from other researchers and extension specialists and their expertise has contributed to better management of these plots. Support from the Soil Dynamics Laboratory and Alabama commodity funds allowed half of the Old Rotation to be placed under irrigation in 2003; 2004 was the first full season that irrigation was evaluated. Irrigation was applied to cotton, corn, and soybean every other day based upon estimated evapotranspiration. An estimated 15 inches of water was applied during the growing season, beginning in late June. Irrigated cotton plots produced 132 percent of the nonirrigated plots. Irrigated corn produced 163 percent of the nonirrigated corn plots. Although only one treatment is planted to soybean, irrigation did not appear to have any effect on soybean yield. In April 2003, the Cullars Rotation was officially listed on the National Register of Historical Places. (The Old Rotation was listed in 1988.) Posters highlighting this honor and presenting the history of the Cullars Rotation were presented at the 2004 Beltwide Cotton Conference in San Antonio, Texas, and at the 2004 American Society of Agronomy annual meetings in Seattle, Washington. Both the Old Rotation and the Cullars Rotation are maintained through a joint effort of AU's Department of Agronomy and Soils, the Alabama Agricultural Experiment Station, and the USDA-ARS Soil Dynamics Laboratory. Over the years, additional support has come from checkoff funds from the Alabama Wheat and Feed Grains Committee, the Alabama Soybean Committee, and the Alabama Cotton Commission. 2004 COTTON RESEARCH REPORT 31 INSECTICIDES EVALUATION OF GRANULAR INSECTICIDES, SEED TREATMENTS, AND FOLIAR OVERSPRAYS FOR THRIPS CONTROL ON COTTON R.H. Smith Trials were conducted in 2004 at the Prattville Agricultural Research Unit in Prattville, Alabama, to determine the efficacy of granular insecticides, seed treatments, and foliar oversprays in controlling thrips damage. The test was planted on April 15, 2004, using DP 451 BR. The test was set up as a randomized complete block design with four replications. Plots consisted of four rows and were 30 feet long. Materials evaluated as oversprays included Dimethoate, Nufos (Lorsban), and Orthene. Overspray materials were evaluated with and without at-planting treatments of Cruiser, Temik, and Gaucho Grande. The first application of overspray materials was applied at the first true-leaf stage with a backpack sprayer at 10 gallons per acre (gpa) with hollow cone tips. The second overspray application was applied at the third true-leaf stage with a tractor-mounted boom sprayer at 10 gpa with hollow cone tips. Plots were evaluated for thrips populations, plant height, and damage on May 12, 17, 20, and 25, and June 4 and 22. Thrips population assessments were reported as thrips per row foot. Damage ratings were based on a one-tofive scale, with one showing no visible damage and five indicating that all plants have distorted leaves. Plots were evaluated for maturity by counting number of blooms per 30 feet of row on June 22, and counting open bolls on August 9. Due to hurricane damage, no yield results were recorded. Figure 1. Seasonal Average Thrips Populations Seasonal Average Thrips Populatons number of thirps per row/ft. All at-planting treatments showed less thrips injury than the nontreated control on all observation dates. Gaucho Grande was slightly superior to Cruiser, and Cruiser was slightly superior to Temik in this trial. No foliar treatment improved thrips injury in the nontreated at-planting after the first application. Thereafter, all foliar sprays were superior to the nontreated. Of the foliar sprays, Orthene was superior to Dimethoate, which was distinctly better than Nufos. Nufos was the only foliar treatment that did not give acceptable visible results. Nufos looked better following Gaucho and Cruiser than Temik. Nufos over the nontreated at-planting was not very different than the nontreated alone. All at-planting treatments had more blooms on June 22 than did the nontreated at-planting. Temik and Gaucho had slightly more blooms than did the Cruiser. Dimethoate oversprays resulted in more blooms in the Gaucho and nontreated, but not in the Cruiser and Temik treatments. Orthene improved earliness in the nontreated but not after Cruiser, Temik, or Gaucho. Nufos noticeably reduced the number of blooms in the nontreated and all at-planting treatments. Data from this test indicate that Nufos had a definite delaying effect when applied to cotton at the three and five true-leaf stage. Since Nufos appeared to offer the least thrips control of the three overspray products in this test and later appeared to have a crop-maturity delaying effect, it is Figure 2. Seasonal Average Damage Rating Seasonal Average Dam age Rating 5 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 10 9 8 7 6 5 4 3 2 1 0 dimethoate dimethoate dimethoate Untreated Untreated Untreated Untreated dimethoate orthene orthene orthene orthene nufos nufos nufos nufos Untreated Untreated dimethoate dimethoate dimethoate Untreated Untreated dimethoate orthene orthene Untreated Cruiser Temik Gaucho Untreated Cruiser Temik Gaucho orthene orthene nufos nufos nufos nufos 32 Figure 3. Seasonal Average Plant Height Seasonal Average Plant Height 9 8 7 6 5 4 3 2 1 0 dimethoate dimethoate dimethoate Untreated Untreated Untreated Untreated dimethoate orthene orthene orthene orthene nufos nufos nufos nufos ALABAMA AGRICULTURAL EXPERIMENT STATION Figure 4. Bloom Count on June 22 Bloom Count Blooms per 30 ft./row 35 30 25 20 15 10 5 0 Untreated Untreated Untreated Untreated dimethoate dimethoate dimethoate dimethoate inches dimethoate orthene orthene Untreated Cruiser Temik Gaucho Untreated Cruiser Temik Gaucho likely not an acceptable chemical for early-season insect control. The results of the August 9 cracked boll count followed the white bloom count taken on June 22 very closely. At-planting treatments had more open bolls in general than did the nontreated controls atplanting. Gaucho and Temik had more open bolls than did Cruiser. Dimethoate did not improve the earliness of at-planting treatments but did show more open bolls than the nontreated at-planting. Orthene resulted in more open bolls in the nontreated at-planting and Cruiser treatments. However, Orthene did not improve the earliness of Temik or Gaucho. Nufos severely impacted the earliness, in a negative manner, of all three at-planting treatments and where no at-planting treatment was made. The delayed maturity from two oversprays of Nufos at the first and third true-leaf stages was noted throughout the remainder of the season. Figure 5. Cracked and Open Bolls on August 9 Craked and Open Bolls cracked and open bolls per 30 ft./row 60 50 40 30 20 10 0 dimethoate Untreated Untreated Untreated dimethoate dimethoate Untreated orthene orthene orthene orthene nufos nufos nufos nufos Untreated Cruiser Temik Gaucho orthene orthene nufos nufos nufos nufos 2004 COTTON RESEARCH REPORT 33 THRIPS CONTROL ON SEEDLING COTTON B.L. Freeman This trial examined several rates and combinations of Cruiser, Temik, and a potential nematicide, Stan. Cotton, DP 451 BR, was planted on April 19, 2004, on the Tennessee Valley Research and Extension Center in Limestone County, Alabama. Plots were four rows by 25 feet each, and all treatments were replicated four times. Thrips populations were monitored on May 10, 17, and 25, 2004, by rinsing five plants from each plot in a 70-percent ethyl alcohol/water solution. Contents were filtered and examined under a stereoscope. Adult and larval thrips were tallied separately. Thrips pressure during the trial was above average, and conditions for the development of cotton were optimal. The degree of thrips control is compared among treatments in Table 1. In general, Cruiser provided superior control to other treatments, and it was not until the fifth week after planting that the Cruiser-containing treatments averaged more than one thrips per plant. All Table 1. Number of Thrips per Five Plants MAY 10 TREATMENT Cruiser + Stan Cruiser Temik 7.0 lbs. Temik 5.0 lbs. Temik 3.5 lbs. Stan Control A* 1.00 0.00 0.25 0.50 1.25 4.25 6.75 L* 0.50 0.00 2.25 6.75 4.00 22.50 43.75 T* 1.50 0.00 2.50 7.25 5.25 26.75 50.50 % Control 97 100 95 86 90 47 ---A 2.50 3.00 3.00 1.75 2.75 2.75 3.50 Temik treatments averaged one or more thrips per plant at four weeks after planting, and the Temik 3.5 and 5.0 treatments exceeded one thrips per plant at only three weeks after planting. The Stan treatment provided an average of 46 percent thrips control but seemed to contribute little when added with Cruiser. Cotton yields were excellent, and all insecticide/nematicide treatments outyielded the control treatment (Table 2). The five-and seven-pound rates of Temik and the two Cruiser-containing treatments improved yields by 16 to 20 percent (Table 2), while the lowest rate of Temik, and the Stan treatment raised yields by 14 percent and 8 percent, respectively (Table 2). Near-perfect growing conditions throughout the year allowed the cotton plant to compensate for various problems. Despite that, the insecticides in this trial boosted yields by roughly 15 to 20 percent, underscoring that thrips control on seedling cotton is critical. MAY 17 L 0.50 0.25 2.00 6.00 8.25 15.25 42.50 T 3.00 3.25 5.00 7.75 11.00 18.00 46.00 % Control 93 93 89 83 76 61 ---A 4.00 5.50 3.00 3.50 5.75 6.50 11.00 L MAY 25 T 13.25 15.50 18.75 29.50 29.50 45.75 70.00 % Control 81 78 73 58 58 35 ---- 9.25 10.00 15.75 26.00 23.75 39.25 59.00 * A=Adult; L=larval; T=Total Table 2. Seed Cotton Yields TREATMENT Cruiser + Stan Temik 5.0 lb Temik 7.0 lb Cruiser Temik 3.5 lb Stan Control SEED COTTON lb/A 3,983.78 3,936.08 3,911.25 3,862.25 3,791.68 3,583.25 3,323.19 % INCREASE OVER CONTROL 19.88 18.44 17.70 16.22 14.10 7.83 ---- 34 ALABAMA AGRICULTURAL EXPERIMENT STATION HERBICIDES AND DEFOLIANTS COMPARISON OF GLYPHOSATE-TOLERANT AND CONVENTIONAL WEED MANAGEMENT SYSTEMS IN FULL- AND REDUCED-TILLED COTTON M.G. Patterson Glyphosate-tolerant (GT) cotton varieties continue to comprise nearly 90 percent of the cotton acreage in Alabama. As a direct result, the use of reduced-tillage systems, including strip-till and no-till, has increased from 35 percent in 1997 to more than 65 percent. The compatibility of these two technologies has proved both economical and practical, especially as individual farm size has increased. GT varieties have many desirable agronomic traits and yield well. However, some producers have become increasingly concerned with the fiber quality of GT varieties-specifically, high micronaire (fineness) and low staple (length)-versus non-GT varieties. These fiber traits may impact the cash price paid for lint and thus farm profitability. To quantify these concerns, a two-year field study was begun in 2003 to investigate the interaction of tillage system and variety on yield, fiber quality, and net returns. A factorial treatment arrangement of tillage (full vs. reduced) and variety (GT vs. non-GT) in a randomized complete block design with four replications was established at three locations in Alabama. Experimental units were eight rows by 50 feet long. Full-tillage plots were chiseled and disked (two times) prior to planting and included cultivation after crop emergence. Reducedtillage plots were strip-tilled at the E.V. Smith (EVSRC) Research Center in Shorter and the Wiregrass Research and Extension Center (WREC) in Headland, while plots at the Tennessee Valley Research and Extension Center (TVREC) in Belle Mina were true no-till. Varieties were selected based on location and growing season. SG 105 and SG 501RR varieties were used at TVREC. Deltapearl and DP 5415RR varieties were used at the EVSRC and WREC locations. Herbicide programs for each tillage system followed Alabama Cooperative Extension System recommendations and were supplemented on a case-by-case basis, if needed, to maintain good to excellent weed control. Visual estimations of weed control were recorded in late season. Seed cotton was machine harvested and weighed, and subsamples were ginned for fiber analysis (HVI). Gross returns were calculated based on total receipts, including discounts or premiums for fiber quality. A spot price of 60 cents per pound was selected, and herbicide prices were the average of three Alabama chemical retailers. Total weed management costs were estimated for each tillage/weed management system. Lint yield and net returns are presented in Tables 1 and 2. Tillage and weed management system costs varied slightly for the four systems: full-tilled/GT costing $58.65, full-tilled/non-GT costing $58.03, reducedtill/GT costing $47.65 (TVREC) and $57.65 (EVSRC and WREC), and reduced-till/non-GT costing $58.08 Table 1. Cotton Yield (lb lint/a) Response to Variety, Tillage, and Weed Management System in 2003 and 2004 TVREC TREATMENT Full till GT variety Full till Non-GT variety Reduced till GT Variety Reduced till Non-GT variety LSD (.05) 1240 101 1142 ----1413 174 685 126 1806 83 1094 236 1259 1147 1335 829 1427 972 1164 1026 1057 637 1701 1252 1295 1086 1352 826 1498 1018 2003 2004 2003 EVSRC 2004 2003 WREC 2004 2004 COTTON RESEARCH REPORT 35 Table 2. Net Return Response (dollars/a) to Variety, Tillage, and Weed Management System in 2003 and 2004 TVREC TREATMENT Full till GT variety Non-GT variety Reduced till GT variety Non-GT variety 497 491 425 417 530 585 130 50 599 851 294 367 510 437 357 344 536 355 125 56 645 789 321 483 2003 2004 2003 EVSRC 2004 2003 WREC 2004 (TVREC) and $68.08 (EVSRC and WREC). A general production cost of $300 per acre was used for all systems and locations, and individual costs for varieties and weed management costs specific to those varieties were added for calculation of net returns. Late-season weed control was good to excellent for all cropping and weed management systems at all locations in both years. Lint quality was acceptable in all trials excepting the 2004 trial at EVSRC, where high micronaire caused deductions. Lint yields ranged from 637 to 1,806 pounds per acre during the course of the study, and net returns varied from $50 to $851 per acre. Hurricane Ivan caused significant yield loss at EVSRC in 2004, resulting in lower net returns. Average net returns for both full-till and reduced-till systems averaged over varieties, and locations were slightly better for reduced tillage ($436 vs. $414). Average net returns were similar for varieties within full-till systems ($416 for GT vs. $411 for non-GT). Average net returns favored non-GT varieties in reduced tillage ($460 vs. $412). At the TVREC, both varieties provided similar yield and net returns under reduced tillage in 2003. The GT variety in full tillage produced yield and net return comparable to reduced tillage, with the non-GT variety in full tillage producing slightly lower yield and net returns. Reduced-tillage systems provided numerically higher yields and net returns in 2004. There was no difference between yield and net return for either variety within a tillage system. No deductions were observed for lint quality at Belle Mina for either variety or tillage system. The non-GT variety provided a slight premium for strength at Belle Mina. Yield data at EVSRC showed a similar pattern as the data at Belle Mina for 2003. Yield and net returns were similar for both varieties in reduced tillage and the GT variety in full tillage. The non-GT variety in full tillage produced lower yield and net returns in 2003. Hurricane damage at Shorter in 2004 resulted in significantly lower yields and net returns for all systems and varieties. However, the GT variety in both tillage systems produced higher yields and net returns in 2004 than the non-GT variety. Significant deductions for high micronaire were seen for both varieties in 2004. This data is likely due to wind damage blowing the higherquality lint from the non-GT variety. The non-GT variety produced higher yield and net returns than the GT variety in both tillage systems at the WREC in 2003 and 2004. No deductions for lint quality were observed for either variety or tillage system either year. 36 ALABAMA AGRICULTURAL EXPERIMENT STATION EFFECT OF TIMING OF DEFOLIATION ON COTTON QUALITY C.H. Burmester, C.D. Monks, and D.P. Delaney Cotton micronaire (thickness of the cotton fiber) is one of the measurements used to gauge cotton quality. The standard for this measurement is a reading between 3.5 and 4.9. In recent years, 30 to 40 percent of Alabama's cotton crop had micronaire grades above 4.9, resulting in discounts to the farmers. The Hal-Lewis method of determining the micronaire of early-season bolls and adjusting defoliation timing is being used in some areas of the United States to reduce the amount of cotton bales with high micronaire values. Evaluation of the Hal-Lewis method was conducted under Alabama conditions in 2004. Research on its effect on all cotton quality factors and total cotton yield is needed before being used in Alabama cotton fields. In 2004, as cotton began opening, seed cotton samples were collected by hand from more than 90 grower fields in northern Alabama. These samples were ginned and, after micronaire was measured, the Hal-Lewis method was used to predict final cotton Table 1. Projected Micronaire for Farmers' Cotton Fields Using the Hal-Lewis Method Compared to Final Classing Results in Alabama, 2004 VARIETY DP 444 BG/RR DP 444 BG/RR DP 451 BG/RR DP 451 BG/RR DP 555 BG/RR DP 555 BG/RR ST 4892 BR ST 4892 BR DPLX 01W93BR DPLX 01W93BR FM 960 BR FM 960 BR ST 5599 BR ST 5599 BR DP 449 BG/RR DP 449 BG/RR PM 1218 BG/RR PM 1218 BG/RR ST 5242 BR ST 5242 BR DP 488 BG/RR DP 488 BG/RR DP 432 R DP 432 R DP 424 BG2/RR DP 424 BG2/RR ST 4646 B2R ST 4646 B2R MICRONAIRE Projected Mic. Final Mic. Projected Mic. Final Mic. Projected Mic. Final Mic. Projected Mic. Final Mic. Projected Mic. Final Mic. Projected Mic. Final Mic. Projected Mic. Final Mic. Projected Mic. Final Mic. Projected Mic. Final Mic. Projected Mic. Final Mic. Projected Mic. Final Mic. Projected Mic. Final Mic. Projected Mic. Final Mic. Projected Mic. Final Mic. 3.40 3.30 3.30 3.80 4.10 4.20 3.80 3.60 3.40 3.70 4.10 4.00 3.70 3.70 3.50 3.70 3.90 4.10 4.10 3.90 4.10 3.90 3.40 3.80 3.70 3.90 3.90 3.90 3.40 3.30 3.40 3.90 3.90 4.00 3.80 4.10 4.10 3.90 3.70 4.30 4.00 4.00 4.10 3.90 4.60 4.40 4.20 4.50 4.50 4.30 3.90 4.30 4.20 4.30 4.40 4.10 READINGS 3.60 3.90 4.20 4.00 4.30 4.30 3.70 4.40 3.60 4.10 3.70 4.00 3.70 4.20 3.70 4.10 4.10 4.70 4.30 4.00 4.00 3.90 3.40 3.70 4.00 4.10 3.90 3.90 4.10 4.70 3.70 3.50 3.50 4.00 4.00 4.50 4.60 4.30 4.10 3.90 4.10 4.40 4.40 4.20 3.90 4.20 4.20 4.40 3.80 4.70 3.70 3.80 3.90 4.60 4.10 4.70 4.00 4.40 3.90 4.50 3.60 4.10 4.00 4.10 3.70 3.70 AVERAGE DIFFERENCE MIC 3.56 3.63 3.68 3.96 4.08 4.25 3.94 4.22 3.80 3.98 3.90 4.26 3.98 4.16 3.84 4.06 4.20 4.40 4.20 4.13 4.18 4.20 3.57 3.93 3.97 4.10 4.07 3.96 0.11 -0.13 -0.26 -0.02 0.07 -0.20 -0.22 -0.18 -0.36 -0.18 -0.28 -0.17 -0.28 -0.07 2004 COTTON RESEARCH REPORT micronaire in each field. After harvest, the predicted values were compared to final classing office results. The effect of defoliation timing on micronaire, yield, and all other cotton quality factors was researched in two small-plot replicated trials. These trials were located at the Tennessee Valley Research and Extension Center (TVREC) and E.V. Smith Research Center (EVSRC) in north and central Alabama, respectively. These tests also evaluated the use of a boll opening product during each defoliation timing. Evaluation of the Hal-Lewis method indicated that it did accurately predict that cotton micronaire values would be much lower in 2004 than previous years. It also accurately predicted that one cotton variety (DP 444BG/RR) would have much lower micronaire than the other varieties tested. Based on this data we advised farmers to delay defoliation as long as possible on DP 444 BG/RR to avoid a possible grade reduction for low micronaire. At harvest, farmer field micronaire grades were approximately 0.2 points higher than estimated by the HalLewis method. This was probably due to the much warmer-than-normal September that allowed cotton to continue adding thickness to the upper bolls on the cotton plant. In the small-plot replicated tests, very early defoliation resulted in lower yields at both the TVREC and the EVSRC sites. Both sites matured a large crop in the top of the cotton plant in 2004 and required at least 50 to 60 percent open bolls before defoliation. Cotton quality at the EVSRC site determined that micronaire was lowered by the addition of a boll opener at defoliation. Staple length was reduced by the very early defoliation treatments, but strength values were slightly increased. Other quality factors were not affected by the defoliation treatments. From data collected in 2003 and 2004, it appears the Hal-Lewis method may be very useful in determining possible cotton micronaire problems. In both seasons it accurately predicted lower-than-normal micronaire values. It also accu- 37 Table 2. Effect of Defoliation Timing on Cotton Yields, TVREC, 2004 TIMING 33% no opener 33% with opener 53% no opener 53% with opener 65% no opener 65% with opener 70% no opener 70% with opener LINT YIELD (lb/a)* 1,145 b 1,200 ab 1,259 ab 1,248 ab 1,224 ab 1,310 a 1,224 ab 1,231 ab *Means followed by the same letter do not significantly differ (P=.10 DNMRT) Table 3. Effect of Defoliation Timing on Cotton Yield, Staple, and Strength, EVSRC, 2004 TIMING 24% open 35% open 69% open 81% open LSD (0.05) LINT YIELD (lb/a) 851 806 923 927 70 STAPLE 34.0 34.0 34.7 33.3 0.7 STRENGTH g/tex 30.1 30.4 28.7 28.8 1.0 rately predicted that certain varieties should be defoliated later than normal to avoid low-micronaire discounts. The data have shown that cotton defoliation is a balancing act between yield and quality. Early defoliation can result in much lower cotton yields and should be done with extreme caution. The Hal-Lewis method provides one more tool for Alabama cotton farmers to make better cotton management decisions. 38 ALABAMA AGRICULTURAL EXPERIMENT STATION NEMATICIDES EVALUATION OF TEMIK 15G AND NEW EXPERIMENTAL COMPOUNDS FOR ROOT-KNOT NEMATODE MANAGEMENT IN COTTON IN CENTRAL ALABAMA, 2004 K.S. Lawrence and S.R. Usery Temik 15G and two numbered compounds were evaluated for the management of the reniform nematode (Meloidogyne incognita) in a naturally infested field at the E.V. Smith Research Center near Shorter, Alabama. The field had a history of root-knot nematode infestation, and the soil type was a sandy loam. Temik 15G and the experimentals were applied at planting on April 28 in the seed furrow with chemical granular applicators attached to the planter. Sidedress applications of Temik 15G and KC 791230 were made at the pinhead square growth stage. Terraclor Super X 18.8G (5.5 pounds per acre) was applied at planting to all treatments. Plots consisted of two rows, 25 feet long, with a 36-inch-wide row spacing, and were arranged in a randomized complete block design with six replications. Blocks were separated by a 20-foot alley. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production practices as recommended by the Alabama Cooperative Extension System. Population densities of the root-knot nematode were determined at three time intervals throughout the season. Ten soil cores, one inch in diameter and eight inches deep, were collected from the two center rows of each plot in a systematic sampling pattern. Nematodes were extracted using the gravity sieving and sucrose centrifugation technique. Plots were harvested September 14. Data were statistically analyzed by GLM and means compared using Fisher’s protected least-significant-difference test (P<0.05). Root-knot nematode disease pressure was moderate in 2004. Pre-plant populations of root-knot nematodes averaged 25 juveniles per 150 cubic centimeters (cm3) Effect of Two Experimental Compounds on Root-knot Nematode Populations and Seed Cotton Yield SEED COTTON (lb/A) SEED COTTON NEMATICIDE RATE APPLICATION MELOIDOGYNE 30 DAP* INCOGNITA/150 CM3 OF SOIL OVER CONTROL 60 DAP 639.5 218.9 115.9 223.2 128.8 201.7 201.5 148 DAP 1,016 454.9 240.3 622.3 746.8 446.3 845.9 SEASON TOTAL Control Temik 15G KC 03RCC002P053 KC 791230 KC 03RCC002P053 + Temik 15 G KC 03RCC002P053 + KC 791230 LSD (P=0.05) *DAP = Days after planting. ---5 lb/A 5 lb/A 5 lb/A 5 + 5 lb/A 5 + 5 lb/A 77.3 plant plant plant plant + PHS plant + PHS 300.4 115.9 107.3 94.4 90.1 55.8 62.7 3,077.4 787 462 939 964 702 3,311.4 3,331.5 3,287.2 3,892.2 3,682.4 1,267.3 234 254 209 814 605 2004 COTTON RESEARCH REPORT of soil and increased to more than 700 nematodes per 150 cm3 of soil throughout the season. No differences in root-knot nematode populations (P=0.05) were observed through out the season; however, all nematicide treatments reduced root-knot numbers numerically 39 compared to the control. Cotton seed yields were numerically increased an average of 315 pounds per acre in all nematicide treatments as compared to the control. The sidedress application at PHS increase yield by an average of 709 pounds per acre. EVALUATION OF RECOMMENDED AND EXPERIMENTAL COMPOUNDS FOR RENIFORM NEMATODE MANAGEMENT IN COTTON IN NORTH ALABAMA, 2004 K.S. Lawrence, S.R. Usery, and C.H. Burmester Vydate C-LV, Temik 15G, and N-Hibit were evaluated for the management of the reniform nematode (Rotylenchulus reniformis) in a naturally infested field adjacent to the Tennessee Valley Research and Extension Center in Belle Mina, Alabama. The field had a history of reniform nematode infestation, and the soil type was a silty clay loam. Vydate C-LV was applied as a broadcast foliar spray at the fifth true-leaf stage on June 5 with an air-charged modified plot sprayer delivering 10 gallons per acre through four 8003 flat-fan nozzles at 40 psi. All rows not treated with Vydate C-LV received a foliar spray of Orthene 90S at 0.3 pounds per acre. Temik 15G (5.0 pounds per acre) was applied at planting April 29 in the seed furrow with chemical granular applicators attached to the planter. N-Hibit was applied to the seed before planting. Terraclor Super X 18.8G (5.5 pounds per acre) was applied at planting to all treatments. Plots consisted of two rows, 25 feet long, with a 40inch-wide row spacing and were arranged in a randomized complete block design with five replications. Blocks were separated by a 15-foot alley. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production practices as recommended by the Alabama Cooperative Extension System. Population densities of the reniform nematode were determined at four time intervals throughout the season. Ten soil cores, one inch in diameter and eight inches deep, were collected from the two center rows of each plot in a systematic sampling pattern. Nematodes were extracted using the gravity sieving and sucrose centrifugation technique. Plots were harvested October 5. Data were statistically analyzed by GLM and means compared using Fisher’s protected least-significant-difference test (P = 0.05). Reniform nematode disease pressure was low in 2004. Pre-plant populations of reniform nematodes averaged 167 nematodes per 150 cubic centimeters (cm3) of soil and increased to more than 800 nematodes per 150 cm3 of soil throughout the season (see table). No differences in reniform nematode populations were observed throughout the season; however, Vydate CLV numbers were numerically lower after compared to Temik 15G, N-Hibit, and Cruiser at 96 and 154 days after planting. Cotton seed yields were numerically increased an average of 175 pounds per acre in all nematicide treatments as compared to the control. Effect of Vydate, Temik 15G, and N-Hibit on Reniform Levels and Seed Cotton Yields NEMATICIDE RATE APPLICATION TIMING ROTYLENCHULUS 30 DAP* 62 DAP 355.4 355.4 479 494.4 589.8 RENIFORMIS /150 CM3 SOIL SEED COTTON (LB/A) SEASON TOTAL SEED COTTON OVER CONTROL 96 DAP 705.6 602.6 803.4 803.4 535.9 154 DAP 504.7 386.3 618 556.2 437.9 Cruiser Vydate C-LV Temik 15G N-Hibit LSD (P = 0.05) ---17oz 5 lb/A 3oz/cwt ---4th leaf at plant at plant 257.5 252.4 370.8 375.9 189.2 1,821 1,595 2,270 2,228 1,225 3,997.9 4,128.6 4,215.3 4,175.6 450.9 130.7 217.4 177.7 *DAP = Days after planting 40 ALABAMA AGRICULTURAL EXPERIMENT STATION EVALUATION OF TELONE II, VAPAM HL, AND TEMIK 15G FOR RENIFORM NEMATODE MANAGEMENT IN COTTON IN NORTH ALABAMA, 2004 K.S. Lawrence, S.R. Usery, C.H. Burmester, and G.W. Lawrence Telone II, Vapam HL, and Temik 15G were evaluated for the management of the reniform nematode (Rotylenchulus reniformis) in a naturally infested field adjacent to the Tennessee Valley Research and Extension Center in Belle Mina, Alabama. The field had a history of reniform nematode infestation, and the soil type was a silty clay loam. Liquid fumigants were applied with a modified John Deere ripper hipper. A CO2-charged system was used to propel the fumigants through flow regulators mounted on stainless steel delivery tubes attached to the trailing edge of forward-swept chisels. The fumigants were injected 18 inches deep 21 days prior to planting with one chisel per row. Rows were immediately hipped with disk hillers to seal and prevent rapid loss of the fumigant. Temik 15G was applied at planting with granular chemical applicators attached to the planter. Di-syston 8EC was included as an insecticide-treated control. All plots were treated with Orthene 75S at four ounces per acre when thrips were detected in any plots. Terraclor Super X 18.8G (5.5 pounds per acre) was applied at planting to all treatments. Plots consisted of four rows, 25 feet long, with a 40-inch-wide row spacing and were arranged in a randomized complete block design with five replications. Blocks were separated by a 15-foot alley. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production practices as recommended by the Alabama Cooperative Extension System. Population densities of the reniform nematode were determined at four time intervals throughout the season. Ten soil cores, one inch in diameter and eight inches deep, were collected from the two center rows of each plot in a systematic sampling pattern. Nematodes were extracted using the gravity sieving and sucrose centrifugation technique. Plots were harvested October 5. Data were statistically analyzed by GLM and means compared using Fisher’s protected least-significant-difference test (P>0.05). Reniform nematode disease pressure was low in 2004. Pre-plant populations of reniform nematodes averaged 180 nematodes per 150 cubic centimeters (cm3) of soil and increased to more than 2,200 nematodes per 150 cm3 of soil by harvest (see the table). No differences in reniform nematode populations were observed at 30, 62, and 96 days after planting. At harvest, reniform populations were lower (P=0.05) in the Telone II three gallon per acre plots as compared to the Temik 15G plots. Seed cotton yields were greater in the Telone II plots as compare to the control (P=0.05). However, cotton seed yields were numerically increased an average of 222 pounds per acre in all nematicide treatments as compared to the control. Effect of Vapam, Temik 15 G, and Telone II on Reniform Nematode Levels and Seed Cotton Yields APPLICATION TIMING SEED ROTYLENCHULUS 30 DAP* 62 DAP 1,118 1,112 1,483 1,360 1,375 1,488 191 RENIFORMIS/150 CM3 OF SOIL COTTON SEED COTTON OVER CONTROL NEMATICIDE RATE (LB/A) 96 DAP 1,133 834 711 1,282 1,174 587 974 154 DAP 1,607ab 1,900 ab 1,885 ab 2,209 a 1,561 ab 881 b 837 SEASON TOTAL Control Vapam HL Vapam HL Temik 15G Telone II Telone II LSD (P<0.05) ---3 GPA 5 GPA 5.0 lb/A 1.5 GPA 3 GPA ---14 DBP 14 DBP at plant 14 DBP 14 DBP 227 67 149 129 72 165 3,858 3,913 4,228 4,980 4,182 3,121 1,180 4,273 b 4,334 ab 4502 ab 4,416 ab 4,569 ab 4,657 a 61 229 143 296 384 362.3 *DAP = Days after planting 2004 COTTON RESEARCH REPORT 41 EVALUATION OF SEED TREATMENT NEMATICIDES FOR RENIFORM NEMATODE MANAGEMENT IN COTTON IN NORTH ALABAMA, 2004 K.S. Lawrence, S.R. Usery, C.H. Burmester, and G.W. Lawrence The field used for this study had a history of reniform nematode infestation, and the soil type was a silty clay loam. All seed treatments were applied by the manufacturer. Temik 15G (5.0 and 7.0 pounds per acre) was applied at planting on April 29 in the seed furrow with chemical granular applicators attached to the planter. Terraclor Super X 18.8G (5.5 pounds per acre) was applied at planting to all treatments. Plots consisted of two rows, 25 feet long, with a 40-inch-wide row spacing and were arranged in a randomized complete block design with five replications. Blocks were separated by a 15-foot alley. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production practices as recommended by the Alabama Cooperative Extension System. Population densities of the reniform nematode were determined at four time intervals throughout the season. Ten soil cores, one inch in diameter and eight inches deep, were collected from the two center rows of each plot in a systematic sampling pattern. Nematodes were extracted using the gravity sieving and sucrose centrifugation technique. Plots were harvested October 5. Data were statistically analyzed by GLM and means compared using Fisher’s protected least-significant-difference test (P=0.05). Reniform nematode disease pressure was low in 2004. Preplant populations of reniform nematodes averaged 150 nematodes per 150 cubic centimeters (cm3) of soil and increased to more than 700 nematodes per150 cm3 of soil by harvest. No differences in reniform nematode populations (P=0.05) due to nematicide treatment were observed at 30, 62, 96, or 154 days after planting (DAP) (see table), although reniform population season totals were numerically lower in the A14006-B experimental at the higher rate of 15.0 milligrams per 100 kilograms of seed compared to Temik 15G at seven Efficacy of Experimental Seed Treatments on Reniform Nematode Populations and Seed Cotton Yield RATE 100 KG SEED SEED ROTYLENCHULUS RENIFORMIS/150 CM3 SOIL NEMATICIDE SEED COTTON (LB/A) SEASON TOTAL COTTON OVER STANDARD 30 DAP* Dynasty 1.04 FS + Cruiser 5 FS A14006-B + Dynasty 1.04 FS + Cruiser 5FS A14006-B + Dynasty 1.04 FS +Cruiser 5 FS Dynasty 1.04 FS + Temik 15G Dynasty 1.04 FS + Temik 15G A14006-B + Dynasty 1.04 FS +Cruiser 5 FS + Temik 15G LSD (P<0.05) *DAP = Days after planting 62 DAP 96 DAP 154 DAP 25.0 g + 34.0 mg 25.0g + 34.0 mg + 12.0 mg 25.0 g + 34.0 mg + 15.0 mg 25.0 g + 5 lb/A 422.3 535.6 654.1 433 2,044 3,753.7 ab 231.8 231.8 726.2 695 1,883 4,030.3 ab 277 509.9 324.5 350.2 711 1,895 3,747.4 a 283 309 247.2 540.8 386 1,482 3,914.7 ab 161 25.0 g + 7 lb/A 25.0 g + 34.0 mg + 15.0 mg + 5 lb/A 278.1 61.8 355.4 325 1,020 4,026.1 b 273 293.6 345.2 211.2 463 448.1 378.4 572 376 1,524 4,013.5 ab 468.8 260 42 pounds per acre. Seed cotton yields in the nematicide treatments were not greater than the control (P=0.05); however, cotton seed yields were numerically increased an average of 250 pounds per acre in all nematicide treatments as compared to the control. The experimental A14006-B averaged over both rates numerically increase yield 119 pounds per acre as compared to Temik 15G at five pounds per acre. ALABAMA AGRICULTURAL EXPERIMENT STATION 2004 COTTON RESEARCH REPORT 43 FUNGICIDES EVALUATION OF SELECTED FUNGICIDE SEED TREATMENTS FOR MANAGEMENT OF COTTON SEEDLING DISEASE IN CENTRAL ALABAMA, 2004 K.S. Lawrence, S.R. Usery, and D.P. Moore This cotton fungicide test was planted April 12 at the Prattville Agricultural Research Unit in Prattville, Alabama. The objectives of this trial were to evaluate Dynasty CST, Systhane 40 WSP, Allegiance FL, RTUBaytan-Thiram 1.76 FS, Ascend 30 2.64 EC, Baytan 30, Delta Coat AD 3.24 FS, and Protege FL1.9 LS in various combinations and rates for management seedling disease of cotton under high- and low-disease-pressure regimes. The field had a history of cotton seedling disease, and the soil type was a sandy loam (62.5, 22.5, 15; S-S-C, pH 6.5). Soil was 65oF at a four-inch depth at 10 a. m. with adequate moisture at planting. All seed treatment fungicides were applied by the manufacturer. Plots consisted of two rows, 30 feet long, with a 36-inch-wide row spacing and were arranged in a randomized complete block design with six replications. High-disease- Efficacy of Selected Fungicide Seed Treatments on Cotton Stand, Uniformity, and Yield TREATMENT RATE 100 KG SEED STAND PER HIGH DISEASE PRESSURE 25-FT ROW 21 DAP* Check Dynasty CST 125FS Dynasty CST 125FS + Systhane 40 WSP Allegiance FL 318 SC + RTU-Baytan-Thiram 1.76FS Ascend 30 2.64EC + Allegiance FL + Baytan 30 Allegiance FL + RTU Baytan Thiram 1.76FS + Delta Coat AD 3.24 FS Allegiance LS + RTU-Baytan-Thiram 1.76FS + Protege FL1.9 LS + Allegiance LS Allegiance LS + RTU-Baytan-Thiram 1.76FS + A13012 125FS Allegiance LS + RTU-Baytan-Thiram 1.76FS + A13012 125FS + Systhane 40 WSP Allegiance LS + RTU-Baytan-Thiram 1.76 FS + A13012 125FS 32 g 32 + 21 g 15 + 41 g 19 + 15 + 10 g 15 + 41 + 300 g 15 + 41+ 8 + 15 g 15 + 41 + 32 g 15+ 41 + 32 +21 g 15 + 41 + 1.35 g 34 e 68.3 abc 74.8 ab 55.5 cd 65.8 abc 75.1 ab 80.3 a 71.5 abc 69.8 abc 67.8 abc 61.5 bc 18.0 42 DAP 39 c 62 ab 63.5ab 45.7 bc 63.8 a 68.3 a 62.8 ab 56.3 abc 50.8 abc 61.5 ab 56.5 abc 5 SKIP INDEX 42 DAP 18.7 a 10.8 bc 13.3bc 15.7 ab 8.8 c 9.0 c 11.5 bc 13.7 abc 15.1 ab 13.5 abc 12.3 bc 137.8 SEED COTTON LB/A 1,290.7 ab 1,411.7 a 1,403.6 a 1,242.3 b 1,331 ab 1,302.8 ab 1,306.8 ab 1,326.9 ab 1,391.5 a 1,318.9 ab 1,359.2 ab Allegiance LS + RTU-Baytan-Thiram 1.76 FS 15 + 41 + 1.35 g + A13012 125FS + Terraclor 10 GR + 2,500g/ac LSD (P< 0.05) 17.6 44 ALABAMA AGRICULTURAL EXPERIMENT STATION Efficacy of Selected Fungicide Seed Treatments on Cotton Stand, Uniformity, and Yield TREATMENT RATE 100 KG SEED STAND PER LOW DISEASE PRESSURE 25-FT ROW 21 DAP* Check Dynasty CST 125FS Dynasty CST 125FS + Systhane 40 WSP Allegiance FL 318 SC + RTU-Baytan-Thiram 1.76FS Ascend 30 2.64EC + Allegiance FL + Baytan 30 Allegiance FL + RTU Baytan Thiram 1.76FS + Delta Coat AD 3.24 FS Allegiance LS + RTU-Baytan-Thiram 1.76FS + Protege FL1.9 LS + Allegiance LS Allegiance LS + RTU-Baytan-Thiram 1.76FS + A13012 125FS Allegiance LS + RTU-Baytan-Thiram 1.76FS + A13012 125FS + Systhane 40 WSP Allegiance LS + RTU-Baytan-Thiram 1.76 FS + A13012 125FS 32 g 32 + 21 g 15 + 41 g 19 + 15 + 10 g 15 + 41 + 300 g 15 + 41+ 8 + 15 g 15 + 41 + 32 g 15+ 41 + 32 +21 g 15 + 41 + 1.35 g 59.5 c 71.1 abc 78.6 a 76.6 ab 75.5 ab 75.8 ab 62.1 abc 72.5 abc 69.5 abc 73.5 abc 79.1 a 15.1 42 DAP 57.5 b 71.7 a 69,2 ab 72.0 a 68.2 ab 70.2 a 67.8 ab 71.2 a 68.3 ab 74.2 a 73.2 a 11.8 SKIP INDEX 42 DAP 8.7 ab 7.6 abc 5.3 bc 7.3 abc 8.8 c 9.0 c 6.5 abc 8.0 abc 6.6 abc 6.6 abc 6.5 abc 3.4 SEED COTTON LB/A 1,391.5 d 1,577.0 abc 1,528.6 a-d 1,456.0 cd 1,532.6 a-d 1,629.4 ab 1,673.8 a 1,645.6 a 1,633/5 ab 1,597.2 abc 1,528.6 a-d 161.4 Allegiance LS + RTU-Baytan-Thiram 1.76 FS 15 + 41 + 1.35 g + A13012 125FS + Terraclor 10 GR + 2,500g/ac LSD (P< 0.05) incidence plots were infested with millet seed inoculated with Pythium ultimum and Rhizoctonia solani. Blocks were separated by a 20-foot alley. The nematicide Temik 15G (5.0 pounds per acre) was applied in-furrow at planting. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production practices as recommended by the Alabama Cooperative Extension System. Stand counts and skip index ratings were recorded at three and six weeks after planting to determine the percent seedling loss and stand density due to cotton seedling disease. Plots were harvested October 18. Data were statistically analyzed by GLM and means compared using Fisher’s protected least-significant-difference test (P=0.05). The 2004 season began with optimum environmental conditions but ended with repeated hurricanes. The environmental conditions for 10 days after planting (DAP) included average soil and air temperature maximums and minimums of 70, 45, 66.7, and 62o F and 0.75 inches of precipitation accumulated. Seedling dis- ease incidence was severe in the inoculated plots and moderate in the non-inoculated plots. At 14 DAP under high disease pressure, all seed treatments increased plant stand as compared to the untreated control. However, by 28 DAP, Dynasty CST alone or with Systhane, Ascend 30 + Allegiance FL + Baytan 30, Allegiance LS + RTU-Baytan-Thiram alone or overcoated with Delta Coat AD, Protege FL, or A13012 125FS increased seedling stand over the control. These treatments also improved stand uniformity as indicated by the skip index. Dynasty CST alone or with Systhane and Allegiance LS + RTU-Baytan-Thiram + A13012 + Systhane produced significantly greater yields than the standard Allegiance FL 318 SC + RTU-Baytan-Thiram seed treatment. In the non-inoculated or low-disease-pressure plots, Dynasty CST, Allegiance FL + RTU Baytan Thiram alone or with an over-treatment of Delta Coat AD, or A13012, or followed by an in-furrow application of A13012 125FS or Terraclor 10G improved seedling stand at 28 DAP as compared to the control. Allegiance 2004 COTTON RESEARCH REPORT FL + RTU Baytan Thiram followed by Terraclor 10G in furrow improved stand uniformity as compared to the control. Seed cotton yields were increased over the control by Dyansty CST alone or with Systhane and 45 Allegiance LS + RTU-Baytan-Thiram with an over-coat of Delta Coat AD, or Protege FL, or A13012, or A13012 + Systhane, or followed by an in-furrow application of A13012. EVALUATION OF SELECTED FUNGICIDES FOR MANAGEMENT OF COTTON SEEDLING DISEASE IN THE TENNESSEE VALLEY REGION OF ALABAMA, 2004 K.S. Lawrence, S.R. Usery, and B.E. Norris This cotton fungicide test was planted April 16 at the Tennessee Valley Research and Extension Center in Belle Mina, Alabama. The objectives of this trial were to evaluate Dynasty CST, Reason, Rovral CF, Ridomil Gold, and Quadris in various combinations for management of seedling disease of cotton under high and low disease-pressure regimes. The field had a history of cotton seedling disease, and the soil type was a Decatur silty loam. Soil was 65o F at four inches depth at 10 a.m. with adequate moisture at planting. Fungicides were applied either as a seed treatment by the manufacturer or as an in-furrow spray application at planting. All in-furrow fungicide sprays were applied with flat-tip 8002E nozzles calibrated to deliver six gallons per acre at 18 pounds per square inch (psi). Plots consisted of two rows, 25 feet long, with a 40-inch-wide row spacing and were arranged in a randomized complete block design with five replications. High-disease-incidence plots were infested with millet seed inoculated with Pythium ultimum. Blocks were separated by a 20-foot alley. The nematicide Temik 15G (5.0 pounds per acre) was applied in-furrow at planting. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production practices as recommended by the Alabama Cooperative Extension System. Stand counts and skip index ratings were recorded at two and four weeks after planting to determine the percent seedling loss and stand density due to cotton seedling disease. Plots were harvested September 23. Data were statistically analyzed by GLM and means compared using Fisher’s protected least-significant-difference test (P<0.05). The 2004 season began with optimum environmental conditions but ended with repeated hurricanes. The environmental conditions for 10 days after planting (DAP) included average soil and air temperature maximums and minimums of 64.7, 58, 79.5, and 53.8 oF and 0.06 inches Effect of Reason, Rovral, Ridomil Gold,and Quadris In-furrow Fungicide Combinations as Compared to Dynasty Seed Treatments for Cotton Stand, Uniformity, and Yield TREATMENT RATE STAND PER LOW DISEASE PRESSURE 25-FT ROW 14 DAP* Control Dynasty CST 125 FS Reason + Rovral CF Ridomil Gold + Rovral CF Quadris + Ridomil Gold LSD (P<0.05) *DAP = Days after planting 28 DAP 51.4 c 67.8 a 69.0 a 55.4 bc 62.6 ab 8.4 SKIP INDEX 42 DAP 3.6 2.8 1.6 2.6 2.2 3.4 SEED COTTON (LB/A) 4,135.3 4,142.7 4,147.9 4,138.0 4,017.2 309.2 51 32 g/100 kg seed 0.5 + 0.5 oz/1,000 row ft 0.15 + 0.5 oz/1,000 row ft 6.0 + 0.5 oz/1,000 row ft 55.6 43.0 47.6 34.8 20.9 46 of precipitation accumulated. Seedling disease incidence was moderate. At 14 DAP, none of the fungicide treatments increased plant stand (P<0.05) as compared to the nontreated control. However, by 28 DAP, Dynasty CST, Reason + Rovral CF, and Quadris + Ridoml Gold ALABAMA AGRICULTURAL EXPERIMENT STATION increased seedling stand (P<0.05) over the control. The skip index indicating an evenly spaced seedling stand was similar between all of the treatments. No differences in seed cotton yields were observed between the fungicide treatments and the nontreated control. EVALUATION OF SELECTED FUNGICIDE SEED TREATMENTS FOR MANAGEMENT OF COTTON SEEDLING DISEASE IN THE TENNESSEE VALLEY REGION OF ALABAMA, 2004 K.S. Lawrence, S.R. Usery, and B.E. Norris This cotton fungicide test was planted April 16 at the Tennessee Valley Research and Extension Center in Belle Mina, Alabama. The objectives of this trial were to evaluate Dynasty CST, Systhane 40 WSP, Allegiance FL, RTU-Baytan-Thiram 1.76 FS, Ascend 30 2.64 EC, Baytan 30, Delta Coat AD 3.24 FS, and Protege FL1.9 LS in various combinations and rates for management of seedling disease of cotton under high and low disease-pressure regimes. The field had a history of cotton seedling disease, and the soil type was a Decatur silty loam. Soil was 65o F at four inches in depth at 10 a.m. with adequate moisture at planting. All seed treatment Efficacy of Selected Fungicide Seed Treatments on Cotton Stand, Uniformity, and Yield TREATMENT RATE 100 KG SEED STAND PER HIGH DISEASE PRESSURE 25-FT ROW 21 DAP* Control Dynasty CST 125 FS Dynasty CST 125 FS + Systhane 40 WSP Allegiance FL + RTU-Baytan-Thiram 1.76 FS Ascend 30 2.64 EC + Allegiance FL + Baytan 30 Allegiance FL + RTU Baytan Thiram 1.76 FS + Delta Coat AD 3.24 FS Allegiance LS + RTU-Baytan-Thiram 1.76 FS + Protege FL1.9 LS + Allegiance LS Allegiance LS + RTU-Baytan-Thiram 1.76 FS + A13012 Allegiance LS + RTU-Baytan-Thiram 1.76 FS + A13012 + Systhane 40 WSP Allegiance LS + RTU-Baytan-Thiram 1.76 FS + A13012 Allegiance LS + RTU-Baytan-Thiram 1.76 FS + A13012 + Terraclor 10 GR LSD (P<0.05) 32 g 32 + 21 g 15 + 41 g 19 + 15 + 10 g 15 + 41 + 300 g 15 + 41+ 8 + 15 g 15 + 41 + 32 g 15 + 41 + 32 + 21 g 15 + 41 + 1.35 g 15 + 41 + 1.35 g 2,500 g/ac 10.8 cd 26.2 bc 40.6 ab 25.8 bc 27.6 b 30.6 ab 44.0 a 38.0 ab 32.0 ab 38.0 ab 35.8 ab 16.335 42 DAP 6.4 c 38.4 b 54.6 a 32.2 b 33.4 b 57 a 49.6 a SKIP INDEX 42 DAP 19.6 a 5 bcd 5 bcd 7 bc 8b 5.2 bcd 4.4 bcd 51.6 a SEED COTTON (LB/A) 1,709.6 e 3,661.7 abcd 3,786.1 abc 3,447.9 cd 3,506.9 bcd 3,833.2 ab 2.8 d 3,860.4 a 3,478.2 cd 8.4 b 338.3 59.2 a 34.4 b 3.2 cd 7.8 b 32.6 b 10.325 4.158 2004 COTTON RESEARCH REPORT fungicides were applied by the manufacturer. Plots consisted of two rows, 25 feet long, with a 40-inch-wide row spacing and were arranged in a randomized complete block design with five replications. High-diseaseincidence plots were infested with millet seed inoculated with Pythium ultimum and Rhizoctonia solani. Blocks were separated by a 20-foot alley. The nematicide Temik 15G (5.0 pounds per acre) was applied in-furrow at planting. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production practices as recommended by the Alabama Cooperative Extension System. Stand counts and skip index ratings were recorded at three and six weeks after planting to determine the percent seedling loss and stand density due to cotton seedling disease. Plots were harvested September 23. Data were statistically analyzed by GLM and means compared using Fisher’s protected least-significant-difference test (P=0.05). 47 The 2004 season began with optimum environmental conditions but ended with repeated hurricanes. The environmental conditions for 10 days after planting (DAP) included an average soil and air temperature maximums and minimums of 64.7, 58, 79.5, and 53.8o F and 0.06 inches of precipitation accumulated. Seedling disease incidence was severe in the inoculated plots and moderate in the non-inoculated plots. At 21 and 42 DAP under high disease pressure, all seed treatments increased plant stand (P<0.05) as compared to the untreated control. At 42 DAP, Dynasty CST with Systhane, Allegiance LS + RTU-Baytan-Thiram overcoated with Delta Coat AD, Protege FL, and A13012 125FS increased seedling stand (P<0.05) over the Dynasty CST alone and the Allegiance FL + RTU Baytan Thiram alone. A lower skip index (P<0.05) indicating an evenly spaced seedling stand was observed in all the seed treatments. Seed cotton yield was also increased by all fungicides as compared to the Efficacy of Selected Fungicide Seed Treatments on Cotton Stand, Uniformity, and Yield TREATMENT RATE 100 KG SEED STAND PER LOW DISEASE PRESSURE 25-FT ROW 21 DAP* Check Dynasty CST 125 FS Dynasty CST 125 FS + Systhane 40 WSP Allegiance FL + RTU-Baytan-Thiram 1.7FS Ascend 30 2.64 EC + Allegiance FL + Baytan 30 Allegiance FL + RTU Baytan Thiram 1.76 FS + Delta Coat AD 3.24 FS Allegiance LS + RTU-Baytan-Thiram 1.76 FS + Protege FL1.9 LS + Allegiance LS Allegiance LS + RTU-Baytan-Thiram 1.76 FS + A13012 Allegiance LS + RTU-Baytan-Thiram 1.76 FS + A13012 + Systhane 40 WSP Allegiance LS + RTU-Baytan-Thiram 1.76 FS + A13012 Allegiance LS + RTU-Baytan-Thiram 1.76 FS + A13012 + Terraclor 10 GR LSD (P<0.05) *DAP = Days after planting 42 DAP 53.4 c 56.6 bc 70.2 ab 69.6 ab 69.4 b 66.2 bc 66 abc 77.6 a 71.8 a 9.2 ab 70.8 ab 15.02 SKIP INDEX 42 DAP 5 ab 1.4 b 0.8 b 0.6 b 2.6 b 3.2 b 1.6 b 0.4 b 2.8 b 1.2 b 1.4 b 4.7 SEED COTTON (LB/A) 4,112.3 4,023.5 4,146.3 4,086.7 4,141.1 4,119.7 4,138.5 4,132.2 4,087.8 4,266.6 4,157.3 250.31 39.6 abc 32 g 32 + 21 g 15 + 41 g 19 + 15 + 10 g 15 + 41 + 300 g 15 + 41+ 8 + 15 g 15 + 41 + 32 g 15 + 41 + 32 + 21 g 15 + 41 + 1.35 g 15 + 41 + 1.35 g 2,500 g/ac 47.6 abc 53.4 ab 36.6 bc 47.8 abc 30.8 c 58.6 a 45.2 abc 41.8 bc 51.2 ab 52.4 ab 20.15 48 control. Yield was increased by 2,000 pounds of seed cotton per acre as compared to the control under high disease pressure. In the non-inoculated or low disease-pressure plots, seedling stand was not increased (P<0.05) over the control at three weeks after planting. However, at six weeks ALABAMA AGRICULTURAL EXPERIMENT STATION after planting, seven of the seed treatments increased yield (P<0.05) over the nontreated control. All fungicide treatment produced a lower skip index (P<0.05) as compared to the control. Seed cotton yield was not increased as compared to the control under low disease pressure. EVALUATION OF SELECTED IN-FURROW FUNGICIDES FOR MANAGEMENT OF COTTON SEEDLING DISEASE IN CENTRAL ALABAMA, 2004 K. S. Lawrence, S. R. Usery, and D. P. Moore This cotton fungicide test was planted April 12 at the Prattville Agricultural Research Unit in Prattville, Alabama. The objectives of this trial were to evaluate Dynasty CST, Reason, Rovral CF, Ridomil Gold, and Quadris in various combinations for management of seedling disease of cotton under high-disease-pressure regimes. The field had a history of cotton seedling disease, and the soil type was a sandy loam (62.5, 22.5, 15; S-S-C, pH 6.5). Soil was 65oF at a four-inch depth at 10 a.m. with adequate moisture at planting. All seed treatment fungicides were applied by the manufacturer. Plots consisted of two rows, 30 feet long, with a 36-inch-wide row spacing and were arranged in a randomized complete block design with six replications. High disease incidence plots were infested with millet seed inoculat- ed with Pythium ultimum. Blocks were separated by a 20-foot alley. The nematicide Temik 15G (5.0 pounds per acre) was applied in-furrow at planting. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production practices as recommended by the Alabama Cooperative Extension System. Stand counts and skip index ratings were recorded at three and six weeks after planting to determine the percent seedling loss and stand density due to cotton seedling disease. Plots were harvested October 18. Data were statistically analyzed by GLM and means compared using Fisher’s protected least-significant-difference test (P<0.05). The 2004 season began with optimum environmental Effect of Reason, Rovral, Ridomil Gold, and Quadris In-furrow Fungicide Combinations as Compared to Dynasty Seed Treatments for Cotton Stand, Uniformity, and Yield TREATMENT RATE STAND PER HIGH DISEASE PRESSURE 25-FT ROW 14 DAP* Control Dynasty CST 125 FS Reason + Rovral CF Ridomil Gold + Rovral CF Quadris + Ridomil Gold LSD (P<0.05) *DAP = Days after planting 28 DAP 7 73.5 74.2 75.8 75.0 3.5 SKIP INDEX 42 DAP 1,480.2 7.7 6.5 7.0 7.3 127.3 SEED COTTON LB/A 85.5 32 g/100 kg seed 0.5 + 0.5 oz/1,000 row ft 0.15 + 0.5 oz/1,000 row ft 6.0 + 0.5 oz/1,000 row ft 17.1 74.3 81.7 88.7 80.0 78.2 12.3 1,444.0 1,403.6 1,480.2 1,512.5 2004 COTTON RESEARCH REPORT conditions but ended with repeated hurricanes. The environmental conditions for 10 days after planting (DAP) included average soil and air temperature maximums and minimums of 64.7, 58, 79.5, 53.8° F and 0.06 inches of precipitation accumulated. Seedling disease incidence was light. At 21 and 42 DAP none of the 49 fungicide treatments increased plant stand (P<0.05) as compared to the nontreated control. The skip index indicating an evenly spaced seedling stand was similar among all of the treatments. No differences in seed cotton yields were observed between the fungicide treatments and the nontreated control.