so) CX C("FTCh tr, rO YS*;" EA RC H R U 8 irr 02 c(k:r jxJ S~~ 'r (B~ 8 IR #R C H ': iT UE[(fi OL/">,' .. .. ... i~~a~s>4 'tY ' t ;x 02C ------ ------ -..l. .w. V R O T .T (.. ... -: :: -20 0 2 Z % W -lb A*OW :::::::: A D:~:~:2i: ~ : ~ : I. -t Ps- C* 4' E R T U 2 Cu I u N RES LA ,,RCH RFPOR T ii:2002 :,,':O; jTTON RESEARCH REPOR' 1% fl v RESEARCH REPORT SERIES NO.24 MARCH 2003 ALABAMA ACRICULTURA'L EXPERIMENT STATION JOHN JENSEN, INTERIM DIRECTOR AUBURN UNIVERSITY, AUBURN, ALABAMA PRINTED IN COOPERATION WITH THE ALABAMA COOPERATIVE EXTENSION SYSTEM (ALABAMA A&M UNIVERSITY AND AUBURN UNIVERSITY.) " 2OO2 CC). TON R AR P T02CTT jooc,, UoN R . ... .. 0>0 /NR C V-", gg r 1 Kji: : C H:: C F-lo i REP 44%. MO IX ~ x ~x ....~ ~b~.~. .. .t- .:)i""' ' :::. :::: 5\ :~S::\ 1 : :I t~ ~5~:5 ' '' ~.,,~.... x ~;:~X :Is~ #:": ~:~::':~:I:~:Y:~:.:i::~:I j~::~1~:I: 18~i t ::;~: : '; ' ::::' 'ii~i~iiii l''''''''iH~jiiij lijiiiii:i:1:iij:!: : : ,-::::: ::::::::i::::::i::::: :jiiiil:I...t~.:::''' fiff'i::i::t:t:~:l:t:i:#6::: Iiii i~I~fiilll iiI:I:181i:::::::I::~iii:::lil~S~~I~ I rx>V/A.:-x-xrw.Q . ACKNOWLEDGMENTS This publication is a joint contribution of Auburn University, Alabama Agricultural Experiment Stations, Alabama A&M University, and the USDA Agricultural Research Service. Research contained herein was partially funded through the Alabama Cotton Commission and private industry grants. All donations, including the Alabama Cotton Commission grants and private industry funding, are appreciated. CONFIDENTIAL REPORT Publication, display, or distribution of data contained herein should not be made without prior written approval. Mention of a trademark or product does not constitute a guarantee of the product by Auburn University and does not imply its approval to the exclusion of other products. Information contained herein is available to all persons regardless of race, color, sex, or national origin. Issued in furtherance of Cooperative Extension work in agriculture and home economics, Acts of May 8 and June 30, 1914, and other related acts, in cooperation with the U.S. Department ofAgriculture. The Alabama Cooperative Extension System (Alabama A&M University and Auburn University) offers educational programs, materials, and equal opportunity employment to all people without regard to race, color, national origin, religion, sex, age, veteran status, or disability. CONTIE NTS Editors, Contributors VARIETY TRIALS Cherokee County Cotton Variety Trial ............................................................... ............. 1 2002 M onroe County Roundup Ready Cotton Variety Trial ........................................................................................................... 1 No Till Cotton Varieties at E.V. Smith ................................................................................. 2 Variety Evaluation in Ultra Narrow Row Cotton at E.V. Smith ........................................................... 3 2002 Fusarium W ilt/Commercial Cotton Variety Test .............................................. ................................. 4 Evaluation of Early Season Cotton Varieties for Response to Boll Rot Disease in Alabama......................... ....................... 4 Evaluation of Full Season Cotton Varieties for Response to Boll Rot Disease in Alabama ................................................... 5 Transgenic Cotton Variety Response to Rotylenchulus reniformis on Cotton Following Corn in North Alabama ....................... 6 Transgenic Cotton Variety Response to Rotylenchulus reniformis on Monocultured Cotton in North Alabama ................. 7 CROP PRODUCTION Weed Population Dynamics Under Glyphosate-Resistant Cotton Cropping Systems ......................... ........................ 9 Evaluation of Subsurface Irrigation in the W iregrass ................................ ................................................ 10 Sprinkler and Subsurface Drip Irrigation at the Tennessee Valley Research and Extension Center ............................. 12 Conservation Tillage and Poultry Litter Effects on Cotton .................................................................. 16 Irrigated Cotton Management with Conservation Tillage ............................................................... 18 Nutrient Movement under Long-Term Broiler Litter Fertilization ..................................................... 19 New Changes Produce Record Yields on Old Rotation ............................... ................................. 21 INSECTICIDES Effects of a Wide Range of Insecticides on Tarnished Plant Bugs in Cotton ................................. 23 Control of Thrips on Seedling Cotton .............................. ...................................................... .... 25 Evaluation of Seed Treatments for Thrips Control in the Wiregrass Area ............................................ 26 Evaulation of New Insecticide Chemistry and Biotechnology .......................................................... 28 NEMATICIDES In-Season Control of Reniform Nematodes in Northern Alabama ......................................................... ................................... 31 Evaluation of Messenger with Temik 15G for Control of Rotylenchulus reniformis on Cotton in Central Alabama ............ 32 Impact of Fumigation with Telone and Applications of Temik on Cotton in Reniform Nematode Infested Fields near P rattville ..................................................................................................................................... ........ ............................ 33 Impact of Side Dress Temik Applications on Cotton Production in Reniform Nematode Infested Fields near Huxford .............. 34 Fall Fumigation Versus Spring Fumigation for Reniform Control in Heavily Infested Cotton Fields ............................................ 35 Effect of Summer Crops and Winter Cover Crops Rotation on Reniform Nematode Populations in Cotton ................................ 35 FUNGICIDES Evaluation of Terra Control SC 823 on Irrigated and Nonirrigated cotton............................................................................... 37 Evaluation of Planting Date for Response to Boll Rot Disease in Alabama ................................................................................ 38 Evaluation of Selected Fungicides for Control of Cotton Boll Rot Disease on Deltapine NuCotn 33B ....................................... 39 Foliar Fungicides and Fertilizers for Black Belt Cotton.. . ............................................................................................................... 40 Evaluation of Selected Seed Treatments for Management of Cotton Seedling Disease in North Alabama ................................. 41 Evaluation of Selected Seed Treatments for Management of Cotton Seedling Disease in Central Alabama ............................ 42 Evaluation of Selected In-Furrow Fungicides for Management of Cotton Seedling Disease in Central Alabama .................... 44 Evaluation of Selected In-Furrow Fungicides for Management of Rhizoctonia solani Seedling Disease in C entral A labam a .......................................... ..................... ......................................... ..... ....................... ........................ 45 Evaluation of Selected In-Furrow Fungicides for Management of Cotton Seedling Disease in North Alabama ...................... 46 Evaluation of Selected In-Furrow Fungicides for Management of Rhizoctonia solani Seedling Disease in North Alabama ...................................... ................... 48 MOLECULAR STUDIES Developing in vitro Cotton Culture Systems for Reniform Nematode Studies ........................................ 49 Isolation of Genes Related to Cotton Fiber Development ........................................................................ 49 Genetic Variation in Reniform Nematode Populations ............................................... 50 Authors' IndexAuthors' Index ................................................................................................................................................................................... 52 EDITORS Kathy S. McLean Assistant Professor Entomology and Plant Pathology Auburn University C. Dale Monks Professor and Extension Specialist Agronomy and Soils Auburn University CONTRIBUTORS James R. Akridge Superintendent Brewton Agricultural Research Unit James W. Baier Assistant Professor, Biosystems Engineering Auburn University Celeste Bell Department of Plant and Soil Science Alabama A&M University W. C. Birdsong Area Agronomist Wiregrass Research and Extension Center James Bolton Department of Plant and Soil Science Alabama A&M University Charles Burmester Extension Agronomist Tennessee Valley Research and Extension Center, Belle Mina, Alabama Larry M. Curtis Professor and Extension Specialist Biosystems Engineering, Auburn University Dedrick Davis Department of Plant and Soil Science Alabama A&M University Dennis P. Delaney Extension Specialist, Agronomy and Soils Auburn University Dewang Deng Department of Plant and Soil Science Alabama A&M University David Derrick County Agent, Cherokee County Alabama Cooperative Extension System Bobby Durbin Superintendent Field Crops Unit, E.V. Smith Research Center Shorter, Alabama Wilson H. Faircloth Graduate Research Assistant Agronomy and Soils, Auburn University Barry L. Freeman Extension Entomologist Entomology and Plant Pathology Auburn University William S. Gazaway Professor and Extension Specialist, Emeritus Entomology and Plant Pathology Auburn University Kathy Glass Agricultural Program Associate II Agronomy and Soils, Auburn University Curtis Grissom County Agent Coordinator, Limestone County Alabama Cooperative Extension System Bob Goodman Associate Professor Agricultural Economics and Rural Sociology Auburn University David H. Harkins Agricultural Program Assistant Tennessee Valley Research and Extension Center, Belle Mina, Alabama Kara Harris Department of Plant and Soil Science Alabama A&M University J. L. Hutchinson Graduate Research Assistant Entomology and Plant Pathology Auburn University J. Jenkins USDA/ARS/CSRL, Mississippi State, Mississippi 3. R. Jones Graduate Research Assistant Entomology and Plant Pathology Auburn University G. W. Lawrence Entomology and Plant Pathology Mississippi State University Kathy S. McLean Assistant Professor Entomology and Plant Pathology Auburn University B. A. Meyer District Technical Services Manager Delta and Pine Land Company Hartselle, Alabama Charles Mitchell Professor and Extension Agronomist Agronomy and Soils, Auburn University C. Dale Monks Professor and Extension Specialist Agronomy and Soils, Auburn University Don R Moore Superintendent Prattville Agricultural Research Unit E. Z. Nyakatawa Department of Plant and Soil Science Alabama A&M University Bobby E. Norris Superintendent Tennessee Valley Research and Extension Center, Belle Mina, Alabama Aaron J. Palmateer Graduate Research Assistant Entomology and Plant Pathology Auburn University Michael G. Patterson Professor, Agronomy and Soils Auburn University M. D. Pegues Associate Superintendent Gulf Coast Research and Extension Center Fairhope, Alabama K.C. Reddy Department of Plant and Soil Science Alabama A&M University D. W. Reeves USDA-ARS Research Leader Watkinsville, Georgia Maria Rivas Research Associate II, Plant Pathology Auburn University Govind Sharma Department of Plant and Soil Science Alabama A&M University J. N. Shaw Associate Professor, Agronomy and Soils Auburn University Edward Sikora Associate Professor Entomology and Plant Pathology Auburn University Ron H. Smith Professor and Extension Entomologist Entomology and Plant Pathology Auburn University Khairy Soliman Department of Plant and Soil Science Alabama A&M University Yonathan Tilahun Department of Plant and Soil Science Alabama A&M University Kevan Tucker Extension Agent, Marengo County Alabama Cooperative Extension System Ted Tyson Associate Professor and Extension Specialist Biosystems Engineering Auburn University S. R. Usery, Jr. Undergraduate Research Fellow Entomology and Plant Pathology Auburn University E. van Santen Professor, Agronomy and Soils Auburn University James R. Weeks Associate Professor and Extension Specialist Entomology and Plant Pathology Larry W. Wells Superintendent Wiregrass Research and Extension Center Headland, Alabama Anthony Wiggins Multicounty Extension Agent, Monroe County Alabama Cooperative Extension System Zhengdao Wu Department of Plant and Soil Science Alabama A&M University Rudy Yates Extension Agent, Dallas County Alabama Cooperative Extension System Allan Zipf Department of Plant and Soil Science Alabama A&M University VARIETY TRIALS CHEROKEE COUNTY COTTON VARIETY TRIAL Charles Burmester and David Derrick Each season a cotton variety trial is conducted in Chero- kee County to supplement yield results from the Alabama Cot- ton Variety Trials. This large cotton growing area has unique soil types and farmers often use results of this test to evaluate new cotton varieties for northeast Alabama. In 2002, the trial was conducted on the farm of Randall and Nick McMichen on a Holston fine sandy loam soil. Cotton was planted into a winter cover crop of wheat on April 26 and consisted of eight rows of each variety planted the length of the field. A total often cotton va- rieties were planted in 2002. All varieties were genetically modified and contained the Roundup Ready gene that al- lows weed control applica- tions with Roundup Ultra until the 4 th leaf stage. The cotton variety FiberMax 989 BR was used as a check variety be- tween each plot to detect soil variability. All varieties were spindle picked, and seed cot- ton weighed in a boll buggy. A seed cotton sample from each variety was ginned on a tabletop gin for lint percentage and quality. Dry growing conditions in 2002 limited yields; however, this test site still produced over two bale yields (see table). Insect pressure was low and only minimal control measures were required. Yields of Deltapine DP 555 BG/RR and Paymas- ter PM 1218 BG/RR lead this test in 2002. Cotton quality was excellent with all varieties with no discounts for staple, micronaire, or strength. Deltapine DP 555 BG/RR had the high- est lint percentage of all varieties tested. YIELD AND QUALITY OF COTTON VARIETIES IN THE CHEROKEE COUNTY TRIAL Variety' Seed cotton Lint yield Lint 2 yield Mic. Length Unif. 4 Strength Ibs/ac % lbs/ac units staple % g/tex Deltapine DP 555 BG/RR 3150 46.5 1460 4.6 34 81 28.6 Paymaster PM 1218 BG/RR 3390 42.8 1450 4.8 34 83 28.4 Deltapine DP 215 BG/RR 3190 41.3 1320 4.4 34 83 27.1 Deltapine DP 1199 BG/RR 2930 42.7 1250 4.6 35 83 30.1 Sure-Grow 521 R 2910 42.5 1240 4.6 34 83 27.9 FiberMax FM 989 BR 2890 41.8 1210 4.3 35 82 31.8 FiberMax FM 989 RR 2790 43.0 1200 3.9 34 83 30.9 Stoneville ST 4793 R 2760 42.8 1180 4.6 34 84 28.9 Deltapine DP 451 B/RR 2870 39.2 1130 4.7 35 83 27.3 1Stoneville 4892 BR yields are not reported due to a poor stand in part of the field. 2 Lint % determined on a small cotton gin without cleaners. This percentage is usually higher than normal turn-out at a cotton gin. Mic.=micronaire. 4 Unif.=uniformity. 2002 MONROE COUNTY ROUNDUP READY COTTON VARIETY TRIAL Dennis Delaney, C. Dale Monks, Anthony Wiggins, and Kathy Glass One of the most critical decisions a cotton producer makes each year is which variety to plant. Many factors, such as yield potential and lint quality, are heavily influenced by seed selec- tion. Area cotton producers often ask for more site-specific information on the unique soils and situations on their farms. On-farm field trials are important to verify university research and to show how different varieties perform under typical man- agement practices in producers' fields. A field was selected on the David Majors farm near Excel in Monroe County on a Malbis loam soil. Fertilization, weed, and insect control was maintained at optimum levels, per Ala- bama Cooperative Extension System recommendations. The same production practices were carried out across all varieties, regardless of technology or genetically engineered traits. Twelve cotton varieties, all containing the Roundup ReadyR gene were planted on April 23,2002, with three replica- tions of each variety in a randomized complete block design. Each plot was eight field-length rows of a single variety, with plot size ranging from 0.5 to 0.7 acre each. The plots were harvested on October 3 with a spindle picker. A weighing boll buggy was used to weigh each plot, and a grab sample taken. One-pound samples were ginned on a I :,c3 ALABAMA AGRICULTURAL EXPERIMENT STATION mini-gin, and analyzed with HVI equipment at the USDA-AMS Birmingham Classing Office. The cotton industry has renewed emphasis on lint quality in recent years, and producers have asked to see "value per acre" data in addition to lint yield per acre. Results are pre- sented in the following table, with varieties ranked by value in $/acre, with lint yield, turnout, and quality. Ratings for each variety also listed. Value per acre was determined from the USDA loan chart, assuming a base of $0.5275/1b of lint for SLM-41, leaf= 4, and adding or subtracting values taken from the chart for micronaire, length, and strength. No adjustments were made for seed costs or other cultural expenses. Producers can modify these numbers as needed for their particular situation. Results showed that there was a range in total value of over $110 per acre from the lowest to highest valued variety, or 215 pounds per acre of lint. There were also significant differ- ences in quality and other measurements. Area cotton producers can use these results to compare the performance of these varieties, with the potential for sig- nificantly higher returns from their crop. Producers should not rely on any single source, however, to guide their choices, but should also use other information such as the multi-year data from the Alabama Agricultural Experiments Station Official Va- riety Trials, and other public and private sources. MONROE COUNTY COTTON VARIETY TRIAL Lint Lint yield Turnout Mic. Length Strength Uniformity value Value' Name lb/ac % units in g/tex % cent//b $/ac Deltapine DP 555 BG/RR 792 45 42.0 1.06 26.9 82 52.90 418.97 Deltapine DP 5415 RR 747 42 48.7 1.07 27.4 83 53.00 395.91 Sure-Grow 215 BG/RR 763 42 47.3 1.02 25.0 . 82 49.40 376.92 Deltapine DP 655 B/RR 693 40 44.3 1.07 28.8 81 52.75 365.56 Sure-Grow 501 BR 731 42 48.7 1.04 27.8 82 50.00 365.50 FiberMax FM 991 RR 674 41 44.0 1.09 29.2 83 54.20 365.31 Stoneville ST 4892 BR 773 44 50.3 1.03 26.8 82 46.05 355.97 Deltapine DP 451 B/RR 662 39 46.0 1.06 26.6 81 52.75 349.21 Deltapine DP 436 RR 661 38 47.4 1.07 26.0 82 52.75 348.68 FiberMax FM 989 RR 629 42 42.4 1.08 29.5 83 54.70 344.06 Stoneville ST 4793 RR 661 44 48.3 1.04 27.1 82 50.00 330.50 FiberMax FM 989 BR 577 42 43.7 1.05 29.1 81 52.75 304.37 LSD (P=.10) 83 1.2 2.7 0.04 1.4 1 1 Value = $0.5275 per pound of lint for SLM41, if =4, plus or minus loan premiums and discounts. No TILL COTTON VARIETIES AT E.V SMITH Dennis Delaney, Kathy Glass, C. Dale Monks, and Bobby Durbin An i sieng acreage of cotton in Alabama is planted using conservation tillage of some kind; consequently, grow- ers have asked for information about performance of cotton varieties within the conservation tillage systems they use on their farms. The objective of this test was to compare the suit- ability of several commercially available cotton varieties in a strip till conservation tillage system. Twenty-five selected varieties were planted on a Cowarts loamy sand at the E.V. Smith Field Crops Unit on April 26 into a rye cover crop, which had been killed a month earlier. After in- row subsoiling, four replications of two 40-inch rows, 20 feet long of each variety were planted with a no-till planter equipped with row cleaners and spoked closing wheels. Fertility and pes- ticide applications were according to Alabama Cooperative Extension System recommendations. Insect pressure was rela- tively heavy, and nine foliar insecticide applications were made. Hail and wind damage in June and late summer dry weather affected yields. Plots were defoliated on September 9; the defoliant in- cluded a boll opener. Fifty-boll samples were taken from two replications, and then ginned on a mini-gin for lint quality and turnout. Plots were spindle-picked on September 19, and seed cotton weighed for yield. Yield and turnout results are presented in the table. Lint yields ranged from 915 to nearly 1300 pounds per acre. Lint turnout ranged from 35 to 41%. Producers can use these re- sults to compare the relative performance of these varieties in various management systems. 2 2002 COrrON RESEARCH REPORT 3 E.V. SMITH No TILL COTTON VARIETY TEST, 2002 Lint yield Turnout Lint yield Turnout Variety lb/ac % Variety lb/ac % PhytoGen PSC 355 1293 38 FiberMax FM 989 BR 1042 37 Sure-Grow 747 1288 40 FiberMax FM 958 1041 39 Stoneville ST 4892 BR 1252 39 Deltapine NuCotn 33B 1023 35 Deltapine DP 436 RR 1219 34 Sure-Grow 501 BR 988 37 FiberMax FM 966 1190 39 Deltapine DP 565 969 36 Deltapine DP 555 BG/RR 1181 40 Deltapine DP 655 B/RR 969 35 Sure-Grow 521 R 1150 37 PhytoGen PSC HS-12 946 36 Stoneville ST 4793 R 1132 39 DP Delta Pearl 934 38 Deltapine DP 5415 RR 1119 38 FiberMax FM 991 R 919 35 Stoneville ST 580 1092 36 Paymaster PM 1218 BG/RR 915 39 Deltapine DP 458 B/R 1083 37 FiberMax FM 989 R 895 38 PhytoGen PSC GA 161 1074 35 Stoneville ST 5599 BR 866 41 Sure-Grow 215 BG/RR 1061 38 LSD (P=.10) 131 1 VARIETY EVALUATION IN ULTRA NARROW Row COTTON AT De laney, Kathy Glass, C. Dale Monks, and Bobby Durbin The objective of this test was to compare the suitability of several picker type cotton varieties for use in an Ultra Nar- row Row system. Variety selection is one of the most important decisions a cotton producer must make, and little information is available about how different cultivars perform in this pro- duction system. Twenty selected varieties were planted at the E.V. Smith Field Crops Unit on April 6, 2002 using a small plot drill. Ap- E.V. SMITH proximately 180,000 seed per acre were planted in 7-inch rows in plots 10.5 feet wide by 25 feet long. Conventional soil-ap- plied herbicides were used to control weeds, and insects were controlled by foliar materials. A total of 100 pounds per acre of N was applied at planting, with other fertilizers according to soil test. A total of 8 ounces per acre Pix Plus? was applied in two applications. The test was defoliated on August 27, and desic- YIELD AND QUALITY OF COTTON VARIETIES IN ULTRA NARROW Row TRIAL AT E.V. SMITH Variety' Lint yield Turnout Mic. Length Strength lbs/ac % units in g/tex FiberMax FM 966 1284 37 37.0 1.11 32.9 Phytogen PSC 355 1185 35 39.0 1.10 29.5 Stoneville ST 5599 BR 1082 37 34.0 1.06 28.1 FiberMax FM 958 1056 36 32.0 1.09 31.3 Stoneville ST 580 1046 32 38.0 1.05 29.3 Paymaster PM 1218 BG/RR 1044 36 43.0 1.01 26.2 Deltapine DP 5415 RR 1039 32 34.0 1.06 28.5 Stoneville ST 4892 BR 1028 34 39.5 1.06 29.4 Deltapine NuCotn 33B 1016 32 37.0 1.14 28.5 Deltapine 458 B/R 1008 33 36.0 1.08 29.3 FiberMax FM 991 R 1004 32 34.0 1.08 32.3 Stoneville ST 4793 R 993 35 39.0 1.08 29.0 Sure-Grow 501 BR 992 31 41.0 1.01 28.7 Deltapine DP 555 BG/RR 988 37 37.5 1.09 27.6 Deltapine DP 436 RR 948 32 37.0 1.07 27.1 Deltapine DP 655 B/RR 875 32 32.5 1.02 29.3 FiberMax FM 989 BR 875 33 34.5 1.04 29.1 LSD (P=.10) 111.1 1.8 4.5 0.03 1.4 cated on September 3. The cen- ter 7 feet by 25 feet of each plot was harvested on September 6 with a stripper equipped with a broadcast header. Grab samples from the center two replications were cleaned, ginned on a mini-gin, and lint was analyzed by HVI. Results are presented in the table. Approximately one- third of the test was affected by a poor stand, and these plots were not harvested or included in the results. Lint yields ranged from 875 to 1284 pounds per acre, while lint turn- out from grab samples ranged from 31 to 37%. There were also several statistical differences in lint quality. ALABAMA AGRICULTURAL EXPERIMENT STATION 2002 FUSARIUM WILT/COMMERCIAL Kathy Glass and William Gazaway Fifteen commercial cotton varieties commonly grown in Alabama were evaluated for Fusarium wilt resistance at the E.V. Smith Research Center, Plant Breeding Unit, Tallassee, Alabama. Varieties were planted on a Wickham fine sandy loam in single 20-foot rows on 40-inch centers, separated by 5-foot alleys. Four replications of the test entries and the susceptible check variety Rowden were evaluated in a randomized complete block design. Plots were planted on May 22, 2002, with Ridomil at 8 pounds per acre applied in the seed furrow at planting. Initial plant counts were made on June 20. Wilted plants were counted and removed on July 10, July 31, August 20, and September 3. The remaining live plants were counted and recorded on Sep- tember 3. Total percent wilted plants were determined by the ratio of removed to wilted plants and mean wilting for a given variety was calculated. COTTON VARIETY TEST AVERAGE PERCENT OF WILTED PLANTS Average wilt Variety % Rowden 1 76 FiberMax FM 958 32 Stoneville ST 4793 R 20 Stoneville ST 4892 BR 20 Stoneville ST 580 18 Paymaster PM 1218 BG/RR 17 Deltapine DP 555 BG/RR 15 Deltapine DP 491 12 Sure-Grow SG 215 BG/RR 12 PhytoGen PSC 355 11 FiberMax FM 991 RR 10 FiberMax FM 989 BR 10 Deltapine DP 458 B/R 8 Deltapine DP 5690 RR 7 PhytoGen PSC GA 161 7 Sure-Grow SG 501 BG/RR 7 'Rowden is extremely susceptible to Fusarium wilt. EVALUATION OF EARLY SEASON COTTON VARIETIES FOR RESPONSE TO BOLL ROT DISEASE IN ALABAMA A. J. Palmateer, K. S. McLean, G. W. Lawrence, J. L. Hutchinson, J. R. Jones, K. Glass, and M. D. Pegues A cotton variety trial was planted on May 9 at the Auburn University, Gulf Coast Research and Extension Center, Fairhope, Alabama. Plots consisted of two rows, 25 feet long, with a between-row spacing of 40 inches. Plots were arranged in a randomized complete-block design with four replications. A 20- foot alley separated blocks. Cotton boll rot was evaluated by recording the number of healthy bolls and diseased bolls from a one thousandth of an acre section within each plot. Percent diseased bolls ([number of diseased bolls divided by total num- ber counted] x 100) were calculated for each variety. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production prac- tices as recommended by the Alabama Cooperative Extension System. Plots were harvested on November 25. Data were sta- tistically analyzed using PROC GLM and means compared with Fisher's protected least significant difference test (P<0.05). Cotton boll rot disease incidence was high in 2002 due to tropical storms and hurricane conditions late in the season. The disease index for boll rot ranged from 30.4% for Texas 295 to a low rating of 7% for Deltapine DP 555BG/RR. Lint cotton yields varied by 784 pounds per acre between the Sure-Grow 105 and Deltapine NuCotton 33B varieties. 4 VISLIIL L;UUIIL~ Wt;lE; IIISLUt; V11J UIIC; LV. VV IILt;U VlilllLY WE;lt; C;VUIILt;U 2002 Co-rroN RESEARCH REPORT 5 EVALUATION OF EARLY SEASON COTTON VARIETIES FOR RESPONSE To BOLL ROT DISEASE IN ALABAMA, 2002 Variety Healthy bolls' Diseased bolls' Disease index 2 Seed cotton yield no. no. lb/ac Deltapine NuCotton 33B 73.8 ab 3 11.5 abc 17.0 abc 898.5 e Deltapine DP 451B/RR 53.3 bcd 11.8a bc 30.0 a 1357.0 a-d Sure-Grow 747 67.8 bc 9.3 abc 14.6 abc 1471.8 a-d Sure-Grow 105 55.8 bcd 11.5a bc 28.8 ab 1682.0 a Deltapine DP 436RR 45.0 d 10.5 abc 24.3 abc 1333.3 a-d PhytoGen PSC 355 64.3 bcd 16.3 ab 30.2 a 1089.8 de Stoneville ST 4892BR 69.5 bc 8.5 bc 12.9 abc 1333.5 a-d Sure-Grow 501BR 63.3 bcd 12.3 abc 18.4 abc 1228.5 b-e Paymaster PM 1218BG/RR 67.0 bc 7.3 c 10.7 abc 1295.0 a-d FiberMax FM 966 64.0 bcd 9.0 abc 14.2 abc 1586.3 ab Sure-Grow 521R 61.8 bcd 8.8 bc 14.1 abc 1127.8 cde Sure-Grow 215BR 73.0 ab 8.0 bc 11.5 abc 1123.3 cde Paymaster PM 1199 RR 63.5 bcd 6.0 c 9.2 bc 1237.5 b-e Stoneville ST 4793R 55.0 bcd 9.5 abc 19.4 abc 1491.3 abc Deltapine DP 555BG/RR 92.8 a 6.5 c 7.0 c 1500.5 abc Deltapine DP 99X35 58.8 bcd 13.5 abc 24.9 abc 1414.3 a-d PhytoGen PH98M-2983 50.0 cd 13.3 abc 27.7 ab 1376.3 a-d FiberMax 958 51.0 cd 8.8 bc 17.2 abc 1151.8 cde Stoneville ST 457 57.5 bcd 10.0 abc 17.8 abc 1438.5 a-d Texas 28R 57.3 bcd 13.8 abc 23.8 abc 1428.8 a-d Texas 30R 70.5 bc 17.3 a 24.6 abc 1457.5 a-d Texas 295 52.0 bcd 16.0 ab 30.4 a 1132.5 cde LSD (P<0.05) 21.8 8.4 20.2 393.5 SNumber of bolls per 50 ft of row. 2 Disease index = (number of diseased bolls / number of total boils) x 100. 3 Means within columns followed by the same letter are not significantly different according to Fisher's protected least significant difference test (P = 0.05). EVALUATION OF FULL SEASON COTTON VARIETIES FOR RESPONSE TO BOLL ROT DISEASE IN ALABAMA A. J. Palmateer, K. S. McLean, G. W. Lawrence, 3. L. Hutchinson, 3. R. Jones, K. Glass, and M. D. Pegues A cotton variety trial was planted on May 9 at the Gulf Coast Research and Extension Center, Fairhope, Alabama. The soil type was a Malbis fine sandy loam. Plots consisted of two rows, 25 feet long, with a between-row spacing of 40 inches. Plots were arranged in a randomized complete block design with four replications. A 20-foot alley separated blocks. Cot- ton boll rot was evaluated by recording the number of healthy bolls and diseased bolls from a thousandth acre section within each plot. Disease index ([number of diseased bolls divided by the total number counted] x 100) was calculated for each vari- ety. Plots were maintained throughout the season with stan- dard herbicide, insecticide, and fertility production practices as recommended by the Alabama Cooperative Extension Sys- tem. Plots were harvested on November 25. Data were statis- tically analyzed using PROC GLM, and means were compared with Fisher's protected least significant difference test (P < 0.05). Cotton boll rot disease incidence was high for early- planted cotton in 2002 due to tropical storms and hurricane conditions. Disease index for boll rot ranged from 69% for PhytoGen Phy 78 Acala to a low rating of 5% for Stoneville ST 4892BR. Lint cotton yields between GC-271 and DP Delta Pearl varied by 755 pounds per acre. - 6 ALABAMA AGRICULTURAL EXPERIMENT STATION EVALUATION OF FULL SEASON COTTON VARIETIES FOR RESPONSE To BOLL ROT DISEASE IN ALABAMA, 2002 Variety Healthy bolls' Diseased bolls' Disease index 2 Seed cotton yield no. no. Ib/ac Deltapine DP 5415 67.8 a-d 3 13.8 bcd 15.8 bcd 1424.3 a-d Deltapine DP 35B 68.0 abc 16.0 bc 18.9 bcd 1343 a-d Deltapine DP 5415 RR 56.0 a-d 17.8 b 23.4 bc 1314.3 a-d Deltapine DP 5690 RR 77.5 a 10.5 b-e 12.5 cd 1515.0 a-d Deltapine DP 448B 52.3 bcd 16.5 bc 23.8 bc 1118.5 bcd PytoGen PSC 161 45.8 d 13.0 bcd 22.6 bc 1343.0 a-d FiberMax FM 989 46.8 cd 14.8 bc 23.3 bc 1596.0 ab AP 7126 62.5 a-d 10.5 b-e 14.7 bcd 1280.5 a-d Deltapine DP 458B RR 60.3 a-d 12.0 b-e 17.2 bcd 1065.8 cd Deltapine DP655 BRR 61.5 a-d 7.0 cde 10.0 cd 1581.5 abc PytoGen PSC 12 51.5 bcd 12.3 c-e 19.9 bcd 1366.5 a-d DP Delta Pearl 59.8 a-d 12.5 c-e 17.1 bcd 1027.5 d Deltapine DP 565 51.5 bcd 14.8 bc 22.5 bc 1400.3 a-d Deltapine DP 491 49.5 bcd 13.3 bcd 24.7 bc 1558.0 abc GC-271 56.5 a-d 9.3 c-e 14.1 cd 1782.5 a Stoneville ST 580 58.5 a-d 13.3 bcd 18.6 bcd 1443.5 a-d Stoneville ST 5599 BR 61.0 a-d 13.5 bcd 18.4 bcd 1232.8 bcd FiberMax FM 989 BR 64.8 a-d 12.5 c-e 16.2 bcd 1295.0 a-d FiberMax FM 989 RR 56.3 a-d 10.5 c-e 18.1 bcd 1538.8 a-d FiberMax FM 99 1R 49.8 bcd 9.3 c-e 18.4 bcd 1290.3 a-d Stoneville ST 0003 63.5 a-d 4.3 de 6.1 d 1438.5 a-d Texas 24R 67.8 a-d 13.5 bcd 17.8 bcd 1319.0 a-d Texas 245 47.3 bcd 17.5 b 29.7 b 1319.0 a-d PhytoGen Phy 78 Acala 20.0 e 45.8 a 69.9 a 1257.0 bcd Deltapine NuCotton 33B 64.8 a-d 14.0 bc 17.8 bcd 1180.5 bcd Deltapine 555 BGBR 57.0 a-d 11.0 b-e 16.8 bcd 1491.0 a-d Sure-Grow 747 62.0 a-d 7.8 cde 11.1 cd 1510.0 a-d Stoneville ST 4892 BR 69.0 ab 3.3 e 5.1 d 1323.8 a-d LSD (P< 0.05) 22.1 9.5 15.2 523.2 1 Number of bolls per 6 ft of row. 2 Disease index = (number of diseased bolls / number of total bolls) x 100. 3 Means within columns followed by the same letter are not significantly different according to Fisher's protected least significant difference test (P = 0.05). TRANSGENIC COTTON VARIETY RESPONSE TO ROTYLENCHULUS RENIFORMIS ON COTTON FOLLOWING CORN IN NORTH ALABAMA S. R. Usery Jr., K. S. McLean, C. H. Burmester, B. A. Meyer, and E. van Santen Cruiser-treated transgenic cotton varieties were examined with and without Temik 15G for their response to the reniform nematode (Rotylenchulus reniformis) following corn in north Alabama. The test was planted on April 22 in a producer's field naturally infested with the reniform nematode after a year of corn production. The soil was a Decatur silt loam. Temik 15G at 3.5 pounds per acre was applied at planting in the seed furrow with chemical granular applicators attached to the planter. Plots consisted of one row, 200 feet long with 36-inch row spacing. All plots were maintained with standard production prac- tices recommended by the Alabama Cooperative Extension Sys- tem commonly used in the area. Plots were not irrigated. Popu- lation densities of reniform nematode were determined at plant- ing, peak bloom, and harvest. Each row was sampled individu- ally in a systematic sampling pattern. Nematodes were extracted using gravity sieving and sucrose centrifugation technique. Plots were harvested on November 11. Mixed models analysis of variance with nearest neighbor adjustment (NNA) was con- __ _____ -_ __ _ . _ 1 2002 CorroN RESEARCH REPORT 7 ducted using the average residual of adjacent plots as a plus Temik and Sure-Grow 521 R with no Temik, respectively. covariate. Least squares means are reported with standard er- Temik 15 G application had no effect on seed cotton yield, rors. except for Deltapine DP 436 RR, Sure-Grow 521R, and Sure- Reniform nematode numbers increased in all of the plots. Grow 501 BR, where Temik-treated plots yielded significantly Reproductive factors (rf) varied from lowest in DP 5415 no Temik less (average of 192 pounds per acre). The phenotypic correla- treatment to highest in the ST 4892 BR no Temik treatment. All tion between rf and cotton seed yield was non-significant. The varieties and treatments produced an rf value of greater than 1, absence of a treatment effect is likely the result of the extremely which indicated reniform nematodes were increasing. Cotton low reniform populations in this field at planting following the seed yield varied 629 pounds per acre for Stoneville ST 4793 R previous year in corn production. TRANSGENIC COTTON VARIETY RESPONSE TO ROTYLENCHULUS RENIFORMIS ON CorroN FOLLOWING CORN IN NORTH ALABAMA, 2002 Treatment Reniform Reniform Reniform reproduction Yield seed cotton 2 at planting -at harvest'- - factor' b/ac Temik no Temik Temik no Temik Temik no Temik Deltapine DP 5415 RR 33.4 924 747 27.7 22.4 2241 2369 Stoneville ST 4793 R 33.4 1008 2285 30.2 68.4 2097 2107 Deltapine DP 436 RR 33.4 1226 916 36.7 27.4 2215 2474 Sure-Grow 521 R 33.4 1100 1021 32.9 30.6 2572 2726 Paymaster PM 1199 R 33.4 1091 1959 32.7 58.6 2433 2561 Stoneville ST 4892 BR 33.4 1766 2210 52.9 66.2 2494 2465 Sure-Grow 501 BR 33.4 1940 1650 58.1 49.4 2555 2717 Sure-Grow 215 BR 33.4 782 1650 23.4 49.4 2415 2482 Paymaster PM 1218 BG/RR 33.4 1206 2036 36.1 61.0 2206 2326 Deltapine DP 451 B/RR 33.4 1110 1804 33.2 54.0 2136 2247 Standard Error - 278- - 9.4--- 55.4-- ' Variety x treatment interaction was significant with a calculated P < 0.01. 2 Variety x treatment interaction was non-significant (P = 0.18). The variety effect was significant with P = 0.001. TRANSGENIC COTTON VARIETY RESPONSE TO ROTYLENCHULUS RENIFORMIS ON MONOCULTURED COTTON IN NORTH ALABAMA S. R. Usery Jr., K. S. McLean C. H. Burmester, B. A. Meyer, and E. van Santen Transgenic cotton varieties were examined with and with- out Temik 15G for their response to the reniform nematode (Rotylenchulus reniformis) in north Alabama. The test was planted on April 18 in a producer's field naturally infested with the reniform nematode and monocultured in cotton. The soil was a Decatur silt loam. Temik 15G at 5.0 pounds per acre or Di- Syston 15 G at 6.0 pounds per acre were applied at planting in the seed furrow with chemical granular applicators attached to the planter. Plots consisted of two rows, 25feet long with a 40- inch row spacing. All plots were maintained with standard production prac- tices recommended by the Alabama Cooperative Extension Sys- tem and commonly used in the area. The plots were irrigated. Population densities of the reniform nematode were determined at planting, peak bloom, and harvest. Soil cores, 1-inch diam- eter and 8-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 centrifuga- tion technique. Plots were harvested on September 30. Mixed models analysis of variance with nearest neighbor adjustment (NNA) was conducted using the average residual of adjacent plots as a covariate. Least squares means are reported with standard errors. Reniform nematode numbers increased from planting to harvest in 83% of the plots as indicated by reproductive fac- tors (rf) exceeding 1. Rfs varied from 0.83 for Paymaster PM 1218 BG/RR with Temik to 3.17 for FiberMax FM989 RR also with Temik. No variety exhibited an rf below 1 with Temik and ALABAMA AGRICULTURAL EXPERIMENT STATION Di-Syston. Cotton seed yield varied 829 pounds per acre for two varieties PM 1218 BG/RR and SG 215 BG/RR for which the Deltapine DPL 458 B/RR and Sure-Grow 215 BG/RR, both with Di-Syston treatment significantly (P = 0.10) out yielded the Temik. There was no correlation between yield and rf for either Temik treatment. These two varieties may have some tolerance Temik or Di-Syston treated plots. Of particular interest are the to R. reniformis. TRANSGENIC COTTON VARIETY RESPONSE TO ROTYLENCHULUS RENIFORMIS ON MONOCULTURED COTTON IN NORTH ALABAMA, 2002 Treatment Reniform Reniform Reniform reproduction Yield seed cotton 2 at planting -- at harvest'- - factor'- b/ac Temik Di-Syston Temik Di-Syston Temik Di-Syston Deltapine DP 5415 RR 5112 5613 4241 1.10 0.85 2830 2833 Stoneville ST 4892 BR 4414 6481 4741 1.47 1.07 2894 2678 Deltapine DP 451 B/RR 3960 6151 5005 1.55 1.26 2976 3071 Deltapine DP 436 RR 5064 4460 6143 0.88 1.21 2974 3060 Deltapine DPL 458 B/RR 3580 8586 8014 2.40 2.24 2725 2532 FiberMax FM 989 RR 2441 7744 5375 3.17 2.20 3022 3011 Paymaster PM 1218 BG/RR 3675 3116 3917 0.83 1.07 3169 3308 Sure-Grow 215 BG/RR 4667 5884 4412 1.26 0.95 3129 3361 Paymaster PM 1199 RR 3675 6205 6546 1.69 1.78 3010 2838 Stoneville ST 4793 R 4010 4906 5411 1.22 1.35 2874 2832 Deltapine DP 555 BG/RR 4301 4378 5785 1.02 1.35 2619 2644 FiberMax FM 989 BR 3462 6294 6412 1.82 1.85 3030 2771 Standard Error 465 - 790- 55- 'Variety x treatment interaction was non-significant (P = 0.24). The variety effect was significant with P =0.001. 2Variety x treatment interaction was significant with a calculated P = 0.0002. 8 2002 COTTON RESEARCH REPORT CROP PRODUCTION WEED POPULATION DYNAMICS UNDER GLYPHOSATE-RESISTANT COTTON CROPPING SYSTEMS Wilson H. Faircloth and Michael G. Patterson Concerns about the effect of intense glyphosate applica- tions on continuous cotton cropping systems have increased as glyphosate-resistant cotton varieties have exceeded 90% of the cotton acreage planted in Alabama. Consequently, there is the potential for this intense usage to shift weed populations toward more tolerant species and, ultimately, resistance. Field studies were implemented in 2000 at the Tennessee Valley Research and Extension Center, Belle Mina, and at the SICKLEPOD AND PITTED MORNINGGLORY RESPONSE TO INTE Sicklepod Herbicide Rate Application timing p lb ailac 1 glyphosate 3 0.5 POT-1 4 7 glyphosate 0.5 POT-4 glyphosate 0.5 PDS-12 2 glyphosate 0.5 POT-4 8 glyphosate 0.5 PDS-8 glyphosate 0.5 PDS-12 3 glyphosate 1.0 POT-1 3 glyphosate 1.0 POT-4 glyphosate 1.0 PDS-12 4 glyphosate 0.5 POT-1 3 +pyrithiobac +0.04 glyphosate 0.75 PDS-8 glyphosate 0.5 PDS-12 5 glyphosate 0.5 POT-4 5 +pyrithiobac +0.04 glyphosate 0.75 PDS-8 prometryn 0.75 PDS-12 +MSMA +1.5 6 fluometuron 1.5 PRE 4 glyphosate 0.5 POT-4 glyphosate 0.5 PDS-12 7 fluometuron 1.5 PRE 4 glyphosate 0.5 POT-4 +pyrithiobac +0.04 glyphosate 0.5 PDS-12 8 weed-free - - 5 LSD (P < 0.05) NS 1 Plant density (August 2001) at the conclusion of a 2-year study. 2 Sicklepod data pooled over pendimethalin usage. SGlyphosate product used: Roundup, 4 Ib ai/gal (3 Ib ae/gal). 4 Abbreviations: POT-1, postemergence over-the-top 1 leaf; POT top 4 leaf; PDS-8, postemergence directed spray 8 leaf; PDS-12, p 12 leaf; PRE, preemergence; NS, not statistically significant. E.V. Smith Research Center, Field Crops Unit, Shorter, to study the effect of intense glyphosate usage on sicklepod (Senna obtusifolia) and pitted morningglory (Ipomoea lacunosa) popu- lations. Experimental units consisted of glyphosate-resistant cotton varieties (Sure-Grow 125 BR, Belle Mina; Sure-Grow 501 BR, Shorter) planted in four 40 inch rows, 25 feet long at each location. Cotton was planted and maintained with conventional tillage practices and the Alabama Cooperative Extension System's recommendations for fertility and non-weed pests. SNSE GLYPHOSATE USAGE 1 ' 2 Treatments consisted of Plant density three applications of -Pitted morningglory- glyphosate at either one-half With Without time or one time (one time )endimethalin pendimethalin equals one pound active ingre- -no. plants/plot dient per acre) rates applied at 20 66 various times including postemergence over-the-top one leaf (POT-1), POT-4, 19 58 postemergence directed spray eight leaf(PDS-8), and PDS-12. 13 50 Variations on this basic pattern 13 50 included pyrithiobac (0.04 pound active ingredient per 18 40 acre) added to the POT-1 or POT-4 applications, prometryn (0.75 pound active ingredient per acre) plus MSMA (1.5 18 57 pounds active ingredient per acre) substituted for the PDS- 12 application, and fluometuron applied as a preemergence 5 22 (PRE) treatment (see table). A hand-weeded check plot was also maintained. These treat- 6 8 ments were applied with and without pendimethalin (0.8 pound active ingredient per 25 75 acre) preplant incorporated 25 (PPI), yielding a total of 16 treat- ments per site. Experimental design was a randomized complete block -4, postemergence over-the- with four replications. Plot in- )ostemergence directed spray tegrity was maintained over years at each location. The 9 ALABAMA AGRICULTURAL EXPERIMENT STATION glyphosate product used was Roundup Ultra, 4 pounds active ingredient per gallon (3 pounds acid equivalent [ae] per gallon). Response variables measured included the following: weed den- sity early (June), mid (July), and late season (August); visual con- trol and crop injury ratings (not presented); and crop yield. Baseline weed densities in a measurement plot (250 square feet) were re- corded at the onset of the studies: Belle Mina, pitted momingglory, 97 plants per plot; Shorter, sicklepod, 138 plants per plot. Pendimethalin showed no interaction for the plant density counts in the sicklepod study at Shorter (see table); therefore, treatments were combined in analysis. Treatments utilizing glyphosate alone at both the one-half time and one time rates had more sicklepod plants per plot than those where other herbicides were used in combination with glyphosate at the end of the 2000 growing season. The treatment that exhibited the fewest number of plants at the end of year one (five plants per plot) included both pyrithiobac and fluometuron. At the beginning of year two, all plots showed a greater number of emerged sicklepod seedlings (76 to 267 plants per plot), with no significant differences between treatments. This increase in density is likely due to a relatively wet spring as compared to 2000, which stimulated the large seedbank. At the conclusion of the 2001 growing season, sicklepod densities ranged from three to eight plants per plot with no significant differences between treat- ments. Seed cotton yield data exhibited a pendimethalin by year interaction; therefore, data were pooled accordingly due to ab- sence of treatment effects. Pendimethalin resulted in higher yields in both 2000 and 2001, likely due to early-season annual grass suppression. Seed cotton yields ranged from 1423 to 3274 pounds per acre. The effect of pendimethalin was significant in the pitted momrninglory study at Belle Mina (see table). Early season plant counts in 2000 revealed an increase in density when no pendimethalin was applied, being significantly higher for the glyphosate one-half time rate treatments and one treatment that included pyrithiobac in the POT (four leaf) application. When pendimethalin was not applied, those treatments utilizing the one time rate of glyphosate and/or the one-half time rate plus pyrithiobac and/or fluometuron PRE showed a decrease in plant densities. Mid-season evaluations for 2000 continued to exhibit the trend of glyphosate alone at the one-half time rate without pendimethalin treatments having significantly higher numbers of plants per plot. At the end of 2000, pitted momingglory counts ranged from zero to six plants per plot, with pendimethalin plots having significantly fewer plants per plot; however, these low numbers may be of no practical significance. No differences were detected between plots at the begin- ning of 2001. However, early evaluations again showed an in- crease in plant populations where pendimethalin was not applied, except for the fluometuron treatments, which showed no differ- ence. When pendimethalin was not applied, the addition of fluometuron to the treatment reduced the number of plants/plot significantly compared to other treatments. At the conclusion of the 2001 growing season, those treatments with glyphosate alone at the one-half time rate without pendimenthalin showed the high- est numbers of plants per plot, with all other plots being equal. Seed cotton yields at Belle Mina showed only a year main effect with 2001 yielding 61% higher than 2000, due to the much more favorable moisture conditions. In summary, at the conclusion of two years of repeated glyphosate and glyphosate-mixed treatments, no differences in sicklepod plant numbers were detected. Pitted morningglory oc- currence in glyphosate-only systems was higher, especially if the one-half time rate was utilized. Long-term management strategies for pitted momrningglory in glyphosate-resistant cotton might in- clude the use of pendimethalin. Further studies into the effective- ness of pendimethalin applied PRE for pitted morningglory man- agement would be critical for conservation tillage systems. EVALUATION OF SUBSURFACE IRRIGATION IN THE WIREGRASS Larry M. Curtis, William C. Birdsong, and Ted W. Tyson This project evaluating subsurface drip irrigation was initi- ated at the Wiregrass Research and Extension Center in the spring of 1999. Start up problems delayed planting the first year resulting in relatively poor yields relative to 2000, 2001 and 2002. The objectives of this project were (1) to evaluate subsur- face drip irrigation for cotton production in an application similar to typical field conditions in the Wiregrass; (2) to compare fertigation through drip irrigation versus conventional applica- tion of fertilizer; (3) to evaluate the effectiveness of subsurface drip irrigation using conventional tillage vs strip till; (4) to evalu- ate subsurface drip irrigation placed at 15 inches deep and at two flow rates (flow rates = 0.4 gallon per hour per emitter and 0.23 gallon per hour per emitter at 24-inch spacing); (5) to evaluate the reliability of subsurface drip irrigation in terms of longevity and plugging using traditional filtration and maintenance procedures; and (6) to compare yields for the fertigated and non-fertigated treatments, tillage treatments, flow rate treatments, and dry plot treatments in each of the above tests. Subsurface drip irrigation was plowed in between rows at a depth of approximately 14 to 16 inches. This product is being utilized to evaluate injection of liquid fertilizer through the system versus application in the traditional manner. Conventional tillage and strip-till practices are being compared. Two tape flow rates were evaluated with the quantity of water flowing through the system being monitored since installation. The system is main- tained with filtration, chlorine injection, and other maintenance procedures to keep the system open and flowing at the design flow rate. The tape is evaluated periodically through the season 10 liVVV~ **II1V11 r3CIIIIUILCL VU L IIV ILU6V OVVUVLU~ 1~C UIV VVIIVIUUIVII V1 VUC rlu lrvvrv vr YI 2002 CO-rTON RESEARCH REPORT and at the end of each season to determine if deterioration of flow is occurring. To date initial flows through the tape have been maintained. Yield determinations have been taken for each treat- Figure 1. Subsurface drip irrigation conventional till treatments, Headland. 4000 3500 LU .) 30001 Ui w 2500 ... o 2000 Co1500 100 500 .... 019.99: 0C32000 0.120.01 020 NOT IRRIGATED 1145 786 2822 2266 LOW FLOW~ FERTIGATE 1861 3250 3580 2871 11 ment and for non irrigated plots for the 4 years ofthe project. Yield results for 1999-2002 are illustrated in figures 1 and 2. Average yields for the 4 years are combined in figure 3. LOW FLOW-NOT F D FERTIGATED F 2291 2703 3445 3798 TREATMENT AND YIELD EACH YEAR uIGH FLOW- ERTIGATED 1511 2770 3217 3025 HIGH FLOW-NOT FERTIGATED 2222 2667 3553 3687 Figure 2. Subsurface drip irrigation no till treatments, Headland. K NOT IR RIGATED LOW FLOW- LOW FLOW-NOT HIGH FLOW- HIGH FLOW-NOT FERTIGATED FERTIGATED FERTIGATED FERTIGATED 2406 2120 3148 3857 TREATMENT AND YIELD EACH YEAR 4000 3500 3000 2500 w CL) z 0 0 w w z 0 CL 2 000 1500 1000 500 01999 032000 012001 0120.02 1385 926 3214 2457 1906 2198 2820 2891 2155 2508 3077 2809 2475 1967 3081 3282 I 12 Figure 3. Subsurface drip irrigation 4-year average, Headland. 3500 3000 2500 2000 1500 1000 uJ i! 0 0 z L- 0 0 w w 0 UL ?0 0 z 0 n~ 500 0 ALABAMA AGRICULTURAL EXPERIMENT STATION NOT IRRIGATED 1995 1755 LOW FLOW- FERTIGATED LOW FLOW-NOT FERTIGATED HIGH FLOW- FERTIGATED 2454 2883 2637 2890 3059 2631 POUNDS SEED COTTON PER TREATMENT HIGH FLOW-NOT FERTIGATED 2701 3032 SPRINKLER AND SUBSURFACE DRIP I GATION AT THE TENNESSEE VALLEY RESEARCH AND EXTENSION CENTER Larry M. Curtis, Charles H. Burmester, David H. Harkins, B. E. Norris, and James W. Baier Three experiments involving application and use of sprin- kler and subsurface drip irrigation continued in 2002 at the Tennessee Valley Research and Extension Center, Belle Mina, Alabama. The variety selections for each experiment are indi- cated in Table 1. The experiments were as follows. Sprinkler irrigation water requirements and irrigation scheduling. This experiment was established in 1999 to evalu- ate a range of irrigation application capabilities to identify the minimum design flow rate that will produce optimum yields. Treatments included four sprin- kler irrigation capabilities and a non-irrigated treatment. Irri- gation was managed using soil moisture sensors and Moiscot Sprinkler study (a spreadsheet-based schedul- ing method). The irrigation ca- 1998 pabilities were (1) 1 inch every 1999 Deltapine NuC 12.5 days, (2) 1 inch every 6.3 2000 Deltapine DP 4 days, (3) 1 inch every 4.2 days, 2001 Deltapine DP 4 and (4) 1 inch every 3.1 d 2002 Deltapine DP and (4) 1 inch days. This 1 inch represents the maximum amount of irrigation that could be applied in the time indicated. The results for 1999, 2000, 2001, and 2002 are presented in Figure 1. Irrigated yields in 2002 were significantly higher than non-irrigated yields but the highest yields were less than in previous years for most treatments. The reason for this is un- clear but may be related to shutdown of irrigation prior to suf- ficient boll maturity. Only very small yield differences were noted in 2001 while significant differences were measured in 1999 and TABLE 1. VARIETY SELECTION SDI Placement and SDI water management tape-fertigation study Deltapine NuCotn 33B Deltapine NuCotn 33B otn 33B Deltapine NuCotn 33B Deltapine NuCotn 33B 28 B Deltapine NuCotn 33B Deltapine DP 428 B 28 B Deltapine NuCotn 33B Deltapine DP 428 B 51B/RR Deltapine DP 451B/RR Deltapine DP 451B/RR O NO TILL 0 CONV. TILL ---- ------- ---- ------------ ----- ---- - ------- 2002 CoTroN RESEARCH REPORT Figure 1. Sprinkler irrigation cotton yield results. 4500 4000 3500 3000 2500 2000 1500 1000 500- 0 01999 Ei M2000 02001 2002 -- 1 NOT IRRIGATED 1"-12.5 DAYS 1"-6.3 DAYS 1"-4.2 DAYS 1"-3.1 DAYS 01999 1700 2637 2984 3708 3920 o2000 1236 2444 3688 3603 3627 S2001 3061 3387 3466 3595 3371 20021759 2530 2871 2853 2925 IDDIfATIfM VQTEIRA iADArITV 2000. Rainfall variability and treatment effects accounted for the wide range of yield responses for each of these years. Subsurface drip irrigation (SDI) placement and irriga- tion water requirements. This experiment was initiated in 1998 to evaluate placement of SDI relative to crop row direction and to evaluate water requirements for cotton production using SDI. Drip tubing was buried 15 inches deep with emitters at 2- 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 be- tween drip lines. Irrigation treatments were based on daily applications equal to 30%, 60%, and 90% of pan evaporation after full crop canopy with adjustments based on percent canopy prior to full canopy cover. Yield results for 5 years (1998 through 2002) are presented in Figure 2. TABLE 2. AVERAGE YIELD OF SEED COTTON OVER FIVE YEARS Treatment Seed cotton Ib/ac Non-irrigated 2291 30 perpendicular 3218 60 perpendicular 3491 90 perpendicular 3698 30 between row 3414 60 between row 3731 90 between row 3656 Significant yield increases were achieved for 3 out of the 5 years of this study with average yields over these 5 years as shown in Table 2. The average over all irrigation treatments for the 5 years was 1244 pounds of seed cotton per acre greater than the non- irrigated treatment. Subsurface drip irrigation (SDI) tape products and fertigation. A subsurface drip irrigation study initiated in 1998 was designed to compare five different drip irrigation tape prod- ucts with a fertigation component included. This study was installed in an area where continuous crops have been pro- duced for many years. Emitters were located 2 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 us- ing a single (conventional) surface applied sidedress versus multiple sidedress applications injected through the subsur- face drip irrigation system. A tape product was also used on the surface using a conventional fertilizer treatment. Fertility treatments are indicated in Table 3. In 1998 little difference between fertility treatments was ob- served. Sufficient rainfall occurred late in the growing season so that fertilizer in the upper layers of the soil was readily available. In 1999, extremely dry conditions in the upper layers of the soil pro- file made conventional applied fertilizer less available, resulting in yield reduction compared to fertilizer applied through the irriga- tion system. In 2001, initiation of fertigation through the tape was inadvertently delayed more than 2 weeks. Even though the fertigation schedule was modified to insure that all scheduled fer- tilizer was applied, the delay reduced fertigated yields. Yields in 13 w 0. z o 0 1: 0 0 uJ(I C?, 0 z 0 n. . . . .. . - I : : : : -::.:: I::::iil-::1~ I I:::::: :::::--- -: -:::: ::: :: :-::-il:)-i:i-i-i~ I -I::: :-: : ALABAMA AGRICULTURAL EXPERIMENT STATION Figure 2. Drip placement and irrigation scheduling. 0l1998 2938.9 3469.09 3680.61 3722.5 3614.64 3868.04 3446.06 E31999 1589.52 3024.07 3123.2 4053.38 3556 3929.82 4154.95 [32000 1583.24 3170.67 3660.72 3834.54 3391.61 3830.35 3747.63 032001 3464.56 3393.7 3560.19. 3580.09 3522.5 3647.1 3557.05 * 021879.223045 3429.30 3298.41 2986.37 3382.18 3373.81 P6RP DICULAR (T) vs BETWEEN ROWS (11) TABLE 3. FERTILITY TREATMENTS Irrigated Non-irrigated Fertigated Conventional Drip tape on surface 2 Preplant 75#N.+- 60#K* 75#N+ 60#K 75#N + 60#K 75# + 60#K Sidedress' 60#N +6# 60#N +T60#K* 60#N + .60#K 60#.N 'All sidedress was. applied -at early to, mid square for conventional and drip: tape treatments; the sidedress treatment w-as divided into eight equal applications for the fertigated treatments beginning at early 'to mid square. 2 The surface tape treatment was discontinued after 2000 because of damage and leaks caused by insects and other animals. 2002 were similar to previous years with little difference between fertilizer treatments but significant yield improvement over the non-irrigated treatment. Significant yield differences were observed each year between non-irrigated plots and tape plots with fertility treat- ments. Figures 3 and 4 illustrate yield results for 1998 through 2002 for conventional and fertigated treatments. To date only minimal differences- have been observed between the different drip irrigation tape products. Average yields for the 5 years are shown in Table 4. TABLE 43 FIVE YEAR AVERAGE YIELD OF* SEED Co-rroN Seed cotton -(lb/ac) Conventional Fertigated Not Irrigated 2073 Surface T-Tape 2 3545 T-Tape 3457 3511 Raintape 3499 3645 Netafllm 3501 3617 Eurotape .3510 3668 14 a.: 0. 0 w CD, CO z 0 4500- 4000- 3500- 3000- 2500 2000- 1500- 1000 - 500 - 0-1 2002 COlTON RESEARCH REPORT Figure 3. Drip tape comparison with conventional fertility program. ;4 5 0 0 ... .. .............. ...... 01-1998 C3 999 4000 C32000 i :1 [3200 7 3500 *2002 -_____________ 3000,1U 2500- 0 00 CO, ~1500 - 0l1998 031999 03200 0 0l2001 0 2002 NO SRFCE-T-TAPE RAINTAPE NErAFILM IRRIGATED TA PE 2448.33 3244.66 3561.51 3904.79 3633.58 1658.72 4013.85 3064.73 2770.22 3158.18 1561.43 3377.5 3723.42 .3689.79 3752.25 2949.91 3521.63 3742.64 .3454.37 1748.81 3411.37 3386.63 3505.78 TAPE PRODUCT Figure 4. Drip tape comparison: fertigation program. 4500 - 01998 4000 .01999 o2000 3500 02001 om*2002 w 3000 - z 2500 --- 0 ~2000 - CO) S1500 -- z 0 a. 1000 500 01998 m 1999 032000 032001_ IN 2002, 3543.25 3770.02 3699.4 3743.84 3956.67 4182.96 3844.01 4061.65 3550.46 3569.68 3684.98 3651.35 3175.72 3137.28 3315.04 3329.46 3329.70 3563.67 3542.29 3555.75 TAPE PRODUCT 15 3563.19 2921.56 3810.2 3704.8 3548.52 ALABAMA AGRICULTURAL EXPERIMENT STATION CONSERVATION TILLAGE AND POULTRY LITTER EFFECTS ON COTTON K. C. Reddy and E. Z. Nyakatawa The adoption of conservation tillage for cotton (Gossypium hirsutum L.) production in some counties of north Alabama has lagged behind that of other parts of the state. Poor emergence, reduced seedling growth, delayed maturity, and reduced yield are some of the problems which have been attributed to the slow adoption of conservation tillage sys- tems. A field experiment to study the effects of tillage (no till, mulch till, and conventional till), cropping system (cotton win- ter fallow without cover crop and cotton with winter rye ([Secale cereale L.] cover crop), and nitrogen source (poultry litter and ammonium nitrate) on growth and yield of cotton was initiated at the Tennessee Valley Research and Extension Center, Belle Mina, Alabama on a Decatur silt loam soil in 1996. The experi- mental design was a randomized complete block design with four replications. The winter rye cover crop, variety Oklon, was planted in fall and killed by Roundup herbicide (glyphosate) about 7days after flowering in spring. A no-till grain drill was used to plant the rye cover crop at 60 kg ha-' (See note at end of article for conversion factor to use for converting from metric to English measurement). Cotton variety Deltapine NuCotn 33B was planted in all plots at 16 kg ha-', using a no-till planter. During the season, a cultivator was used for controlling weeds in the conventional till system while spot applications of Roundup using a knapsack sprayer were used to control weeds in the no-till and mulch-till systems. Cotton lint yield under no till was 24, 7, 24, and 8% greater than that under conventional till in 1997, 1998, 2000, and 2001, respectively (see figure). Improved soil moisture conservation in no till plots was largely respon- sible for improved lint yields in this system. Cover cropping increased cotton lint yields by 6 to 12% compared to cotton winter fallow cropping in 2000 and 2001 (see figure). Poultry litter containing 100 kg N ha- I generally gave similar cotton lint yield to ammonium nitrate at the same rate whereas at 200 kg N ha-', lint yields were 25 to 38% significantly greater than those at 100 kg N ha-' in the form of ammonium nitrate or poultry litter. Soil moisture measurements in the top 7 cm of the soil taken during cotton seedling emergence showed a greater volumet- ric soil moisture content in no till plots compared to conven- tional till plots with or without poultry litter. Poultry litter im- proved soil water holding capacity which resulted in higher soil moisture content in no till and poultry litter plots during dry spells. Residues left at the surface and the mulch provided by poultry litter under no till reduced loss of soil moisture by evaporation which resulted in higher yields in no till and poul- try litter plots. In practical terms, no till, cover cropping, and surface application of poultry litter at 200 kg N ha-' into crop residues will be useful for soil moisture conservation in cotton production systems in the southeastern United States where erosion is a problem and abundant poultry litter is available. Note: To convert from metric to English measurement, multiply kg/ha times 0.893 to get pounds per acre. 16 2002 COTTON RESEARCH REPORT 17 Lint yield of cotton as influenced by conventional till (CT), mulch till (MT), and no till (NT) tillage systems; cotton winter fallow (CF) and cotton winter rye (CR) cropping systems; and ammonium nitrate (AN) and poultry litter (PL) sources of nitrogen at Belle Mina, Alabama, 1997 to 2001. (Letters show mean separation at 0.05 level of significance.) 2000 Tillage systems 1500 aC. a aa b 1000 *~500- 0- Niropigen steamnsd 1500-C CaO ac a a0......PL 500 U 200PL.:---:;: .... .... ...... :: ..........a E C a a b CR 500- 0- 199 198200 00 1997 19918--- 2000 2001l ALABAMA AGRICULTURAL EXPERIMENT STATION IRRIGATED COTTON MANAGEMENT WITH CONSERVATION TILLAGE D. W. Reeves, J. N. Shaw, L. Curtis, and C. Burmester Historically, dry weather during the critical fruiting period in the Tennessee Valley Region is common. During the critical fruiting period, from the last week of June to the second week of August, a minimum of one third of the days will be drought days (plant-available soil water is reduced to zero) in 50% of the years. In 3 years out of 10 a minimum of 65% percent of the days during this period will be drought days. For these soils, deep tillage under-the-row in fall, to reduce soil compaction and increase the volume of soil available for rooting and water storage, coupled with a cover crop to produce adequate resi- due for moisture conservation, can reduce the risks of drought- induced yield reductions. Irrigation technologies offer produc- ers reduced risks and increased profitability; however, man- agement of irrigation in conservation tillage systems has not been researched. This project was conducted in 2002 to evaluate irrigation management and tillage system interactions related to cotton yield and water relations. Tillage by irrigation regimes was im- posed at the Tennessee Valley Extension and Research Center in Belle Mina, Alabama. Treatments consisted of four tillage systems and four irrigation regimes in all possible combina- tions. Tillage systems included the following: (1) conventional tillage (fall chisel/disk, spring disk/level) without paratilling; (2) conventional tillage (fall chisel/disk, spring disk/level) Tillage trreatments with fall paratilling; (3) no till- age with rye cover crop with- Conventional tillage without pa out paratilling; and (4) no till- Conventional tillage with parati age with rye cover crop with No-tillage/cover crop without fall paratilling. Overhead No-tillage/cover crop with para sprinkler irrigation regimes in- Irrigation means 2 cluded the following: (1) 0 1Yield is measured in pounds gallons per minute (no irriga- 2 LSD (0.10) for irrigation mear tion); (2) 2 gallons per minute (1 inch every 9.4 days); (3) 4 gallons per minute (1 inch every 4.7 days); and (4) 6 gallons per minute (1 inch every 2.35 days). Cotton growth started slowly due to a wet spring with some unusually cold weather. Only irrigation affected lint yields, ginning percentage, and total cotton dry matter production (see table). There were no differences due to tillage, nor were there any tillage X irrigation interactions on these variables. Ginning percentage decreased with irrigation, averaging 40.1% with no irrigation and 37.1% when irrigated. Within irrigated treatments, there were no differences among rates. Lint yields and post-harvest total cotton dry matter (plant size) increased with irrigation rate to the 4 gallons per minute irrigation rate regime, averaged over all tillage treatments. Lint yields aver- aged 680, 932, 1024, and 994 pounds per acre for the 0, 2, 4, and 6 gallons per minute irrigation regimes, respectively. Although lint yields were not found to be affected by tillage or by the interaction of tillage and irrigation regimes, these types of stud- ies need to be conducted for a number of seasons in order to make valid conclusions and recommendations. Preliminary data indicate that tillage did impact soil water and plant water stress, but further statistical analysis is needed to evaluate these data. This study will continue through the 2003 season. OTTON LINT YIELD' FOR 2002 0 gpm 2 gpm 4 gpm 6 gpm Tillage means ratill 609 1011 1084 1053 939 ill 577 968 1017 936 875 paratill 758 856 991 1010 903 till 776 894 1006 976 913 680 932 1024 994 per acre. ns = 81 pounds per acre. 18 192002 COTFTON RESEARCH REPORT NUTRIENT MOVEMENT UNDER LONG-TERM BROILER LITTER FERTILIZATION C. C. Mitchell and W. C. Birdsong Alabama produces almost three times more poultry broiler litter (by weight) as commercial fertilizers used. In regions of intensive poultry production, most broiler litter is over applied to pastures and hayfields creating potential nutrient enrich- ment of surface and ground waters. Row crop farmers have concerns about using broiler litter on their crops, especially cotton. In 1990 and 1991, experiments were begun to address some of these concerns. Experiments began in 1990 at the Tennes- see Valley Research and Extension Center, Belle Mina, Ala- bama, and in 1991 at the E.V. Smith Research Center, Shorter, Alabama, with 11 treatments replicated four times in a random- ized block design (see table). Soil at theTennessee Valley site is a Decatur silt loam. The experiment at this site was discontin- ued after 3 years. Soil at the E.V. Smith site is a Norfolk fine sandy loam. This site has been continued from 1991 through 2002. Today, it is one of the oldest, continuous experiments in the United States with poultry manure on crops. Plot size at both sites was 25 feet long and 24 feet wide, which accommodated eight, 36-inch rows of cotton or corn. All broiler litter was broadcast just prior to planting at a rate based upon the total N concentration in the litter. Ammonium nitrate rate was split with half applied at planting and half applied as a sidedress. All treatments except the broiler litter treatments received 27 pounds per acre of P and 50 pounds per acre of K as concentrated superphosphate and muriate of potash, respec- tively, at planting. The sites were in conventionally tilled cotton through 1993 (moldboard plow, disk, field cultivate, and cultivate to control weeds; winter fallow). Nutrients were incorporated just prior to planting under conventional tillage. In 1994, treatments at the E.V. Smith site were slightly modified to include residual broiler litter treatments. The experiment was planted to conser- vation-tilled corn from 1994 to 1997 (winter rye planted as a cover crop; nutrients surface applied just prior to planting into rye residue after spraying with glyphosate; in-row subsoiled to 14 inches every springjust prior to planting; no cultivation). From 1998 through 2002, the experiment has been in conserva- tion tilled cotton (see table). Three years of broiler litter application in the Tennessee Valley and 11 years application in a Coastal Plain soil dramati- cally increased extractable P, K, Ca, Mg, Zn, and Cu in surface soils in proportion to that applied in the broiler litter (Figure 1). There was also a slight but significant accumulation of surface soil organic C and N after 11 years in Central Alabama at the highest broiler litter rate (240 pounds N per acre as broiler litter or approximately 4 tons of broiler litter per acre every 2 years) (Figure 2). When broiler litter is used as a source of N, soil pH is maintained or slightly increased depending upon the rate used (data not shown). Rapid nitrate leaching in these soils results in generally low measurable levels of soil nitrate-N. The preside dress soil nitrate test does not predict crop response to sidedress N regardless of N source at planting. TREATMENTS USED IN EXPERIMENTS WITH BROILER LITTER ON COTTON AND CORN AT Two LOCATIONS Both locations' Central Alabama location only 2 Source of N N rate Growth Source of N N rate Other factors lb/ac regulator 3 lb/ac None 0 no None 0 Am. nitrate 60 no Am. nitrate 60 Am. nitrate 60 yes Am. nitrate 120 Am. nitrate 120 no Am. nitrate 180 Am. nitrate 120 yes Am. nitrate 240 Broiler litter 120 no Broiler litter 120 Broiler litter 120 yes Broiler litter 120 Residual 4 Broiler litter 180 no Broiler litter 180 Broiler litter 180 yes Broiler litter 180 Residual 4 Broiler litter 240 no Broiler litter 240 Broiler litter 240 yes Broiler litter 240 Residual 4 Cotton-conventional tillage, 1990-1993. 2 Corn-conservation tillage, 1994-1997; Cotton-conservation tillage, 1998-2002. 3 Pix (mepiquat chloride) applied at rate of 8 oz/ac in multiple applications. 4 Broiler litter and residual plots were alternated each year so that each year there was a residual treatment which did not receive an N source. ALABAMA AGRICULTURAL EXPERIMENT STATION Figure 1. Mehlich-1 extractable K with depth at the E.V. Smith location in central Alabama. '9K, mg/kg K, mg/ha 40 _&0 120 t mg/k4 -e--- N ~Hi 2001 Figure 2. After 11 years at E.V. Smith with 32 tons per acre of broiler litter applied, significant increases in both total N and C were found in the upper 20 cm of the soil. Total N, glkg Total C, glkg 0.0 0.1 0.2 0.3 0.4 0.5 0 2 4 6 8 iC 20 40 Depth, c m 60 80 4 Check -sAN @ 120 lb N/a y-BL @240 lb N/a M/a a 100 120 20 K, mg./k 0 20 40 60 0) 80 100 120 h i b 4u It) c. I t 1993 1995 %-If 2002 CorroN RESEARCH REPORT NEW CHANGES PRODUCE RECORD YIELDS ON OLD ROTATION C. C. Mitchell, D. Delaney, and D. W. Reeves The Old Rotation experiment (circa 1896) on the campus of Auburn University is the oldest, continuous cotton experi- ment in the world. Since the centennial cropping year of the Old Rotation (1995), major technological modifications have been imple- mented in managing this experiment. These include switching to genetically modified crops, almost complete elimination of insecticide use, drastically reducing herbicide use, and switch- ing to conservation tillage instead of conventional moldboard plowing and cultivation. In 2002, another dramatic change is being monitored in the old experiment. Irrigation has been in- stalled so that half of each plot can now be irrigated. This report will highlight yields and observations made during these transition years. The site is at the junction of the Piedmont Plateau and Gulf Coastal Plain soil physiographic regions. The soil is iden- tified as a Pacolet sandy loam. There are 13 plots on 1 acre of land. Each plot is 136 feet long by 21.5 feet wide with a 3-foot alley between each plot and comprise seven cropping systems (Table 1). All plots were managed with conventional tillage (mold- board plow, flatbed disk or chisel, field cultivate or harrow, and cultivation for weed control) from 1896 through 1996. In 1997, all plots were switched to conservation tillage (spring paratill under the row and plant using no till planter; no mechanical cultivation). A goal was to establish reseeding crimson clover in those plots planted to winter legumes. Since switching to genetically modified crops in 1996 and conservation tillage in 1997, record yields of all crops have been produced on the Old Rotation (Table 1). A record three bales cotton per acre (1600 pounds lint) was produced in 2001 on a plot which has never received anything but legume N (plot 8). In 1999, a record corn grain yield of 236 bushels per acre was produced on the 3-year rotation with only legume N. In 1997, just prior to conversion to conservation tillage, additional soil physical and chemical measurements were taken to serve as a benchmark for future comparisons (Table 2). As crop rotation increased and more biomass was returned to the soil in the form of crop residue, soil water holding capacity, hydraulic conductivity (Ksat), respiration, total C, total N, cat- ion exchange capacity (CEC), and water-stable aggregates have increased. All these indicate improvements in soil quality. For more information about the Old Rotation and long- term yield records, visit the Web site at http:// www.ag.auburn.edu/dept/ay/cotton.htm. TABLE 1. RECORD NONIRRIGATED YIELDS ON THE OLD ROTATION Crop Rank Year Plot Record yield Cotton 1 2001*1 8 1600 lb lint/acre 2 1994 3 1490 3 1993 9 1270 Corn 1 1999* 11 236 bu/acre 2 2001* 5 193 3 1997* 5 148 Wheat (1961-present) 1 2001* 10 94 bu/acre 2 2000* 11 81 3 1999* 12 79 Oat (beforel960) 1 1958 - 109 2 1937 - 97 3 1956 - 87 Rye (1978-present) 1 1981 - 55 2 1988 - 48 3 1979 - 40 Soybean (1957-present) 1 1996 12 67 bu/acre 2 1992 - 61 3 1983 - 55 Winter legume 1 1981 11 7250 Ib dry matter/acre 2 2000* 8 6480 3 1999* 3 6410 1* indicates conservation tillage since 1997. 21 ALABAMA AGRICULTURAL EXPERIMENT STATION TABLE 2. SELECTED SOIL PHYSICAL AND CHEMICAL MEASUREMENTS MADE ON TREATMENTS FROM THE OLD ROTATION IN 1997 BEFORE CONVERSION TO CONSERVATION TILLAGE Treatments Bulk Soil Ksa t Soil Total C Total N C.E.C. Water stable density water respiration aggregates g/cmn % in/min lb/C/ac/day % cmol/kg % Continuous cotton: No N/no legumes 1.66 7.69 c 0.37 22 b 0.50 d 0.02 c 3.1 c 49.8 b + winter legumes 1.66 7.47 b 0.43 44 ab 0.84 c 0.04 ab 4.3 b 52.2 b +120 Ib N/acre 1.73 9.40 bc 0.04 36 ab 0.87 c 0.04 abc 5.6 a 34.7 c Two-yr rotation: + winter legumes 1.68 10.11 ab 0.57 60 a 0.85 c 0.05 ab 4.6 b 53.2 b +legumes/+120 lb N/acre 1.62 11.67 a 0.33 45 ab 1.09 b 0.06 a 5.4 a 48.9 b Three-yr rotation 1.65 11.47 a 1.22 60 a 1.27 a 0.05 ab 5.5 a 64.1 a 22 2002 CorroN RESEARCH REPORT INSE CTCI[DES EFFECTS OF A WIDE RANGE OF INSECTICIDES ON TARNISHED PLANT BUGS IN COTTON Barry L. Freeman This trial was conducted on the Tennessee Valley Re- search and Extension Center in Belle Mina, Alabama, to test the effectiveness of a variety of insecticides on tarnished plant bugs. The test was conducted as a nonreplicated large strip trial to minimize the effects of migration. Plots were 100 feet long by eight rows wide and were under irrigation. Treatments were applied on July 10, 2002. Post-treatment 6-foot drop-cloth samples were conducted on July 15, July 18, and July 22 to estimate plant bug populations. Five samples per plot on each sample date were desired, but inclement weather forced this number to be abbreviated to three in all treatments on July 22. Pinhead square retention was determined on the above dates by examining 50 pinhead squares in each plot for plant bug damage. Seed cotton yields were determined by harvesting and weighing the four center rows from each plot on October 2. Pinhead square retention remained above 80% and plant bug populations were low or moderate during the latter half of June. On July 1 the pinhead square retention in the test area was 80%, approximately 33 plant bug nymphs per 100 row feet were present, and adult plant bugs were common. On July 8 the pinhead square retention was down to 74% and the nymphal plant bug population averaged 108 per 100 row feet. Though the tarnished plant bug was predominant, some adult and nymphal garden fleahoppers were also present during this trial. Average plant bug populations for the entire post-treat- ment period are shown in Table 1. Eight of the insecticide treat- ments (Karate Z, Intruder plus MSO, Intruder plus COC, F1785, Bidrin, Centric 0.0635, Orthene, and Centric 0.0475) reduced the overall post-treatment plant bug population by 65% or more (Table 1). The Intruder treatment without additives reduced the overall population by only 53.42%, but the average ending population on July 22 was acceptable (Table 1). In addition to the above list of treatments, Vydate plus Asana, Intruder, Asana, and V-10112 0.088 all provided an aver- age pinhead square retention level above 80% during the post- treatment period (Table 2). The only treatments at the end of the sample period with an average square retention level of 85% or above were Karate Z, F 0570, Orthene, Intruder plus COC, and Centric 0.0635. Pinhead square retention becomes unreliable as a predictor of plant bug activity as terminal growth slows. This usually occurs during mid to late July, which coin- cides with the period of this trial. Nevertheless, the pinhead square retention data from this test generally reflect anticipated product performance. Cotton yields are reported in Table 3, but this test was run as a large strip trial and is unreplicated. All but three treat- TABLE 1. NUMBERS OF PLANT BUGS PER 100 FEET OF Row Plant bugs % change Treatment July 15 July 18 July 22 Average from control Karate Z (0.025 lb a.i./ac) 23 33 22 26 -88 Intruder + MSO (0.05 lb a.i./ac + 1 pt/ac) 30 43 78 50 -78 Intruder + COC (0.05 lb a.i./ac + 1 pt/ac) 37 57 61 52 -77 F1785 (0.053 Ib a.i./ac) 67 78 17 54 -76 Bidrin (0.33 lb a.i./ac) 37 107 22 55 -75 Centric (0.0635 Ib a.i./ac) 63 87 39 63 -72 Orthene (0.5 lb a.i./ac) 60 100 50 70 -69 Centric (0.0475 lb a.i./ac) 80 107 44 77 -66 F 0570 (0.018 lb a.i./ac) 50 130 94 91 -59 Steward (0.11 lb a.i./ac) 88 128 89 102 -55 Intruder (0.05 lb a.i./ac) 137 133 44 105 -53 Vydate (0.33 Ib a.i./ac) 93 143 122 119 -47 V-10112 (0.088 Ib a.i./ac) 83 150 139 124 -45 Asana (0.04 lb a.i./ac) 183 128 128 146 -35 Vydate + Asana (0.25 + 0.036 Ib a.i./ac) 73 280 94 149 -34 Trimax (0.047 Ib a.i./ac) 143 200 122 155 -31 V-10112 (0.044 lb a.i./ac) 196 183 128 169 -25 Control 258 278 139 225 - 23 ALABAMA AGRICULTURAL EXPERIMENT STATION TABLE 2. PERCENT PINHEAD SQUARE RETENTION Pinhead square retention % change Treatment July 15 July 18 July 22 Average from control Orthene (0.5 Ib a.i./ac) 96.0 92 92 93.33 +41.05 F 0570 (0.018 Ib a.i./ac) 88.0 92 94 91.33 +38.02 Bidrin (0.33 Ib a.i./ac) 92.0 98 84 91.33 +38.02 Centric (0.0635 Ib a.i./ac) 92.0 94 86 90.67 +37.03 Karate Z (0.025 Ib a.i./ac) 80.0 90 96 88.67 +34.00 Intruder + MSO (0.05 Ib a.i./ac+ 1 pt/ac) 94.0 82 84 86.67 +30.98 Vydate + Asana (0.25 + 0.036 Ib a.i./ac) 92.0 84 80 85.33 +28.96 Intruder + COC (0.05 lb a.i./ac + 1 pt/ac) 84.0 80 90 84.67 +27.96 Centric (0.0475 lb a.i./ac) 76.0 88 78 80.67 +21.91 Intruder (0.05 Ib a.i./ac) 88.0 84 70 80.67 +21.91 V-10112 (0.088 Ib a.i./ac) 97.5 74 70 80.50 +21.66 Asana (0.04 lb a.i./ac) 88.0 72 80 80.00 +20.90 Trimax (0.047 lb a.i./ac) 84.0 76 76 78.67 +18.89 Vydate (0.33 Ib a.i./ac) 86.0 86 64 78.67 +18.89 F 1785 (0.053 Ib a.i./ac) 80.0 72 76 76.00 +14.86 V-10112 (0.044 lb a.i./ac) 87.5 58 66 70.50 + 6.54 Steward (0.11 lb a.i./ac) 78.0 72 60 70.00 + 5.79 Control 72.5 70 56 66.17 - ments, the V-10112 product and one of the Centric treatments, outyielded the untreated control (Table 3). The highest yield- ing treatments were two of the Intruder treatments, Karate Z, Trimax, F 1785, and and a Centric treatment, and they out performed the control by 7.44 to 13.8% (Table 3). This trial demonstrates the difficulty of controlling an imbedded population of plant bugs on a large plant. Only one product, Karate Z, provided above 80% control (Table 1). Nev- ertheless, the old standards, Bidrin and Orthene, performed decently as did Centric, Intruder, and F 1785. The V- 10112 com- pound was a disappointment. TABLE 3. COTTON YIELDS AS POUNDS OF SEED COTTON PER ACRE Seed cotton % change Treatment per acre from control Intruder + COC 3504 +13.80 (0.05 lb a.i./ac + 1 pt/ac) Karate Z (0.025 lb a.i./ac) 3472 +12.76 Trimax (0.047 lb a.i./ac) 3440 +11.72 Intruder (0.05 lb a.i./ac) 3341 +8.51 F1785 (0.053 lb a.i./ac) 3341 +8.51 Centric (0.0475 lb a.i./ac) 3308 +7.44 F0570 (0.018 lb a.i./ac) 3242 +5.29 Orthene (0.5 lb a.i./ac) 3242 +5.29 Steward (0.11 lb a.i./ac) 3242 +5.29 Bidrin (0.33 lb a.i./ac) 3210 +4.25 Intruder + MSO 3177 +3.18 (0.05 Ib a.i./ac + 1 pt/ac) Vydate + Asana 3177 +3.18 (0.25 +0.036 Ib a.i./ac) Vydate (0.33 Ib a.i./ac) 3177 +3.18 Asana (0.04 Ib a.i./ac) 3144 +2.11 Control 3079 - Centric (0.0635 lb a.i./ac) 3013 -2.14 V-10112 (0.044 Ib a.i./ac) 2882 -6.40 V-10112 (0.088 Ib a.i./ac) 2817 -8.51 24 2002 CorroN RESEARCH REPORT CONTROL OF THRIPS ON SEEDLING Barry L. Freeman This test was designed to compare seed and in-furrow treatments with and without foliar insecticides for thrips con- trol. It was located on the Tennessee Valley Research and Ex- tension Center in Belle Mina, Alabama, and was planted on April 23, 2002. Plots were four rows wide by 25 feet long and were replicated four times each. Foliar applications were made on May 15. Thrips were sampled on May 7, May 15, May 22, May 29, and June 4 by rinsing five plants from each plot in ethyl alco- hol. Each sample was then filtered and the resulting thrips counted under a dissecting microscope. Adult and immature thrips were tallied separately. An earliness evaluation was made on July 9 and July 11 by counting all white blooms in the center two rows of each plot. Seed cotton yields were determined by harvesting the center two rows of each plot on September 24. All treatments except the control kept thrips populations at acceptable levels through May 22 (Table 1). Thrips repro- COTTON duction was becoming evident in the Gaucho and Cruiser treat- ments on May 29 and by June 4 all treatments except the Temik plus Orthene contained more than one thrips larva per plant (Table 1). The Orthene overspray reduced the thrips popula- tion for all three at-planting insecticides (Table 1). The control plots contained fewer white blooms than the insecticide treatments on July 9 and July 11 (Table 2). The in- secticide treatments with the fewest numbers of blooms were the low rate of Temik and Gaucho treatments (Table 2). The neonicitinoid treatments outyielded other treatments and the addition of Orthene improved both the Gaucho and Cruiser yields (Table 3). Rainfall totaling 2.68 inches fell on May 3 and May 4 and may have had some impact on the perfor- mance of Temik, but the thrips control in these plots does not bear that out. These data support past experiences, which indi- cate that the neonicitinoid seed treatments often yield above expectations based on thrips populations. TABLE 1, PART A. AVERAGE NUMBER OF THRIPS PER FIVE PLANTS, 2002 -May 7- -- May 15- -May 22- -May 29 Treatments Adult Larva Adult Larva Adult Larva Adult Larva Temik 0.53 Ib a.i./ac 0.75 0.00 0.00 0.75 0.25 0.50 0.50 1.25 + Orthene 0.2 Ib a.i./ac Cruiser 4.8 oz a.i./cwt. seed 0.00 0.00 1.00 0.25 0.25 0.00 0.75 1.00 + Orthene 0.2 lb a.i./ac Gaucho 5 oz a.i./cwt. seed 0.50 0.00 0.50 1.50 0.00 0.25 1.50 0.25 + Orthene 0.2 lb a.i./ac Temik 0.75 lb a.i./ac 0.50 0.00 0.50 0.75 1.00 0.75 1.50 1.25 Cruiser 4.8 oz a.i./cwt. seed 0.00 0.00 0.50 0.25 1.50 0.25 3.00 3.25 Temik 0.53 Ib a.i./ac 0.50 0.00 0.50 1.75 2.00 1.00 1.00 1.75 Gaucho 5.0 oz a.i./cwt. seed 2.25 0.00 0.50 0.00 3.25 1.50 2.25 3.75 Untreated control 7.75 0.00 0.25 8.20 1.00 15.00 2.50 13.75 TABLE 1, PART B. AVERAGE NUMBER OF THRIPS PER FIVE PLANTS, 2002 June 6- Seasonal average- % change Treatments Adult Larva Adult Larva Total from control Temik 0.53 Ib a.i./ac 6.25 3.00 1.55 1.10 2.65 -81.77 + Orthene 0.2 Ib a.i./ac Cruiser 4.8 oz a.i./cwt. seed 9.25 5.00 2.25 1.25 3.50 -75.93 + Orthene 0.2 Ib a.i./ac Gaucho 5 oz a.i./cwt. seed 6.00 7.75 1.70 1.95 3.65 -74.90 + Orthene 0.2 Ib a.i./ac Temik 0.75 Ib a.i./ac 7.00 10.75 2.10 2.70 4.80 -66.99 Cruiser 4.8 oz a.i./cwt. seed 5.50 14.25 2.10 3.60 5.70 -60.80 Temik 0.53 Ib a.i./ac 5.00 17.00 1.80 4.30 6.10 -58.05 Gaucho 5.0 oz a.i./cwt. seed 6.00 15.75 2.85 4.20 7.05 -51.51 Untreated control 8.00 16.25 3.90 10.64 14.54 - 25 TABLE 2. AVERAGE NUMBER OF WHITE BLOOMS PER 100 Row FEET, 2002 July 9 and % change Treatment July 9 July 11 Nov. 2 from control Gaucho 5 oz a.i./cwt. seed 2.75 20.63 26.13 +81.71 + Orthene 0.2 Ib a.i./ac Cruiser 4.8 oz a.i./cwt. seed 2.38 22.38 24.76 +72.18 Cruiser 4.8 oz a.i./cwt. seed 3.38 20.88 24.26 +68.71 + Orthene 0.2 Ib a.i./ac Temik 0.53 Ib a.i./ac 3.13 17.75 20.88 +45.20 + Orthene 0.2 Ib a.i./ac Temik 0.75 Ib a.i./ac 2.50 18.13 20.63 +43.46 Gaucho 5.0 oz a.i./cwt. seed 2.75 16.13 18.88 +31.29 Temik 0.53 Ib a.i./ac 1.89 14.13 16.02 +11.40 Untreated control 1.13 13.25 14.38 - TABLE 3. COTTON YIELDS IN POUNDS OF SEED COTTON PER ACRE Treatment Yield % change from control Gaucho 5 oz a.i./cwt. seed 3300 +16.77 + Orthene 0.2 lb a.i./ac Cruiser 4.8 oz a.i./cwt. seed 3189 +12.85 + Orthene 0.2 lb a.i./ac Cruiser 4.8 oz a.i./cwt. seed 3136 +10.97 Gaucho 5.0 oz a.i./cwt. seed 3019 +6.83 Temik 0.53 lb a.i./ac 2957 +4.64 Temik 0.53 lb a.i./ac 2940 +4.03 + Orthene 0.2 Ib a.i./ac Untreated control 2826 - Temik 0.75 lb a.i./ac 2800 -0.92 EVALUATION OF SEED TREATMENTS FOR THRIPS CONTROL IN THE WIREGRASS AREA James R. Weeks and William Birdsong This study, which compared seed and in-furrow treatments for thrips control in Bt and non-Bt cotton, was conducted at the Wiregrass Research and Extension Center in Headland, Ala- bama. The soil type is a Dothan sandy loam. Fertility, weed management, and irrigation for the study area were according to Alabama Cooperative Extension System (ACES) recommen- dations. Cotton cultivars FiberMax 989 RR and FiberMax 989 BR were planted on April 22, 2002 with a four-row John Deere vacuum planter. Seed treatments of Gaucho or Cruiser were treated from a common bag of each cultivar. Temik 15G or Thimet 20G were applied in-furrow at planting with the planter applica- tor. Foliar sprays of Karate Z or Orthene 97AG were applied on May 3, 2002. Treatments were arranged in a randomized com- plete block design with four replications. Each plot consisted of four 36-inch rows, 30 feet long. A treatment list with materials and rates is listed in Table 1. Stand counts (emerged seedlings) in one row of each plot were made on May 3, 2002. Whole plot subjective thrips dam- age ratings were made on May 14 and May 30. All plots were treated for stink bugs on August 8, 2002 with Karate at the rate of 0.02 pound active ingredient per acre. Plots were scouted weekly for insect pests according to ACES guidelines and thresholds for treatment decisions were followed. The two middle rows of each plot were harvested with a one-row mecha- nized picker on September 18, 2002. Although a few Heliothine eggs and larvae were found on several occasions, thresholds for treatment were never ex- ceeded in the Bt(BR) or non-Bt(RR) treatments. Because of 26 ALABAMA AGRICULTURAL ExPERIMENT STATION 2002 ColTON RESEARCH REPORT 27 defoliation problems and poor boll opening, a second picking was planned. Rainy weather in October and subsequent boll rot prevented a second harvest. Late season weather condi- tions created problems with boll rot and regrowth which ap- pear to have affected treatment yields. Much of the earliness that good thrips control promoted was lost due to the boll rot of the early-set fruit. Yields from the first harvest indicate that treatments of the FiberMax BR out yielded the FiberMax RR cultivar by 231 pounds of lint cotton (Table 2). The seed treat- ments of Cruiser and Cruiser plus foliar sprays had comparable yields to that of Temik 15G in-furrow treatments. However, early season thrips damage ratings indicated that Temik 15G treatments had less seedling cotton damage than did the Gau- cho or Cruiser seed treatments. Cruiser and Gaucho brand insecticides applied to cotton seed afford moderate to good early season thrips control under southeast Alabama conditions. For consistency comparable to Temik 15G in-furrow treatments, a cotton grower should be pre- pared to make an additional foliar application in the 2- to 4-leaf stage when thrips populations are especially heavy and/or grow- ing conditions are unfavorable for cotton. Even though the cotton in the study never exceeded thresh- old for bollworms, the treatments with the cultivar including the BollGard gene (BR) had higher yields than the treatments with the cultivar without the BollGard gene (RR). Low level infesta- tions of bollworms, tobacco budworms, and late season fall armyworms apparently were causing enough damage season long to account for the yield increase due to BollGard. TABLE 1. AVERAGES OF TREATMENTS FOR THRIPS CONTROL 1 Treatment 2 Cultivar Stand TDR 1 TDR 2 Lint yield no/30 ft May 14 May 30 lbs/ac Untreated control FM 989 RR 77.75 ab 8.62 a 9.15 a 985 abcd Untreated control FM 989 BR 63.75 cdef 8.78 a 8.88 a 1169 ab Cruiser seed treatment FM 989 RR 61.50 defg 5.05 de 5.95 cd 1137 ab Cruiser seed treatment FM 989 BR 53.25 ghi 5.18 cde 5.33 def 1123 abc Cruiser seed treatment FM 989 RR 71.75 bc 4.07 i 4.18 gh 1038 abcd + Karate 1 oz/ac (FSP at 1-2 TL) Cruiser seed treatment FM 989 BR 47.75 i 4.65 efgh 4.75 fgh 1113 abc +Karate 1 oz/ac (FSP at 1-2 TL) Temik 15g 3.5 lb/a (InF) FM 989 RR 77.50 ab 4.15 hi 3.98 h 1169 ab Temik 15g 3.5 lb/a (InF) FM 989 BR 55.50 fghi 4.22 ghi 4.38 gh 953 cd Temik 15g 5 lb/ac (InF) FM 989 RR 81.75 a 2.75 j 2.80 i 1062 abc Temik 15g 5 lb/ac (InF) FM 989 BR 70.00 bcd 2.55 j 2.78 i 1116 abc Gaucho seed treatment FM 989 RR 56.25 fghi 5.68 c 6.05 bcd 818 d Gaucho seed treatment FM 989 BR 51.00 hi 5.33 cd 5.88 cde 1096 abc Gaucho seed treatment FM 989 RR 63.00 cdef 4.78 ef 4.58 fgh 1043 abcd +Karate 1 oz/ac (FSP at 1-2 TL) Gaucho seed treatment FM 989 BR 58.25 efghi 4.83 def 4.98 efg 1084 abc +Karate 1 oz/ac (FSP at 1-2 TL) Cruiser seed treatment) FM 989 RR 66.50 cde 4.43 fghi 4.53 fgh 1002 abcd +Orthene 97AG 4 oz/ac (FSP at 1-2 TL) Cruiser seed treatment) FM 989 BR 50.50 hi 4.78 ef 5.35 def 1062 abc +Orthene 97AG 4 oz/ac (FSP at 1-2 TL) Gaucho seed treatment FM 989 RR 56.00 fghi 4.70 efg 4.53 fgh 1014 abcd +Orthene 97AG 4 oz/ac (FSP at 1-2 TL) Gaucho seed treatment ) FM 989 BR 59.75 efghi 4.65 efgh 4.13 gh 1164 ab +Orthene 97AG 4 oz/ac (FSP at 1-2 TL) Thimet 20g 5 Ib/ac (InF) FM 989 RR 70.00 bcd 7.00 b 6.35 bc 897 cd Thimet 20g 5 Ib/ac (InF) FM 989 BR 64.00 cdef 6.78 b 6.90 b 1212 a 1 Data subjected to ANOVA. Mean separation within columns was according to Fisher's protected LSD test at 0.05 level. 2 FSP = foliar spray; TL = true leaf; InF = in furrow application. 3 TDR = thrips damage rating. Based on a 0-10 visual damage of each plot where 0 = no damage and 10 = dead plants. TABLE 2. CULTIVAR FIBERMAX 989 RR VERSUS FIBERMAX 989 BR Cultivar Stand TDR 11 TDR 2 Lint yield Yield lbs/ac FiberMax 989 RR 68.20 a 5.12 a 5.21 a 1016.64 b 2541.61 b FiberMax 989 BR 57.38 b 5.17 a 5.33 a 1109.33 a 2773.32 a TDR = thrips damage rating. Based on a 0-10 visual damage of each plot where 0 = no damage and 10 = dead plants. 2002COTTONRESEARCHREPORT 27 EVALUATION OF NEW INSECTICIDE CHEMISTRY AND BIOTECHNOLOGY Ron H. Smith A test was conducted for tarnished plant bug/stink bug Steward and Denim did not give acceptable control when used control and beneficial insect selectivity in 2002 comparing the alone. newer labeled chemistry to existing standard insecticides. Evalu- The most effective treatments for stink bugs (southern ations were made at 1, 4, and 7 days post treatment (DAT). green) were Trimax plus Bidrin (0.03 + 0.33 pound active ingre- Twenty-five treatments were made with single insecticides, dient), Centric, Orthene, Bidrin, Intruder plus MSO, Karate Z, tank mixtures, or additives (Table 1). Most treatments gave fair Vydate, and Assail (Table 2). The least effective treatments to good suppression of plant bugs. Karate Z, Orthene, and were Denim, Steward, Novaluron, Trimax, Intruder, and Intruder Vydate were the best three treatments in the test. The least plus COC. Centric (0.063 pound active ingredient) outperformed effective treatments were Novaluron, Intruder plus MSO or the othef newer chemistries-Intruder, Assail, or Trimax-when Decis, and Trimax plus Bidrin (0.03 + 0.25 pound active ingredi- each was used alone. All pyrethroids in this test were near the ent per acre). Some treatments showed good initial knockdown middle of the 25 treatments in effectiveness against the stink bug. at 1 DAT but a lack of residual control at 7 DAT. Other products The selectivity of all treatments towards the beneficial showed less knockdown but good residual control. Centric species (big-eyed bugs, pirate bugs, and lady beetles) was and Trimax showed better activity at higher rates. The perfor- measured. Of the newer chemistry, Intruder (Assail) is some- mance of Intruder for plant bugs was aided by the addition of a what selective on the big-eyed bug species but quite harsh on crop oil concentrate (COC) but not by a silicon surfactant (MSO). pirate bugs and lady beetles. Trimax, alone or in combination, TABLE 1. NUMBER OF TARNISHED PLANT BUGS PER 100 Row FEET July 12 -July 15 July 18 -- - Average Treatment (lb ai/ac) Nymphs Adults Total Nymphs Adults Total Nymphs Adults Total Nymphs Adults Total Karate Z (0.034) 8.3 0.0 8.3 0.0 Orthene (0.5) 8.3 0.0 8.3 0.0 Vydate (0.33) 16.7 0.0 16.7 0.0 Intruder + COC (0.05) 16.7 0.0 16.7 0.0 Leverage (0.077) 8.3 0.0 8.3 8.3 Vydate + Asana 0.0 0.0 0.0 0.0 ( 0.25 + 0.36) Centric + Karate Z 16.7 0.0 16.7 0.0 (0.023 + 0.02) Bidrin (0.4) 8.3 0.0 8.3 0.0 Centric (0.063) 0.0 0.0 0.0 8.3 Steward + Vydate 0.0 0.0 0.0 0.0 (0.09 + 0.25) Trimax (0.047) 16.7 0.0 16.7 0.0 Assail (0.075) 0.0 8.3 8.3 0.0 Trmadrin 8.3 16.7 25.0 0.0 (0.03 + 0.33) F 0570 (0.018) 16.7 0.0 16.7 0.0 Intruder (0.05) 16.7 8.3 25.0 16.7 Trimax (0.03) 25.0 0.0 25.0 8.3 Novaluron (0.045) 25.0 0.0 25.0 0.0 Centric (0.047) 33.3 0.0 33.3 0.0 Steward (0.11) 8.3 0.0 8.3 0.0 Denim (0.01) 8.3 0.0 8.3 16.7 Intruder + Decis 16.7 0.0 16.7 16.7 (0.036 + 0.023) Novaluron (0.068) 33.3 16.7 50.0 0.0 Trimax + Bidrin 25.0 0.0 25.0 41.7 (0.03 + 0.25) Novaluron (0.094) 50.0 16.7 66.7 16.7 Untreated 25.0 8.3 33.3 25.0 Intruder + MSO (0.05) 16.7 0.0 16.7 8.3 Untreated 66.7 16.7 83.3 25.0 Untreated 25.0 16.7 41.7 16.7 0.0 0.0 5.0 0.0 5.0 4.4 0.0 0.0 8.3 0.0 8.3 5.6 0.0 0.0 0.0 0.0 0.0 5.6 0.0 0.0 8.3 0.0 8.3 8.3 0.0 8.3 8.3 0.0 8.3 8.3 0.0 0.0 25.0 0.0 25.0 8.3 0.0 0.0 5.0 5.0 10.0 7.2 0.0 0.0 13.3 5.0 18.3 7.2 0.0 8.3 21.7 0.0 21.7 10.0 0.0 0.0 21.7 8.3 30.0 7.2 0.0 0.0 13.3 0.0 13.3 10.0 8.3 8.3 21.7 0.0 21.7 7.2 8.3 8.3 5.0 0.0 5.0 4.4 8.3 8.3 13.3 5.0 18.3 10.0 0.0 16.7 5.0 0.0 5.0 12.8 8.3 16.7 5.0 0.0 5.0 12.8 0.0 0.0 21.7 0.0 21.7 15.6 0.0 0.0 16.7 0.0 16.7 16.7 0.0 0.0 41.7 5.0 46.7 16.7 0.0 16.7 38.3 0.0 38.3 21.1 0.0 16.7 33.3 13.3 46.7 22.2 0.0 0.0 25.0 5.0 30.0 19.4 8.3 50.0 13.3 0.0 13.3 26.7 8.3 25.0 8.3 0.0 8.3 25.0 0.0 25.0 41.7 8.3 50.0 30.6 16.7 25.0 66.7 16.7 83.3 30.6 0.0 25.0 33.3 5.0 38.3 41.7 0.0 16.7 100.0 8.3 108.3 47.2 0.0 4.4 0.0 5.6 0.0 5.6 0.0 8.3 0.0 8.3 0.0 8.3 1.7 8.9 1.7 8.9 0.0 10.0 2.8 10.0 0.0 10.0 5.6 12.8 8.3 12.8 4.4 14.4 2.8 15.6 2.8 15.6 0.0 15.6 0.0 16.7 1.7 18.3 0.0 21.1 4.4 26.7 7.2 26.7 2.8 29.4 8.3 33.3 5.6 36.1 11.1 41.7 7.2 48.9 8.3 55.6 r I~ rml 1 1 1 ~ YY ~I ~ \V VVII ~ ~ -I- ALABAMA AGRICULTURAL ExPERIMENT STATION 28 was not very selective on big-eyed bugs or pirate bugs but nificantly fewer larvae and less damage than the untreated plots showed moderate selectivity against lady beetles. Centric on the peak observation dates of August 5 and August 12. showed some selectivity towards big-eyed bugs, pirate bugs, When the seasonal averages were examined, all treatments had and lady beetles. Vydate was selective against big-eyed bugs, fewer larvae and less damage than the untreated. Treatments pirate bugs, and lady beetles. Novaluron showed good selec- that maintained a seasonal average at or below the Alabama tivity against big-eyed bugs with no rate response. However, economic threshold of five larvae per 100 plants were Steward the toxicity of Novaluron towards pirate bugs was very rate plus Asana, Tracer, Steward (0.09 and 0.11 pound active ingre- responsive. Novaluron was very easy on the lady beetle popu- dient per acre), Baythroid, S-1812 plus Asana, Denim plus Ka- lation. Steward at 0.11 pound active ingredient showed limited rate Z, and Novaluron (0.068 pound active ingredient per acre). selectivity towards big-eyed bugs, pirate bugs, and lady beetles The top two treatments in reducing fruit damage were Steward in this trial, generally being in the bottom one-half of all treat- plus Asana and Tracer. Most treatments held the seasonal av- ments. Denim was initially quite hard on big-eyed bugs and erage of fruit damage to less than 10% while the untreated was pirate bugs but not lady beetles. However, it did exhibit short 26%. For the second consecutive season, the damage in the residual since populations of all three beneficial species were Denim treatment at 0.01 pound active ingredient per acre was rebounding by the seven DAT evaluation date. not in proportion to the number of escape larvae recorded. Heliothine populations, primarily bollworms, were the This may indicate that the larvae were not feeding as actively heaviest since 1995 at the Prattville test site where 21 treat- behind Denim as with other treatments. Steward at 0.09 pound ments containing the newer lepidopteran compounds were active ingredient per acre performed as well as the 0.11 rate. compared to existing chemistry. A total of five applications were Baythroid at 0.04 outperformed the other pyrethroids (Decis, made between July 16 and August 16. All treatments had sig- Karate Z, XDE-225, and Asana) at the rates used in this test. TABLE 2. NUMBER OF GREEN STINK BUGS PER 100 Row FEET July 12 'July 15- -- July 18 - Average Treatment (lb ai/ac) Nymphs Adults Total Nymphs Adults Total Nymphs Adults Total Nymphs Adults Total Trimax + Bidrin 0.0 (0.03 + 0.33) Centric (0.063) 0.0 Vydate + Asana 0.0 (0.25 + 0.36) Orthene (0.5) 0.0 Bidrin (0.4) 16.7 Centric (0.047) 0.0 Untreated 8.3 Trimax + Bidrin 0.0 (0.03 + 0.25) Intruder + MSO (0.05) 0.0 Karate Z (0.034) 0.0 Vydate (0.33) 8.3 Assail (0.075) 16.7 F 0570 (0.018) 8.3 Intruder + Decis 16.7 (0.036 + 0.023) Centric + Karate Z 8.3 (0.023 + 0.02) Denim (0.01) 8.3 Leverage (0.077) 16.7 Trimax (0.03) 8.3 Trimax (0.047) 16.7 Intruder (0.05) 33.3 Steward + Vydate 0.0 (0.09 + 0.25) Novaluron (0.094) 8.3 Novaluron (0.045) 33.3 Untreated 8.3 Intruder + COC (0.05) 25.0 Untreated 0.0 Novaluron (0.068) 25.0 Steward (0.11) 91.7 0.0 0.0 0.0 0.0 0.0 8.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 16.7 0.0 0.0 0.0 0.0 0.0 8.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 8.3 0.0 0.0 16.7 0.0 0.0 8.3 0.0 0.0 16.7 0.0 0.0 8.3 16.7 0.0 8.3 0.0 8.3 25.0 8.3 0.0 8.3 16.7 0.0 16.7 8.3 0.0 33.3 0.0 8.3 8.3 16.7 8.3 16.7 25.0 33.3 66.7 0.0 8.3 16.7 25.0 16.7 41.7 33.3 8.3 8.3 8.3 25.0 50.0 25.0 0.0 91.7 8.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 8.3 0.0 0.0 0.0 2.8 0.0 2.8 8.3 8.3 0.0 0.0 0.0 0.0 2.8 2.8 0.0 0.0 8.3 5.0 13.3 2.8 1.7 4.4 0.0 0.0 0.0 0.0 0.0 5.6 0.0 5.6 8.3 8.3 5.0 5.0 10.0 1.7 4.4 6.1 0.0 0.0 5.0 5.0 10.0 4.4 1.7 6.1 0.0 0.0 13.3 5.0 18.3 4.4 1.7 6.1 0.0 0.0 16.7 5.0 21.7 5.6 1.7 7.2 0.0 0.0 13.3 8.3 21.7 4.4 2.8 7.2 8.3 8.3 5.0 0.0 5.0 4.4 2.8 7.2 0.0 0.0 8.3 0.0 8.3 8.3 0.0 8.3 0.0 0.0 21.7 0.0 21.7 10.0 0.0 10.0 0.0 0.0 13.3 0.0 13.3 10.0 0.0 10.0 0.0 16.7 8.3 0.0 8.3 11.1 0.0 11.1 0.0 0.0 16.7 13.3 30.0 8.3 4.4 12.8 0.0 8.3 5.0 0.0 5.0 10.0 2.8 12.8 0.0 16.7 8.3 5.0 13.3 11.1 1.7 12.8 0.0 8.3 16.7 5.0 21.7 13.9 1.7 15.6 0.0 0.0 13.3 5.0 18.3 15.6 1.7 17.2 8.3 25.0 13.3 5.0 18.3 10.0 7.2 17.2 8.3 33.3 25.0 0.0 25.0 19.4 5.6 25.0 0.0 0.0 13.3 0.0 13.3 15.6 11.1 26.7 0.0 25.0 41.7 5.0 46.7 25.0 4.4 29.4 8.3 41.7 8.3 0.0 8.3 22.2 8.3 30.6 0.0 8.3 75.0 5.0 80.0 27.8 4.4 32.2 0.0 25.0 30.0 5.0 35.0 26.7 10.0 36.7 0.0 8.3 16.7 16.7 33.3 38.9 5.6 44.4 \---- ----/ 2002COTTONRESEARCHREPORT 29 ALABAMA AGRICULTURAL EXPERIMENT STATION Denim at 0.01 pound active ingredient per acre left the greatest number of escape larvae, other than the untreated plots. S-1812 performed better than Denim and Intrepid but not as well as Steward or Tracer. Intrepid and Larvin were two of the least effective treatments in both escape larvae and fruit damage. The three highest yielding treatments were Denim plus Karate Z, S-1812 plus Asana, and Baythroid. All treatments out yielded the untreated plots by 405 to 669 pounds of seed cotton per acre. Bollgard II was compared to Bollgard and conventional varieties at two sites in Alabama in 2002. Moderate to heavy bollworm/tobacco budworm pressure occurred at both loca- tions. A subeconomic level of both fall armyworms and soy- bean loopers occurred at one test site. All plots were treated as needed with insecticides. The conventional varieties required three applications, at a cost of $28.00 per acre at one site, while the other site received four applications at a cost of $40.00 per acre. Application costs were not included at either site. The Bollgard II with no oversprays yielded the same as, or higher, than the conventional or Bollgard. Measurable fruit damage was present in the conventional plots (due to poor timing of sprays in inclement weather) and the untreated Bollgard plots. No damage from any caterpillar species was detected in the Bollgard II plots. 30 2002 COTTON RESEARCH REPORT NEMATICIDE S IN-SEASON CONTROL OF RENIFORM NEMATODES IN NORTHERN ALABAMA Charles Burmester, Curtis Grissom, and K. S. McLean Severe cotton stunting due to high levels of reniform nema- todes has been observed in northern Alabama fields the last two seasons. In each season the stunting has become appar- ent in early June in random areas across the fields. Information on control measures to reduce reniform nematode damage at this time of the season is limited. In 2002, three fields with very high reniform levels and stunted cotton were located in early June. The fields are iden- tified as Bridgeforth, Anderson, and Murphy. All fields were located in Limestone County and the soil type was a Decatur silt loam at each test site. Side dress treatments of Temik 15G were applied in a two-replication test on the Bridgeforth farm and a three-replication test on the Anderson farm. Temik was sidedressed at 7 pounds per acre at both sites. The.four-repli- cations test on the Murphy farm received no side dress Temik applications. Foliar applications of Vydate were applied at 8.5 and 17.0 ounces per acre in the Anderson and Murphy tests while 8.5, 17.0, and 25.5 ounces per acre were applied in the Bridgeforth field. Soil samples were taken approximately 3 weeks after application to determine nematode control. Yields were determined by hand picking at the Bridgeforth and Murphy sites, but yields were not determined in the Anderson field. In the Bridgeforth field, both Temik and Vydate treatments greatly reduced reniform nematode numbers 4 weeks after ap- plication (see table). Increasing Vydate rates steadily reduced the reniform levels from over 2500 to only slightly over 400 per 150cc of soil. Cotton growth was visually improved by the Temik and Vydate applications. A late season drought greatly reduced yields in this field. The cotton plants delayed by the reniform nematodes were especially affected by the drought. The Temik and Vydate treatments still increased seed cotton yields by between 150 and 250 pounds per acre compared to no treatment. In the Anderson and Murphy fields, Temik and Vydate treatments did not reduce reniform nematode numbers (see table). In fact, reniform numbers were sometimes higher in the Vydate-treated plots than in the non-treated areas. No visual growth differences between nematicide treatments and the check areas were noted in either test. In the Murphy test, seed cotton yields were actually slightly lower in the nematicide treated plots compared to the CONTROL OF RENIFORM NEMATODES IN NORTHERN ALABAMA -Bridgeforth farm- -Murphy farm- Anderson farm' Treatments Reniform 2 Seedcotton Reniform 2 Seedcotton Reniform 2 no/150cc lbs/ac no/150cc lbs/ac no/150cc Check 2588 1263 1198 2033 1674 Temik 7.0 Ibs/ac 1120 1410 - - 1931 Vydate 8.5 oz/ac 1159 1518 1004 1760 4377 Vydate 17.0 oz/ac 708 1472 1370 1800 3295 Vydate 25.5 oz/ac 425 1518 - - - 1 Seed cotton yields were not measured in the Anderson field. 2 Reniform nematodes were sampled approximately three weeks after application. check areas. Although the Bridgeforth field produced very encour- aging results relating to in- season control of reniform nematodes, the lack of re- sponse to the same treat- ments in the Anderson and Murphy fields is quite con- fusing. Tests to evaluate pos- sible soil differences between the sites are being con- ducted. 31 ALABAMA AGRICULTURAL EXPERIMENT STATION EVALUATION OF MESSENGER WITH TEMIK 15G FOR CONTROL OF ROTYLENCHULUS RENIFORMIS ON COTTON IN CENTRAL ALABAMA K. S. McLean, G. W. Lawrence, A. J. Palmateer, J. Hutchinson, J. Jones, and D. Moore This cotton nematicide test evaluated Messenger with Temik 15G for control of the reniform nematode (Rotylenchulus reniformis) on cotton. The test was planted on May 9 at the Prattville Agricultural Research Unit, Prattville, Alabama. The field has a history of reniform nematode infestation and the soil type was a sandy loam. Messenger was applied as a broadcast spray with a backpack CO 2 charged six foot wide boom with flat fan tip 8002E nozzles calibrated to deliver 10 gallons per acre at 20 pounds per square inch. Messenger was applied at the two leaf stage (2LF), pinhead square stage (PHS), full bloom (FB), and/or three weeks after full bloom (FB+3). The nematicide Temik 15G was applied at 3.5 pounds per acre in-furrow at planting. 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 five replications. Blocks were separated by a 20- foot alley. All plots were maintained throughout the season with standard production practices as recommended by the Ala- bama Cooperative Extension System. Reniform nematode popu- lations were monitored monthly throughout the season. Plots were harvested on November 14. Data were statistically ana- lyzed by ANOVA and means compared using Fisher's protected least significant difference test (P < 0.05). Reniform nematode disease pressure was moderate in 2002 due to the dry weather. Significant differences in reniform nema- tode populations were observed in the June, August, and Oc- tober sampling dates. Forty days after planting, no significant differences were observed between the Messenger plus Temik 15 G combination treatments and the control Temik 15 G treat- ment. At eighty-three days after planting, Messenger plus Temik 15G FB+3 treatment had fewer reniform than the Messenger plus Temik 15G 2-L, FB and Messenger plus Temik 15G FB, FB+3 treatments. By 160 days after planting, no differences in reniform populations were observed among the treatments. The average reniform population across the season varied from a low in the Messenger plus Temik 15 G FB+ 3 treatment to a high in the Temik 15 G alone treatment. Seed cotton yields varied over 395 pounds per acre for the Messenger plus Temik 15 G FB+ 3 treatment and Messenger plus Temik 15 G PHS, FB+3 treatment. Averaging all the Messenger treatment yields together produced an increase of 59 pounds of seed cotton per acre greater than the Temik 15 G alone treatment. EFFECT OF MESSENGER COMBINED WITH TEMIK 15G AT VARIOUS APPLICATION TIMINGS ON RENIFORM NEMATODE POPULATIONS AND SEED COTTON YIELD Treatment-product-rate/ac Applications Reniform/150 cc 3 of soil' Seed cotton of Messenger 40 DAP 83 DAP 160 DAP Average lb/ac Temik 15G 3.5 lb/ac no application 2101 8189 ab 5840 4429 a 2166 ab Messenger 2.25 oz/ac + Temik 15G 3.5 lb/ac PHS, FB, FB+3 1684 5562 ab 4666 3374 ab 2158 ab Messenger 2.25 oz/ac + Temik 15G 3.5 Ib/ac 2-L, FB 1684 9517 a 6335 4780 ab 2287 ab Messenger 2.25 oz/ac + Temik 15G 3.5 lb/ac PHS, FB+3 2472 7292 ab 5670 4255 ab 2097 b Messenger 2.25 oz/ac + Temik 15G 3.5 lb/ac FB, FB+3 1452 9085 a 4063 4046 ab 2302 ab Messenger 2.25 oz/ac + Temik 15G 3.5 Ib/ac 2-L 1931 7107 ab 5933 4139 ab 2204 ab Messenger 2.25 oz/ac + Temik 15G 3.5 lb/ac PHS 2348 6010 ab 5516 3865 ab 2173 ab Messenger 2.25 oz/ac + Temik 15G 3.5 lb/ac PH +2 1184 6412 ab 6767 3987 ab 2097 b Messenger 2.25 oz/ac + Temik 15G 3.5 Ib/ac FB 2018 5655 ab 4573 3458 ab 2219 ab Messenger 2.25 oz/ac + Temik 15G 3.5 lb/ac FB+3 983 4882 b 3646 2774 b 2492 a FP LSD (P < 0.05) 1487 4332 4001 1734 356 'At planting, population of R. reniformis was 1586/150 cm 3 of soil. 32 2002 CorroN RESEARCH REPORT 33 IMPACT OF FUMIGATION WITH TELONE AND APPLICATIONS OF TEMIK ON COTTON IN RENIFORM NEMATODE William S. Gazaway and Don Moore Reniform nematodes continue to be a major impediment to successful cotton production in Alabama. Losses in cotton fields heavily infested with reniform nematodes (Rotylenchulus reniformis) can range from 20% to as high as 60% depending on growing conditions. Historically, Telone II and Temik 15 G have been used to moderate these losses and allow growers to successfully produce a profit in these fields. Currently cotton producers inject Telone II in the spring approximately 18 inches deep into well-pulverized, raised soil beds 7 days before plant- ing. Temik 15G, applied at 5 to 7 pounds per acre in the seed furrow, is the most frequently used nematicide to control reni- form nematodes. Past trials have shown that both nematicides can be effective against reniform nematodes when applied when conditions are favorable. Trials in north Alabama had shown a substantial yield increase with a side dress application of Temik 15G (7 pounds per acre) applied at pinhead square. This test was set up to determine if similar results could be obtained with side dress applications of Temik applied at pinhead square used in combination with either Telone II applied pre-plant or Temik 15G applied in the furrow at planting. The Avant cotton field near Prattville, Alabama, was se- lected because it has historically lost substantial cotton yields as a result of a heavy infestation of reniform nematodes. The field, a sandy loam (66% sand, 29% silt, and 5% clay), was disced thoroughly and bedded up on April 3 2002. Treatments were arranged in a randomized complete block design with six replicates. Plots were four 36 inch rows, 25 feet long. Data were INFESTED FIELDS NEAR PRATTVILLE taken from the center two rows. Ammonium nitrate (90 units per acre) was applied broadcast on April 8. Telone II was injected 18 inches beneath the top of the raised bed surface at 3 gallons per acre or 5 gallons per acre to designated plots on April 18. All plots not receiving Telone were sub-soiled at the same 18 inch depth. On May 8, all plots were planted with Sure-Grow 501 BR seed treated with the insecticide Cruiser. Temik 15 G was applied in the seed furrow at 5 pounds per acre to desig- nated plots on the same date. Roundup (at a rate of 1 pound of active ingredient per acre) was applied for weed control on June 5. Temik 15G was later applied as a side dress treatment on June 13 to designated plots. Cotton plots were defoliated on September 12 with 6 ounces per acre Ginstar plus Prep (1.5 pints per acre). Reniform populations were found to average more than 200 per 100cc in the spring prior to planting. A 6-week nema- tode sampling after crop emergence was not taken because the field was too dry. Excessive rainfall during September and Oc- tober delayed cotton harvest until November 14. During that period, cotton had to be defoliated a second time due to re- grow. Though no statistical difference could be discerned among treatment yields (Table 1), all nematicide-treated plots appeared to yield better than the untreated plots with the exception of the plots in the fifth replication (the fifth tier) (see Table 2). For some unknown reason, cotton yield was unusually high in the untreated control plots in the fifth tier. Table 2, in which tier 5 is excluded, is included for your information. TABLE 1. YIELD RESPONSE TO TELONE AND TEMIK APPLICATIONS Treatment Rate/acre Time of application Seed cotton Ib/ac 1 Telone II 3 gal fumigation 1810 a 2 Telone II + Temik 15G 3 gal + 5 lb fumigation + pinhead square 1718 a 3 Telone II 5 gal fumigation 1781 a 4 Temik 15G 5 lb at planting 1665 a 5 Temik 15G + Temik 15G 5 lb + 5 lb at planting + pinhead square 1709 a 6 Cruiser treated seed 1476 a LSD (P= .05) 285.6 TABLE 2. COTTON YIELD EXCLUDING FIFTH REPLICATION Treatment Rate/acre Time of application Seed cotton Ib/ac 1 Telone II 3 gal fumigation 1749 2 Telone II + Temik 15G 3 gal + 5 Ib fumigation + pinhead square 1646 3 Telone II 5 gal fumigation 1706 4 Temik 15G 5 lb at planting 1688 5 Temik 15G + Temik 15G 5 Ib + 5 Ib at planting + pinhead square 1664 6 Cruiser treated seed 1319 ALABAMA AGRICULTURAL EXPERIMENT STATION IMPACT OF SIDE DRESS TEMIK APPLICATIONS ON COTTON PRODUCTION IN RENIFORM NEMATODE INFESTED W. S. Gazaway and J. R. Akridge Reniform nematode is a major limiting factor to successful cotton production in Alabama. Losses in cotton fields heavily infested with reniform nematodes (Rotylenchulus reniformis) can range from 20% to as high as 60% depending on growing conditions. Telone II and Temik 15 G have been used success- fully to moderate these losses and allow growers to produce a profit in these fields. Temik 15G, applied at 5 to 7 pounds per acre in the seed furrow at planting, is preferred by most Ala- bama cotton producers and can be quite effective against reni- form nematodes. Moreover, earlier trials in north Alabama had shown a substantial increase in yield with an application of Temik 15G (7 pounds per acre) or Vydate (2 pints per acre) at pinhead square. Trials were conducted to determine if side dress applications of Temik would produce similar results in central and south Alabama. The test was placed in the Ward Brothers cotton field near Huxford, Alabama. This is fourth year that the side dress Temik test has been in this field. The field, a loam (49% sand, 34% silt, and 17% clay), was disced thoroughly and bedded up on April 9 2002. Treatments were arranged in a complete ran- domized block design with six replicates (Table 1). Plots were FIELDS NEAR HuxFORD four 36 inch rows, 25 feet long. Nematode soil samples and yield data were taken from the center two rows. Telone II was injected 18 inches beneath the top of the raised bed surface at the rate of 3 gallons per acre to designated plots on April 9. Raised beds in all plots not receiving Telone were sub-soiled at the same 18-inch depth. On May 2, all plots were planted with DP 458 B/RR seed, and treated with the insecticide Cruiser. Temik 15 G was applied in the seed furrow at 5 pounds per acre or 7 pounds per acre to designated plots. Temik 15G was later applied as a side dress treatment on June 28 to designated plots. All other cultural practices, weed control, and insect con- trol were according to Auburn University recommendations. Nematode samples were taken on April 9 and June 12. Due to excessive rainfall (more than 30 inches) from Sep- tember through November, cotton could not be picked. Cotton either fell to the ground or rotted in the bolls. Cotton losses in the area exceeded 80%. Although no yield data are available, some visual observations of cotton growth and boll produc- tion were made in the late summer before the onset of the rains. Cotton in plots treated with Telone alone and the two Temik dress treatments with either Telone or Temik at planting had the most vigorous growth and the best boll set (Table 2). TABLE 1. SUMMARY OF TREATMENTS FOR THE 2002 TEMIK SIDE DRESS TEST Treatment Rate/acre Application method 1 Cruiser Seed treatment for insect control 2 Temik 15G 3.5 lb In seed furrow at planting 3 Temik 15G 5.0 lb In seed furrow at planting 4 Temik 15G 7.0 lb In seed furrow at planting 5 Temik 15 G + Temik 15G 5.0 Ib + 7.0 Ib In seed furrow at planting. Followed by side dress application at pinhead square. 6 Telone II 3 gal Injected 18 inches deep in raised beds prior to planting. 7 Telone II + Temik 15G 3 gal + 7.0 lb Injected 18 inches deep in raised beds prior to planting. Side dress application at pinhead square. TABLE 2. RENIFORM POPULATION RESPONSE TO TEMIK SIDE DRESS APPLICATIONS Treatment Rate/acre Application Reniform/100cc soil April 9 June 12 1 Cruiser Seed treatment 152 a 1108 a 2 Temik 15G 3.5 Ib At plant 50 b 737 ab 3 Temik 15G 5.0 Ib At plant 55 b 794 ab 4 Temik 15G 7.0 At plant 59 b 553 ab 5 Temik 15G + Temik 15G 5.0 Ib + 7.0 Ib At plant 64 b 931 ab Side dress 6 Telone II 3.0 gal Pre-plant 83 b 271 b 7 Telone II + Temik 15G 3.0 gal + 7.0 lb Pre-plant 104 b 492 ab Side dress LSD (P= .05) 43.8 492.3 34 2002 COTTON RESEARCH REPORT FALL FUMIGATION VERSUS SPRING FUMIGATION FOR RENIFORM CONTROL IN HEAVILY INFESTED COTTON FIELDS W. S. Gazaway and 3. R. Akridge Telone II has been shown to be an effective nematicide when applied under proper soil conditions. Telone II, unlike other fumigants, is most effective when applied to drier soil at warmer temperatures. In Alabama, such conditions often occur in the fall after cotton has been picked. Conversely, Telone does not perform well when applied to overly wet and cooler soils-conditions that are often present in the spring. Coupled with the fact that Telone requires a 7- to 10- day waiting period prior to planting, a fall application would be more practical than a spring application. The purpose of this experiment was to compare a Telone fall application to a Telone spring application and to the conventional Temik in-furrow application in the spring. Treatments were arranged in a randomized complete block design and replicated five times. Plots contained four rows and FALL AND SPRING FUMIGATION IMPACT ON RENIFORM POPULATIONS Nematicide Rate/acre Application Reniform/100cc soil April 9 June 12 Telone II 3 gal Fall 27 a 478 b Telone II 5 gal Fall 30 a 395 b Telone II 3 gal Spring 34 a 218 b Temik 15G 7 Ib At-planting 28 a 871 a Di-Syston 15G 7 Ib At-planting 33 a 392 b LSD (0.05) 19.2 313.6 were 25 feet long. The entire test area of the field was disked and subsoiled on December 4 2001. At that time two rates of Telone II (3 and 5 gallons per acre) were injected 18 in deep in raised seed beds to assigned plots. The following spring, Telone application was made on April 9, 2002. Temik was applied in- furrow when cotton (DP 655 B/RR) was planted on May 2. Nematode samples were pulled on December 4, April 9, June 29, and November 31. The plots were not picked due to excessive boll rot caused by more than 30 inches of rain from September through November 2002. Due to the excessive rainfall, it was impossible to pick cotton from any of the tests in Huxford. More than 30 inches of rain fell from September through November, 2002. Most of the cotton, which was open during this exceedingly wet period, fell to the ground and rotted in the field. Only soil samples for nematode analyses are available for this test. Visual ratings on general cotton growth and boll production were made in the late summer prior to the rains, however. All treatments receiv- ing Telone II appeared to have more vigorous growth and more boll production than the Temik at-planting treatment or the no nematicide treatment (see table). Cotton receiving fall applica- tion of 5 gallons per acre had the most vigorous growth fol- lowed by Telone treatments at 3 gallons per acre applied in the spring and in the fall, respectively. Based on the performance of Telone II fall applications in this test and previous tests conducted the past three years, Telone II applied the fall ap- pears to be the superior application method. EFFECT OF SUMMER CROPS AND WINTER COVER CROPS ROTATION ON RENIFORM NEMATODE POPULATODE OPULATIONS IN COTTON W. S. Gazaway and 3. R. Akridge A rotation study was begun in 1997 to determine the im- pact of winter cover crops and summer non-host crops rotated alternate years with cotton on cotton production in fields heavily infested with reniform nematodes. The tests were initiated with winter cover crops or a fallow in the fall of 1997 followed by summer non-host crops planted to designated plots in the spring of 1998. Since that time winter cover crops or a fallow have continued to be planted each fall to the same designated plots, while in the summer cotton has been rotated with non- host crops in alternate years. For example, cotton was planted to all test plots in the spring of 1999. Non-host crops were planted in spring of 2000. Cotton was planted to all plots again in the spring of 2001 and nonhost crops were planted in the spring of 2002. However, two treatments, designated as con- tinuous cotton, have been planted every season in cotton. One of the treatments received a nematicide; the other treat- ment received only an insecticide. The nonhost summer crops used in this study were corn, rye, a reniform resistant soybean variety, and peanut. The field (49% sand, 34% silt, and 17% clay) has had a high infestation of reniform nematodes for more than 12 years and, as a result, has experienced substantial cotton yield losses 35 ALABAMA AGRICULTURAL EXPERIMENT STATION over that period. The experimental design was a split plot, ran- domized design with five replications. Plots consisted of eight rows 36 inches wide and 25 feet long. Main plots were the winter cover crops that include vetch (Cahaba White), rye (Wren's Abruzzi), and fallow. Subplots are summer crops that include cotton (DP 655 B/RR), corn (GarstAP-8251), soybean (AgriPro 5588-RR), and peanut (Southern Runner). In 2002, plots were planted with non-host summer crops. Cotton was planted in the continuous cotton plots. One of the continuous cotton treatments was treated with Temik 15G at a rate of 7 pounds per acre in the seed furrow at planting. The tillage system was a strip till system. Soil samples were pulled for nematode analy- ses from the two inner rows of each plot in the spring prior to planting and in the fall after crops had been harvested. All other cultural practices, weed control, and insect control were implemented according to Auburn University recommendations. The 2002 season experienced extremely unfavorable grow- ing conditions as a result of bad weather. The spring was so dry that cotton had to be replanted in the continuous cotton plots a second time on May 24. Dry weather persisted through- out most of the late spring and early summer. However, from late August through much of November, rain fell continuously, rotting most of the cotton and preventing its harvest. More than 40 inches of rain fell during this period. Consequently, it was impossible to obtain cotton yield data. Soil samples for nematode analyses were taken in late April and again in late October. Reniform nematode fall populations were lower than in most years, because the field was extremely wet when the soil samples were taken (Table 1). Soil samples are generally taken in the field from 6 to 10 inches deep. Under these ex- tremely wet conditions, reniform nematodes may have moved deeper into the soil, beneath the sampling zone. The popula- tion response to summer crops appears to be relative because peanut and corn reduced reniform populations in 2002 in a similar manner as they had done in previous years (Table 1). The nematicide Temik 15G also reduced reniform populations but to a lesser degree than either peanut or corn (Table 1). Winter cover crops as in previous years had no effect on reni- form populations (Table 2). Surprisingly, vetch, which increases reniform nematode populations in greenhouse tests, did not increase reniform populations in the field during the winter months. TABLE 1. IMPACT OF SUMMER CROPS ON RENIFORM NEMATODE POPULATIONS Summer crop Reniform nematodes/100 cc soil April 15 Oct. 29 Cotton 4020 1130 Cotton + Temik 3115 649 Corn 2458 325 Soybean 2774 738 Peanut 2843 375 LSD (P=.05) 840 240 TABLE 2. IMPACT OF WINTER COVER ON RENIFORM NEMATODE POPULATIONS Winter cover Reniform nematodes/100 cc soil April 15 Oct. 29 Fallow 3391 591 Vetch 2644 619 Rye 3092 719 LSD (P=.05) 650 186 36 2002 CorroN RESEARCH REPORT FUNGICIDES EVALUATION OF TERRA CONTROL SC 823 ON IRRIGATED AND NONIRRIGATED COTTON Edward Sikora, Larry Wells, Don Moore, Bobby E. Norris, and Maria Rivas The soil conditioner Terra Control SC 823 is an ecologi- cally compatible polymer dispersion for stabilizing topsoil lay- ers. Terra Control forms a three-dimensional matrix in the sub- soil that is permeable to water and oxygen but is stable against soil erosion due to wind or rain. Terra Control retains moisture longer in the soil and protects soil and plants from drying out, allowing for economical water management. The objective of these studies was to determine if a single application of Terra Control SC 823 after planting would pro- vide long-term water retention in the root zone that would ben- efit plants during extended periods of drought under nonirrigated and/or irrigated conditions. Irrigated and nonirrigated trials were conducted at the Wiregrass Research and Extension Center and the Tennessee Valley Research and Extension Center. A nonirrigated trial was also established at the Prattville Agricultural Research Unit. Irrigated trials were conducted using overhead center-pivot irrigation. Each trial consisted of three treatments, replicated six times, in a randomized complete block design. Each treat- ment/replication consisted of a four-row plot, 30.0 feet long. Sure-Grow 125 BR was planted on June 4 at the Wiregrass Center, Sure-Grow 501 BR was planted on May 13 at the Prattville Agricultural Research Unit, and Sure-Grow 747 was planted on April 16 at the Tennessee Valley Center. Terra Control SC 823 treatments were applied as a broadcast spray at planting at 7.5 or 10 gallons per acre. Fertilizer applications were determined by soil test information. Insect and weed control required ap- plying insecticide and herbicides as needed. Seed cotton yield was determined at harvest. There were no significant differences in yield among treat- ments except at the Tennessee Valley Center-irrigated trial (see table). In that test, the 10-gallon rate of Terra Control increased cotton yield significantly more than the untreated con- EFFECT OF TERRA CONTROL SC 823 ON COTTON YIELD ON IRRIGATED AND NONIRRIGATED COTTON AT THREE LOCATIONS IN ALABAMA Nonirrigated Irrigated- Variety Prattville Tn. valley Wiregrass Tn. valley Wiregrass Ib/ac cotton seed yield Control 2047 a 1169 a 1228 a 2108 b 1064 a Terra control 7.5 gal/ac 1955 a 1217 a 930 a 2191 ab 962 a Terra control 10 gal/ac 2024 a 1200 a 1145 a 2274 a 913 a 1 Numbers followed by the same letter are not significantly different. trol. This was the second year of this study. A total of 12 field tests have been con- ducted in 2001 and 2002 evaluating Terra Control SC 823 on cotton in both irri- gated and nonirrigated fields. In 11 of the 12 studies, no sig- nificant differences in cotton yield among treatments have been observed. 37 ALABAMA AGRICULTURAL EXPERIMENT STATION EVALUATION OF PLANTING DATE FOR RESPONSE TO BOLL ROT DISEASE IN ALABAMA A. J. Palmateer, K. S. McLean, G. W. Lawrence, J. L. Hutchinson, J. R. Jones, K. Glass, and M. D. Pegues A planting date trial was conducted to evaluate cotton boll rot incidence in relation to the date of planting. The test was planted at the Gulf Coast Research and Extension Center, Fairhope, Alabama. The soil type was a Malbis fine sandy loam. Plots consisted of two rows, 25 feet long, with a between-row spacing of 40 inches. Plots were arranged in a randomized com- plete-block design with four replications. A 20-foot alley sepa- rated blocks. Two varieties-Sure-Grow 215 BG/RR (early sea- son) and Deltapine DP 555 BG/RR (late season)-were planted on April 18 and every two weeks thereafter until June 1. Cotton boll rot was evaluated by recording the number of healthy bolls and diseased bolls from a 0.001 acre section within each plot. Disease index ([# diseased bolls / total # counted] x 100) was calculated for each variety on August 8, August 15, August 29, September 13, October 1, and October 18. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production prac- tices as recommended by the Alabama Cooperative Extension System. Data were statistically analyzed using PROC GLM, and means were compared with Fisher's protected least signifi- cant difference test (P < 0.05). Cotton boll rot disease incidence was high in 2002 and yield data are not included due to tropical storms and hurricane conditions late in the season. The initial disease index taken on August 8 for Sure-Grow 215 BG/RR and Deltapine DP 555 BG/ RR was lowest for the May 2 planting (see table). The May 16 and June 1 plantings were beginning to flower; therefore, the disease index is listed as zero. No significant differences were observed for disease index recorded on August 15. The mean disease index for Sure-Grow 215 BG/RR planted on May 2 was significantly less for both varieties on the June 1 planting and for Deltapine DP 555 BG/RR planted on May 2 and May 16. DISEASE INDEX BY PLANTING DATE Planting Disease index' Variety date Aug. 1 Aug. 15 Aug. 29 Sept. 13 Oct. 1 Oct. 18 Mean Sure-Grow 215 BG/RR April 18 4.0 ab 2 2.2 a 6.4 ab 6.1 a harvested harvested 3.1 de Deltapine DP 555 BG/RR April 18 5.8 a 5.0 a 6.6 ab 3.8 ab harvested harvested 3.5 cde Sure-Grow 215 BG/RR May 2 2.0 bc 1.6 a 5.6 abc 6.0 a harvested harvested 2.5 e Deltapine DP 555 BG/RR May 2 4.9 ab 4.1 a 9.5 a 2.7 b 7.0 b 10.9 a 6.5 ab Sure-Grow 215 BG/RR May 16 0.0 c 2.7a 3.3 bc 4.3 ab 7.8 b 8.6 a 4.4 b-e Deltapine DP 555 BG/RR May 16 0.0 c 1.4 a 3.1 bc 4.3 ab 8.2 b 11.9 a 4.9 a-d Sure-Grow 215 BG/RR June 1 0.0 c 0.8 a 2.6 bc 4.7 ab 15.1 a 16.9 a 6.7 a Deltapine DP 555 BG/RR June 1 0.0 c 5.5 a 1.7 c 4.9 ab 6.9 b 13.9 a 5.5 abc LSD (P <0.05) 3.3 5.3 4.5 2.8 6.5 9.2 2.2 SDisease index = (number of diseased boils / number of total bolls) x 100. 2 Means within columns followed by different letters are significantly different according to Fisher's LSD (P < 0.05). 38 2002 CrroTTON RESEARCH REPORT EVALUATION OF SELECTED FUNGICIDES FOR CONTROL OF COTTON BOLL ROT DISEASE ON DELTAPINE NUCOTN 33B A. J. Palmateer, K. S. McLean, G. W. Lawrence, J. L Hutchinson, 3. R. Jones, K. Glass, and M. D. Pegues A cotton fungicide test was planted on May 9 on the Gulf Coast Research and Extension Center at Fairhope, Alabama. The test site was a Malbis fine sandy loam soil. All fungicides were applied as a foliar spray using TX- 12 cone nozzles mounted on ground slides spraying upward with two nozzles per row calibrated to deliver 26 gallons per acre at 75 pounds per square inch. Plots consisted of two rows, 40 feet long with a 38 inch wide row spacing arranged in a randomized complete block design with five replications. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production prac- tices as recommended by the Alabama Cooperative Extension System. Disease index ([number of diseased bolls / total num- ber counted] x 100) was calculated for each variety. Boll rot ratings were conducted on October 18 and plots were harvested on November 25. Data were statistically analyzed using PROC GLM, and means were compared with Fisher's protected least significant difference test (P < 0.05). The incidence of boll rot was high due to tropical storms and hurricane conditions. No fungicide significantly reduced the number of diseased cotton bolls as compared to the control (see table). Seed cotton yields varied by 224 pounds per acre for the Quadris 2SC first plus full bloom application and Rovral 4F first bloom applications. No treatments produced a signifi- cantly greater yield than the control. However, the average of the first bloom, first bloom plus full bloom, and full bloom appli- cations increased cotton yield an average of 69, 95, and 32 pounds per acre, respectively. Quadris 2SC, Benlate 50WP, and Rovral 4F increased cotton yield an average of 170, 132, and 143 pounds per acre, respectively. EVALUATION OF SELECTED FUNGICIDES FOR CONTROL OF BOLL ROT DISEASE ON DELTAPINE NUCOTN 33B Fungicide, application rate, schedule Healthy bolls' Diseased bolls' Disease index 2 Seed cotton yield no. no. Ib/ac Quadris 2SC, 12 fl oz/ac, First bloom 49.0 ab 10.4 a ab 24.3 ab 1592 ab Quadris 2SC, 12 fl oz/ac, First + full bloom 61.8 a 7.0 b 11.7 b 1708 a Quadris 2SC, 12 fl oz/ac, Full bloom 57.4 ab 15.0 ab 26.8 ab 1545 ab Bentate 50WP, 3.3 dry oz/ac, First bloom 57.2 ab 11.0 ab 21.1 ab 1636 ab Benlate 50WP, 3.3 dry oz/ac, First + full bloom 60.4 ab 11.0 ab 19.9 ab 1587 ab Benlate 50WP, 3.3 dry oz/ac, Full bloom 57.4 ab 13.4 ab 35.2 ab 1507 ab Folicur 3.6F, 7.2 fl oz/ac, First bloom 54.0 ab 13.6 ab 32.3 ab 1544 ab Folicur 3.6F, 7.2 fl oz/ac, First + full bloom 62.0 a 8.0 ab 12.9 b 1347 ab Folicur 3.6F, 7.2 fl oz/ac, Full bloom 44.2 b 10.0 ab 24.0 ab 1306 ab Terraclor 4F, 16 fl oz/ac, First bloom 58.8 ab 9.2 ab 16.1 ab 1551 ab Terraclor 4F, 16 fl oz/ac, First + full bloom 53.2 ab 13.4 ab 31.7 ab 1443 ab Terraclor 4F, 16 fl oz/ac, Full bloom 55.6 ab 9.2 ab 17.2 ab 1371 ab Rovral 4F, 4 fl oz/ac, First bloom 44.4 b 8.2 ab 19.2 ab 1483 b Rovral 4F, 4 fl oz/ac, First + full bloom 44.0 b 16.0 a 48.1 a 1515 ab Rovral 4F, 4 fl oz/ac, Full bloom 51.6 ab 9.4 ab 17.2 ab 1764 ab Messenger, 2.25 dry oz/ac First bloom 57.6 ab 9.2 ab 17.6 ab 1267 ab Messenger, 1.25+2.25 dry oz/ac, First + full bloom 57.0 ab 10.4 ab 18.1 ab 1639 ab Messenger, 2.25 dry oz/ac, Full bloom 45.0 b 10.0 ab 28.8 ab 1369 ab Untreated control 53.2 11.2 ab 42.6 ab 1445 ab LSD(P < 0.05) 16.5 8.7 33.9 392 1 Number of bolls per 50 ft of row. 2 Disease index = (# diseased bolls / # total bolls) x 100. 3 Means within columns followed by different letters are significantly different according to Fisher's LSD (P < 0.05). 39 ALABAMA AGRICULTURAL EXPERIMENT STATION FOLIAR FUNGICIDES AND FERTILIZERS FOR BLACK BELT COTTON Dennis Delaney, Kathy McLean, C. Dale Monks, Charles Mitchell, Ed Sikora, Rudy Yates, Kevan Tucker, and Bob Goodman Cotton producers in the Black Belt area have experienced a severe production problem that has become more common in recent years. The syndrome has been described as "early leaf drop" and often involves fields that show very good yield potential with a heavy boll load set early in the season. Cotton leaves in the affected fields develop leaf spots, mainly attrib- uted to Cercospoa spp. and Alternaria spp. fungi, during late bloom through early boll fill. These leaf spots spread and the affected leaves fall off prematurely, adversely affecting boll fill and yield, and sometimes are associated with early stalk death. Potassium deficiency has been speculated to be a contributing factor; however, field symptoms do not follow typical deficiency symptoms, and the problem often occurs where K fertilizer has been applied and soil test levels are high. An experiment was established on a Kipling clay loam on Roy Etheridge's farm near Hugo in Marengo County, Alabama, to investigate whether foliar applications of fungicides and/or fertilizers might prevent symptoms long enough for normal boll fill to occur. Initial soil pH was 6.8, and soil test levels of all nutrients were rated high or above, with K levels rated very high (683 pounds per acre). The cotton variety planted was FiberMax 989 BR. Leaf samples taken at early bloom revealed that foliar K levels were rated deficient, with only 0.88% K versus recommended sufficiency levels of 1.5 to 3.0%. All other nutrients were rated sufficient. Starting at early bloom, broadcast fungicide applications of Penncozeb 75DF at 1.4 pounds per acre or Quadris at 6 fluid ounces per acre, with and without foliar fertilizer, were made every 7 to 10 days, for a total of six applications. Foliar fertilizer treatments contained 5 pounds per acre each of N and K20, 0.1 pound per acre each of B, Zn, Fe, and Mg, 0.2 pounds per acre of S, and 20 grams per acre of Mo for each application. Growing conditions were generally very good, with little moisture stress. Initial foliar fertilizer sprays caused some leaf bur due to high air temperatures. These symptoms were difficult to visu- ally separate from diseased spots and are reflected in the rat- ings on August 16 (see table). Smaller droplet size and applica- tion earlier in the day helped avoid damage with later sprays. Ratings were made again a week later on fungicide and check plots, but not foliar-fertilized plots due to the still apparent damage. These ratings showed that both Penncozeb and Quadris decreased leaf spotting compared to check plots, but that foliar fertilizer sprays increased it. Leaf drop or senescence ratings revealed that all treat- ments with foliar fertilizer had less leaf drop than the check. Green boll counts made at harvest showed that these plots also matured later, with more unopened bolls than check plots. Fungicides applied alone did not affect leaf drop or maturity. Plots were hand harvested when more than 95% of the cotton was open. The only significant difference noted in seed cotton yields was between Quadris alone and Penncozeb plus foliar fertilizer, but neither was significantly different from the check. When estimated yields from green bolls not harvested were added to each plot's total weight, there were no signifi- cant differences in final yield between treatments (not shown). These data indicate that in a year with relatively good weather, low stress, and low disease levels, applications of foliar fungicides decreased leaf damage from fungi, but did not affect yields. Foliar fertilizer applications also did not increase yields, but damaged some leaf tissue and delayed maturity. Further studies are needed under conditions of higher disease pressure to determine the value of these treatments. Producers should also be cautioned that some of the experimental treat- ments are not yet labeled for cotton. FOLIAR FUNGICIDES AND FERTILIZERS FOR BLACK BELT COTrON, 2002 Leaf spot Leaf spot Leaf drop Seed cotton Green bolls Treatment Rate Aug. 16 Aug 23 Aug. 27 yield Sept. 23 % % % 10lb/ac no/16 row-ft Penncozeb 75DF 1.4 lb/ac 5.0 d' 6.3 b 33.8 a 2396 ab 14.0 c Foliar Fertilizer 24.5 b 18.8 bc 2410 ab 18.5 bc Penncozeb 75DF 1.4 Ib/ac 28.0 a 13.8 c 2314 b 28.0 ab + Foliar fertilizer Quadris 6 oz/ac 3.0 d 5.8 b 30.0 ab 2668 a 11.8 c Quadris 6 oz/ac 23.8 b 17.5 bc 2559 ab 31.5 a + Foliar fertilizer Check 12.5 c 18.3 a 41.3 a 2614 ab 9.8 c LSD (P=.10O) 2.8 5.7 14.6 342 12.7 1 Means followed by same letter do not significantly differ (P=.10, LSD) 40 2002 CorroN RESEARCH REPORT EVALUATION OF SELECTED SEED TREATMENTS FOR MANAGEMENT OF COTTON SEEDLING DISEASE IN NORTH ALABAMA K. S. McLean, A. 3. Palmateer, 3. L. Hutchinson, and B. E. Norris This cotton fungicide test evaluated various seed treat- ments for control of cotton seedling disease. The test was planted on April 15 at the Tennessee Valley Research and Ex- tension Center, Belle Mina, Alabama. The field had a history of cotton seedling disease and the soil type was a Decatur silty loam. Soil temperature was 65 0 F at a 4-inch depth at 10 a. m. with adequate moisture at planting. Fungicides were applied as a seed treatment 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 rep- lications. High disease incidence plots were infested with mil- let seed inoculated with Pythium spp. and Rhizoctonia solani. Blocks were separated by a 20-foot alley. The nematicide Temik 15G (5 pounds per acre) was applied in-furrow at planting. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production prac- tices as recommended by the Alabama Cooperative Extension System. Stand counts and skip index ratings were recorded at 2, 4, and 6 weeks after planting to determine the percent seed- ling loss and stand density due to cotton seedling disease. Plots were harvested on September 24. Data were statistically analyzed by ANOVA and means compared using Fisher's pro- tected least significant difference test (P=0.05). Cotton seedling disease incidence was high in 2002 due to cold wet weather. In the high disease incidence plots, differ- ences (P< 0.05) in seedling stand were observed at 2, 4, and 6 weeks after planting (Table 1). At 2, 4, and 6 weeks after plant- ing, nine seed treatments improved seedling survival compared to the control. A lower skip index (P< 0.05), indicating a more evenly spaced seedling stand, was observed at 6 weeks after planting in the nine seed treatments. No seed treatments in- creased yields over the control (P< 0.05); however, A 13012 FS 125,A13012 FS 125 plus Systhane 40 WSP, andApron XL 3 LS plus Maxim 4 FS plus Systhane 40 WSP increased yields compared to Allegiance-FL plus Baytan 30 plus Thiram 42-S plus Azoxystrobin plus Allegiance-FL plus Baytan 30. The average seed cotton yield from all fungicide-treated plots was 375 pounds per acre greater than the untreated control. Under low disease pressure, stand was not increased by any seed treatment compared to the control at 2, 4, or 6 weeks after plant- ing (Table 2). Correspondingly, a lower skip index was improved compared to the control. However, no treatment increased yields over the control (P< 0.05). Yield was increased in three seed treatments under high disease pressure but not under low dis- ease pressure. TABLE 1. EFFECT OF SELECTED SEED TREATMENTS ON COTTON STAND, SKIP INDEX, AND SEED COTTON YIELD UNDER HIGH DISEASE PRESSURE IN NORTH ALABAMA Treatment Rate a.i./100 kg seed Stand 25 ft row Skip index Seed cotton 14 DAP 28 DAP 42 DAP Ib/ac Control 13.6 5.4 2.0 22.8 2835 A13012 FS 125 25.0 g 35.2 21.2 18.6 13.8 3397 A13012 FS 125 25.0 g 32.8 20.2 19.6 16.8 3313 A13012 FS 125 25.0 g 25.4 17.0 14.8 19.0 3520 A13012 FS 125 + Systhane 40 WSP 25.0 + 21.0 g 37.4 32.4 32.4 8.4 3415 A13012 FS 125 + Systhane 40 WSP 25.0 + 21.0 g 44.8 33.6 34.4 11.4 2984 A13012 FS 125 + Systhane 40 WSP 25.0 + 21.0 g 35.6 30.8 28.6 14.8 3528 Apron XL 3 LS + Maxim 4 FS 7.5 + 2.5 36.4 27.0 26.8 11.8 3781 + Systhane 40 WSP + 21.0g Allegiance-FL + Baytan 30 15.0 + 10.0 12.8 9.0 7.4 17.8 2733 +Thiram 42-S + 31.0g Allegiance-FL + Baytan 30 15.0 + 10.0 42.2 25.0 23.6 15.6 3196 +Thiram 42-S + 31.0 + Delta Coat AD 3.24 FS + 300.0 g Allegiance-FL + Baytan 30 15.0 + 10.0 25.8 18.2 16.6 16.2 2412 + Thiram 42-S + Azoxystrobin + 31.0 + 3.0 + Allegiance-FL + Baytan 30 + 15.0 + 5.0 g Allegiance-FL + Vitavax-PCNB 3.36 LS 15.0 + 176.0 15.0 6.0 7.6 20.4 3146 + Thiram 42-S + 31.0 g Azoxystrobin + Apron XL 3 LS 15.0 + 7.5 28.6 6.4 5.6 21.2 3110 + Maxim 4 FS + 2.5 g LSD P = (0.05) 11.7 6.8 7.3 4.7 1056 41 TABLE 2. EFFECT OF SELECTED SEED TREATMENTS ON COTTON STAND, SKIP INDEX, AND SEED COTTON YIELD UNDER Low DISEASE PRESSURE IN NORTH ALABAMA Treatment Rate a.i./100 kg seed Stand 25 ft row Skip index Seed cotton 14 DAP 28 DAP 42 DAP lb/ac Control - 65.6 64.0 62.4 2.2 3144 A13012 FS 125 25.0 g 57.4 55.0 61.8 2.2 3313 A13012 FS 125 25.0 g 57.2 58.4 56.6 2.8 3321 A13012 FS 125 25.0 g 49.8 62.2 52.4 2.4 3078 A13012 FS 125 + Systhane 40 WSP 25.0 + 21.0 g 50.6 46.8 51.6 5.8 2825 A13012 FS 125 + Systhane 40 WSP 25.0 + 21.0 g 51.4 55.6 51.2 3.6 3120 A13012 FS 125 + Systhane 40 WSP 25.0 + 21.0 g 53.8 55.0 53.8 3.4 3204 Apron XL 3 LS + Maxim 4 FS 7.5 + 2.5 48.8 49.4 46.0 4.6 2360 + Systhane 40 WSP + 21.0 g Allegiance-FL + Baytan 30 15.0 + 10.0 50.0 47.4 51.2 4.2 3018 + Thiram 42-S + 31.0 g Allegiance-FL + Baytan 30 15.0 + 10.0 55.8 50.2 48.4 4.8 2725 + Thiram 42-S + 31.0 + Delta Coat AD 3.24 FS + 300.0 g Allegiance-FL + Baytan 30 15.0 + 10.0 43.2 43.2 39.4 3.8 3076 + Thiram 42-S + Azoxystrobin + 31.0 + 3.0 + Allegiance-FL + Baytan 30 + 15.0 + 5.0 g Allegiance-FL + Vitavax-PCNB 3.36 LS 15.0 + 176.0 45.8 47.6 44.0 4.6 2702 + Thiram 42-S + 31.0 g Azoxystrobin + Apron XL 3 LS 15.0 + 7.5 55.2 49.0 48.6 3.2 2783 + Maxim 4 FS + 2.5 g LSD P = (0.05) 10.3 12.3 14.9 2.3 1272 EVALUATION OF SELECTED SEED TREATMENTS FOR MANAGEMENT OF COTTON SEEDLING DISEASE IN CENTRAL ALABAMA K. S. McLean, A. J. Palmateer, J. L. Hutchinson, and D. Moore This cotton fungicide test evaluated selected seed treat- ments for management of cotton seedling disease. The test was planted on April 11 at the Prattville Agricultural Research Unit, Prattville, Alabama. The field had a history of cotton seed- ling disease and the soil type was a sandy loam. Soil tempera- ture was 65 0 F at a 4-inch depth at 10 a. m. with adequate mois- ture at planting. Fungicides were applied as a seed treatment by the manufacturer. Plots consisted of two rows, 30 feet long with a 36-inch wide row spacing and were arranged in a ran- domized complete block design with five replications. High dis- ease incidence plots were infested with millet seed inoculated with Pythium spp. and Rhizoctonia solani. Blocks were sepa- rated by a 20-foot alley. The nematicide Temik 15G (5 pounds per acre) was applied in-furrow at planting. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production prac- tices as recommended by the Alabama Cooperative Extension System. Stand counts and skip index ratings were recorded at 2, 4, and 6 weeks after planting to determine the percent seed- ling loss and stand density due to cotton seedling disease. Plots were harvested on September 10. Data were statistically analyzed by ANOVA and means compared using Fisher's pro- tected least significant difference test (P=0.05). Cotton seedling disease incidence was moderate in cen- tral Alabama in 2002 due to cold dry weather. In the high dis- ease incidence plots, differences (P< 0.05) in seedling stand were observed at 2, 4, and 6 weeks after planting (Table 1). At 2, 4, and 6 weeks after planting, all seed treatments improved seedling survival an average of 64% as compared to the con- trol at 27%. A lower skip index (Ps< 0.05), indicating a more evenly spaced seedling stand, was observed at 6 weeks after planting in all seed treatments. Three seed treatments-Al 3012 FS 125, Allegiance-FL plus Baytan 30 plus Thiram 42, and Alle- giance-FL plus Baytan 30 plus Thiram 42-S plus Azoxystrobin plus Allegiance-FL plus Baytan 30-increased yields over the control (P< 0.05). The average yield of seed cotton from all fungicide-treated plots was 162 pounds per acre greater than the untreated control. Under low disease pressure, stand was not increased by any seed treatment compared to the control at 2, 4, or 6 weeks after planting (Table 2). The average seedling 42 ALABAMA AGRICULTURAL ExPERIMENT STATION 2002 COrrTON RESEARCH REPORT 43 survival for the seed treatments was 79% compared to 80% in 4 FS plus Systhane 40 WSP seed treatments. No seed treat- the control. A higher skip index (P< 0.05), indicating an un- ment increased yields over the control (P< 0.05) under low dis- evenly spaced seedling stand, was observed at 6 weeks after ease pressure. planting in the A13012 FS 125 and Apron XL 3 LS plus Maxim TABLE 1. EFFECT OF SELECTED SEED TREATMENTS ON COTTON STAND, SKIP INDEX, AND SEED COTTON YIELD UNDER HIGH DISEASE PRESSURE IN CENTRAL ALABAMA Treatment Rate a.i./100 kg seed Stand 25 ft row Skip index Seed cotton 14 DAP 28 DAP 42 DAP lb/ac Control - 32.2 f 32.3 f 31.8 f 10.8 a 2766 b A13012 FS 125 25.0 g 65.2 de 72.2 de 60.0 de 6.8 bc 2887 ab A13012 FS 125 25.0 g 73.8 cd 78.0 cd 72.2 bcd 2.8 d 3029 a A13012 FS 125 25.0 g 76.0 cd 77.0 cd 77.6 bc 4.5 cd 2920 ab A13012 FS 125 + Systhane 40 WSP 25.0 + 21.0 g 95.5 ab 96.3 ab 102.5 a 2.8 d 2904 ab A13012 FS 125 + Systhane 40 WSP 25.0 + 21.0 g 79.3 cd 88.2 a-d 83.2 b 4.5 cd 2920 ab A13012 FS 125 + Systhane 40 WSP 25.0 + 21.0 g 84.5 bc 89.7 abc 82.5 b 4.0 cd 2879 ab Apron XL 3 LS + Maxim 4 FS 7.5 + 2.5 72.0 cd 72.5 de 66.0 cde 6.5 bc 2908 ab + Systhane 40 WSP + 21.0 g Allegiance-FL + Baytan 30 15.0 + 10.0 72.3 cd 73.2 cde 68.8 bcd 4.8 cd 2980 a + Thiram 42-S + 31.0 g Allegiance-FL + Baytan 30 15.0 + 10.0 103.6 a 104.2 a 101.0 a 2.7 cd 2908 ab + Thiram 42-S S + 31.0 + Delta Coat AD 3.24 F + 300.0 g Allegiance-FL + Baytan 30 15.0 + 10.0 78.3 cd 78.5 cd 78.3 bc 4.5 cd 3016 a + Thiram 42-S + Azoxystrobin + 31.0 + 3.0 + Allegiance-FL + Baytan 30 + 15.0 + 5.0 g Allegiance-FL + Vitavax-PCNB 3.36 LS 15.0 + 176.0 72.5 cd 82.0 bcd 70.5 bcd 3.7cd 2936 ab + Thiram 42-S + 31.0 g Azoxystrobin + Apron XL 3 LS 15.0 + 7.5 53.3 e 57.2 e 51.17 8.7ab 2859 ab + Maxim 4 FS + 2.5 g LSD P = (0.05) 14.4 16.7 14.8 3.3 200 TABLE 2. EFFECT OF SELECTED SEED TREATMENTS ON COTTON STAND, SKIP INDEX, AND SEED COTTON YIELD UNDER Low DISEASE PRESSURE IN CENTRAL ALABAMA Treatment Rate a.i./100 kg seed Stand 25 ft row Skip index Seed cotton 14 DAP 28 DAP 42 DAP Ib/ac Control 98.3 abc 95.1 bc 100.1 a-d 1.0 c 3182 a A13012 FS 125 25.0 g 85.6 cd 90.5 bc 93.3 bcd 1.0 c 3061 abc A13012 FS 125 25.0 g 107.8 a 107.2 ab 114.6 a 1.8 bc 3101 abc A13012 FS 125 25.0 g 84.5 d 96.0 bc 98.8 a-d 3.3 ab 3105 abc A13012 FS 125 + Systhane 40 WSP 25.0 + 21.0 g 89.5 cd 116.3 a 110.0 ab 2.2 abc 2948 c A13012 FS 125 + Systhane 40 WSP 25.0 + 21.0 g 92.8 bcd 84.5 c 94.2 bcd 1.8 bc 3016 abc A13012 FS 125 + Systhane 40 WSP 25.0 + 21.0 g 96.0 a-d 94.3 bc 106.0 abc 2.0 abc 2978 bc Apron XL 3 LS + Maxim 4 FS 7.5 + 2.5 93.0 bcd 87.3 c 89.0 d 3.5 a 3012 abc + Systhane 40 WSP + 21.0 g Allegiance-FL + Baytan 30 15.0 + 10.0 87.0 cd 93.2 bc 96.7 bcd 1.8 bc 3105 abc + Thiram 42-S + 31.0 g Allegiance-FL + Baytan 30 15.0 + 10.0 98.3 abc 97.5 bc 87.5 d 1.6 c 2980 bc + Thiram 42-S + 31.0 + Delta Coat AD 3.24 FS + 300.0 g Allegiance-FL + Baytan 30 15.0 + 10.0 90.7 bcd 86.0 c 95.6 bcd 2.2 abc 3000 abc + Thiram 42-S + Azoxystrobin + 31.0 + 3.0 + Allegiance-FL + Baytan 30 + 15.0 + 5.0 g Allegiance-FL + Vitavax-PCNB 3.36 LS 15.0 + 176.0 91.7 bcd 93.3 bc 92.6 cd 2.3 abc 3101 abc + Thiram 42-S + 31.0 g Azoxystrobin + Apron XL 3 LS 15.0 + 7.5 103.2 ab 104.8 ab 94.3 bcd 1.5 c 3154 ab + Maxim 4 FS + 2.5 g LSD P = (0.05) 13.5 16.8 16.9 1.6 201 ALABAMA AGRICULTURAL EXPERIMENT STATION EVALUATION OF SELECTED IN-FURROW FUNGICIDES FOR MANAGEMENT OF COTTON SEEDLING DISEASE IN CENTRAL ALABAMA K. S. McLean, A. 3. Palmateer, J. L. Hutchinson, and B. E. Norris This cotton fungicide test evaluated Terraclor Super X, Ridomil Gold, Quadris 4F, Rovral 4F, Delta Coat AD, and Mes- senger for the management of cotton seedling disease. This cotton fungicide test was planted on April 11 at the Prattville Agricultural Research Unit, Prattville, Alabama. The field had a history of cotton seedling disease and the soil type was a sandy loam. Soil temperature was 65 0 F at a 4-inch depth at 10 a. m. with adequate moisture at planting. Fungicides were applied as a seed treatment or as an in-furrow or spray or granular applica- tion at planting. All in-furrow fungicide sprays were applied with flat tip 8002E nozzles calibrated to deliver 6 gallons per acre at 18 pounds per square inch. In-furrow granular applica- tions were applied with chemical granular applicators attached to the planter. 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 five replications. High disease inci- dence plots were infested with millet seed inoculated with Pythium spp. and Rhizoctonia solani. Blocks were separated by a 20-foot alley. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production prac- tices as recommended by the Alabama Cooperative Extension System. Stand counts and skip index ratings were recorded at 2, 4, and 6 weeks after planting to determine the percent seed- ling loss and stand density due to cotton seedling disease. Plots were harvested on September 10. Data were statistically analyzed by ANOVA and means compared using Fisher's pro- tected least significant difference test (P=0.05). Cotton seedling disease incidence was moderate in cen- tral Alabama in 2002 due to cold dry weather. In the high dis- ease incidence plots, differences (P< 0.05) in seedling stand were observed at 2, 4, and 6 weeks after planting (Table 1). Rovral increased plant stand while Ridomil Gold EC, Ridomil Gold G, and Messenger decreased plant stand as compared to the control at 2, 4, and 6 weeks after planting. A lower skip index (P< 0.05), indicating a more evenly spaced seedling stand, was observed at 6 weeks after planting in the Quadris treat- ment. Rovral increased yield by 189 pounds of seed cotton per acre as compared to the control. Under low disease pressure, stand was not increased by any fungicide treatment as com- pared to the control at 2, 4, or 6 weeks after planting (Table 2). The average seedling survival for the fungicide treatments was 65% compared to 86% in the control. No differences in the skip index (P< 0.05) were observed between any fungicide treat- ment and the control. Rovral increased seed cotton yield by 371 pounds of seed cotton per acre as compared to the control. TABLE 1. EFFECT OF SELECTED FUNGICIDES ON COTTON STAND, SKIP INDEX, AND SEED COTTON YIELD UNDER HIGH DISEASE PRESSURE IN CENTRAL ALABAMA Treatment Rate Stand 25 ft row Skip index Seed cotton 14 DAP 28 DAP 42 DAP lb/ac Control - 103 bc 98 b 97 b 4.0 cd 2622 ab Terraclor Super X 18.8 G 5.0 lb/ac 91 cd 68 c 70 c 6.6 b 2472 bcd Terraclor Super X EC 48.0 oz/ac 125 ab 105 ab 111 ab 1.6 de 2557 bc Quadris 4F 6.0 oz/ac 120 ab 118 ab 120 ab 1.0 e 2565 bc Delta Coat AD 11.75 oz/cwt 124 ab 107 ab 117 ab 2.8 de 2545 bc AGST 01001 8.82 oz/cwt 111 abc 115 ab 112 ab 2.8 de 2492 bcd Ridomil Gold EC 1.0 oz/ac 73 de 70 c 66 c 8.5 ab 2368 cd Quadris 4 F + Ridomil Gold 6.0 oz/ac + 1.0 oz/ac 125 ab 120ab 118 ab 2.2 de 2573 bc Rovral 4F 6.0 oz/ac 133 a 124 a 123 a 1.6 de 2811 a Ridomil Gold G 5.0 Ib/ac 74 de 74 c 67 c 6.5 bc 2476 bcd Messenger 2.25 oz/ac 58 e 42 d 46 c 10.2 a 2319 d LSD P=(0.05) 25.0 22.2 24.5 2.6 207 44 2002 COTTON RESEARCH REPORT 45 TABLE 2. EFFECT OF SELECTED FUNGICIDES ON COTTON STAND, SKIP INDEX, AND SEED COTTON YIELD UNDER Low DISEASE PRESSURE IN CENTRAL ALABAMA Treatment Rate - Stand 25 ft row Skip index Seed cotton 14 DAP 28 DAP 42 DAP lb/ac Control - 137 ab 130 129 a 1.0 ab 2573 b Terraclor Super X 18.8 G 5.0 lb/ac 118 bc 124 123 ab 1.1 ab 2561 b Terraclor Super X EC 48.0 oz/ac 123 abc 126 131 a 3.0 a 2500 b Quadris 4F 6.0 oz/ac 140 ab 114 130 a 2.3 ab 2508 b Delta Coat AD 11.75 oz/cwt 109c 129 105 b 1.6 ab 2517 b AGST 01001 8.82 oz/cwt 137 ab 137 128 a 1.1 ab 2553 b Ridomil Gold EC 1.0 oz/ac 122 abc 118 121 ab 1.8 ab 2573 b Quadris 4 F + Ridomil Gold 6.0 oz/ac + 1.0 oz/ac 142 a 131 130 a 1.6 ab 2528 b Rovral 4F 6.0 oz/ac 117 bc 125 120 ab 1.6 ab 2944 a Ridomil Gold G 5.0 Ib/ac 126 abc 124 116 ab 0.6 b 2521 b Messenger 2.25 oz/ac 127 abc 123 122 ab 2.0 ab 2573 b LSD P=(0.05) 22.6 29.1 21.1 1.9 259 EVALUATION OF SELECTED IN-FURROW FUNGICIDES FOR MANAGEMENT OF RHIZOCTONIA SOLANI SEEDLING K. S. McLean, A. J. Palmateer, J. L. Hutchinson, and D. Moore Terraclor 15Q Terraclor 2E, Quadris 4F, Rovral 4F, and Delta Coat AD were evaluated for management of cotton seedling disease caused by Rhizoctonia solani. This cotton fungicide test was planted on April 11 at the Prattville Agricultural Re- search Unit, Prattville, Alabama. The field had a history of cot- ton seedling disease and the soil type was a sandy loam. Soil temperature was 65 0 F at a 4-inch depth at 10 a. m. with adequate moisture at planting. Fungicides were applied as a seed treat- ment or as an in-furrow or spray application at planting. All in- furrow fungicide sprays were applied with flat-tip 8002E nozzles calibrated to deliver 6 gallons per acre at 18 pounds per square inch. 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 five replications. High disease incidence plots were infested with millet seed inoculated with Pythium spp. and Rhizoctonia solani. Blocks were separated by a 20-foot alley. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production prac- tices as recommended by the Alabama Cooperative Extension System. Stand counts and skip index ratings were recorded at DISEASE IN CENTRAL ALABAMA 2, 4, and 6 weeks after planting to determine the percent seed- ling loss and stand density due to cotton seedling disease. Plots were harvested on September 10. Data were statistically analyzed by ANOVA and means compared using Fisher's pro- tected least significant difference test (P=0.05). Cotton seedling disease incidence was moderate in cen- tral Alabama in 2002 due to cold dry weather. In the high dis- ease incidence plots, differences (P< 0.05) in seedling stand were observed at 2, 4, and 6 weeks after planting (Table 1). Quadris, Rovral, and Delta Coat AD increased plant stand as compared to the control at 2, 4, and 6 weeks after planting. A lower skip index (P< 0.05), indicating a more evenly spaced seedling stand, was observed at 6 weeks after planting in the Rovral treatment. Rovral and Quadris increased yield by 218 and 182 pounds of seed cotton per acre as compared to the control. Under low disease pressure, stand was not increased by any fungicide treatment as compared to the control at 2, 4, or 6 weeks after planting (Table 2). No differences in the skip index (P< 0.05) were observed between any fungicide treat- ment and the control. The average yield of seed cotton from all fungicide-treated plots was 18 pounds per acre greater than the control. TABLE 1. EFFECT OF FUNGICIDES ON COTTON STAND, SKIP INDEX, AND SEED COTTON YIELD UNDER HIGH DISEASE PRESSURE IN CENTRAL ALABAMA Treatment Rate Stand 25 ft row Skip index Seed cotton 14 DAP 28 DAP 42 DAP Ib/ac Control - 77.5 c 72.2 b 73.7 b 4.3 a 2686 c Terraclor 15G 5.0 lb/ac 101.5 ab 104.3 a 91.8 ab 2.3 ab 2755 bc Terraclor 2E 48.0 oz/ac 88.6 bc 96.0 ab 83.8 ab 4.0 ab 2690 c Quadris 4F 6.0 oz/ac 108.5 ab 112.3 a 101.8 a 2.0 ab 2904 a Rovral 4F 6.0 oz/ac 115.5 a 99.8 a 97.0 a 1.7 b 2868 a Delta Coat AD 11.75 oz/cwt 120.6 a 106 a 99.2 a 3.7 ab 2791 bc LSD P= (0.05) 22.9 26.9 20.4 2.5 140 TABLE 2. EFFECT OF FUNGICIDES ON COTTON STAND, SKIP INDEX, AND SEED COTTON YIELD UNDER Low DISEASE PRESSURE IN CENTRAL ALABAMA Treatment Rate Stand 25 ft row Skip index Seed cotton 14 DAP 28 DAP 42 DAP Ib/ac Control 119.8 a 110.0 a 108.0 a 2.2 a 2629 Terraclor 15G 5.0 Ib/ac 107.5 a 124.7a 125.7 a 1.8 a 2573 Terraclor 2E 48.0 oz/ac 107.3 a 121.0 a 112.5 a 2.7 a 2698 Quadris 4F 6.0 oz/ac 117.3 a 114.7 a 113.7 a 2.7 a 2621 Rovral4F 6.0 oz/ac 123.3 a 118.3 a 111.7 a 2.0a 2682 Delta Coat AD 11.75 oz/cwt 125.3 a 125.7 a 115.0 a 1.7 a 2682 LSD P= (0.05) 18.4 28.2 21.9 2.3 131 EVALUATION OF SELECTED IN-FURROW FUNGICIDES FOR MANAGEMENT OF COTTON SEEDLING DISEASE IN NORTH ALABAMA K. S. McLean, A. 3. Palmateer, 3. L. Hutchinson, and B. E. Norris This cotton fungicide test evaluated Terraclor Super X, Ridomil Gold, Quadris 4F, Rovral 4F, Delta Coat AD, Messen- ger, and FAC 321 for the management of cotton seedling dis- ease. The test was planted on April 15 at the Tennessee Valley Research and Extension Center, Belle Mina, Alabama. The field had a history of cotton seedling disease and the soil type was a Decatur silty loam. Soil temperature was 65 0 F at a 4-inch depth at 10 a. m. with adequate moisture at planting. Fungicides were applied as a seed treatment or as an in-furrow or spray or granular application at planting. All in-furrow fungicide sprays were applied with flat-tip 8002E nozzles calibrated to deliver 6 gal- lons per acre at 18 pounds per square inch. In-furrow granular applications were applied with chemical granular applicators attached to the planter. 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 inocu- lated with Pythium spp. and Rhizoctonia solani. Blocks were separated by a 20-foot alley. The nematicide Temik 15G (5 pounds per acre) was applied in-furrow at planting. All plots were maintained throughout the season with standard herbicide, insecticide, and fertility production prac- tices as recommended by the Alabama Cooperative Extension System. Stand counts and skip index ratings were recorded at 2, 4, and 6 weeks after planting to determine the percent seed- ling loss and stand density due to cotton seedling disease. Plots were harvested on September 24. Data were statistically analyzed by ANOVA and means compared using Fisher's pro- tected least significant difference test (P < 0.05). Cotton seedling disease incidence was severe in 2002 due to cold wet weather. In the high disease incidence plots, differences (P< 0.05) in seedling stand were observed at 2, 4, and 6 weeks after planting (Table 1). At 2, 4, and 6 weeks after planting, three fungicide treatment stands were reduced com- pared to the control. A higher skip index (P< 0.05), indicating an unevenly spaced seedling stand, was observed at 6 weeks af- ter planting in the Delta Coat AD seed treatment as compared to the control. No fungicide treatment increased yields over the control (P< 0.05). The average yield of seed cotton from all fungicide-treated plots was 41 pounds per acre less than the 46 ALABAMAAGRICULTURAL ExPERIMENT STATION untreated control. Under low disease pressure, at 2, 4, and 6 AD and TSX 18.8G treatments as compared to the control. No weeks after planting, fungicide treatment stands were not dif- fungicide treatment increased yields over the control (P< 0.05). ferent from the control (Table 2). Correspondingly, a higher No fungicide treatment yielded more seed cotton per acre than skip index (P< 0.05), indicating an unevenly spaced seedling the control under either high or low disease pressure. stand, was observed at 6 weeks after planting in the Delta Coat TABLE 1. EFFECT OF SELECTED FUNGICIDES ON COTTON STAND, SKIP INDEX, AND SEED COTTON YIELD UNDER HIGH DISEASE PRESSURE IN NORTH ALABAMA Treatment Rate - Stand 25 ft row Skip index Seed cotton 14 DAP 28 DAP 42 DAP lb/ac Control - 88.6 a 92.2 a 88.0 ab 1.8 b 3353 a Terraclor Super X 18.8 G 5.0 Ib/ac 69.8 bc 75.4 a-d 70.4 cb 3.0 ab 3384 ab Terraclor Super X EC 48.0 oz/ac 82.8 ab 88.0abc 81.8 a 2.0 ab 3394 ab Quadris 4F 6.0 oz/ac 76.0 abc 74.4 bcd 78.8 abc 2.4 ab 3374 ab Delta Coat AD 11.75 oz/cwt 67.0 c 65.4 d 68.5 c 4.2 a 3340 ab AGST 01001 8.82 oz/cwt 78.6 abc 84.2 abc 78.8 abc 3.0 ab 3170 ab Ridomil Gold EC 1.0 oz/ac 82.0 ab 81.6 a-d 78.6 abc 3.4 ab 3313 ab Quadris 4 F + Ridomil Gold 6.0 oz/ac + 1.0 oz/ac 86.8 a 90.2 ab 89.8 a 2.4 ab 3455 a Rovral 4F 6.0 oz/ac 75.2 abc 77.6 a-d 72.8 abc 3.4 ab 3138 b Ridomil Gold G 5.0 Ib/ac 70.4 bc 71.2 cd 72.0 bc 2.2 ab 3321 ab Messenger 2.25 oz/ac 84.0 ab 79.0 a-d 65.8 c 3.4 ab 3222 ab FAC 321 2.0 fl oz/ac 88.8 a 85.4 abc 78.8 abc 2.2 ab 3272 ab FAC 321 + Terraclor 2E 2.0 + 48 fl oz/ac 78.8 abc 81.2 a-d 77.2 abc 3.2 ab 3363 ab LSD P < (0.05) 14.8 17.6 17.3 2.2 295 TABLE 2. EFFECT OF SELECTED FUNGICIDES ON COTTON STAND, SKIP INDEX, AND SEED COTTON YIELD UNDER Low DISEASE PRESSURE IN NORTH ALABAMA Treatment Rate -Stand 25 ft row Skip index Seed cotton 14 DAP 28 DAP 42 DAP Ib/ac Control - 94.6 ab 106.2 a 110.6 a 1.0 c 3868 a Terraclor Super X 18.8 G 5.0 lb/ac 77.4 c-f 72.8 c-f 78.8 cd 3.2 ab 3721 ab Terraclor Super X EC 48.0 oz/ac 96.4 a 93.0 ab 101.6 ab 1.2 bc 3708 ab Quadris 4F 6.0 oz/ac 82.4 b-e 85.2 bcd 85.2 bcd 1.6 bc 3773 ab Delta Coat AD 11.75 oz/cwt 72.2 def 70.0 ef 70.2 d 4.0 a 3578 ab AGST 01001 8.82 oz/cwt 87.6 abc 88.6 b 93.6 abc 2.0 abc 3585 ab Ridomil Gold EC 1.0 oz/ac 92.0 ab 88.6 b 89.8 bcd 1.4 bc 3607 ab Quadris 4 F + Ridomil Gold 6.0 oz/ac + 1.0 oz/ac 86.8 abc 86.4 bcd 83.8 bcd 1.6 bc 3692 ab Rovral 4F 6.0 oz/ac 69.2 f 68.0 f 77.4 cd 2.4 abc 3656 ab Ridomil Gold G 5.0 Ib/ac 70.2 ef 72.0 def 79.4 cd 3.0 abc 3753 ab Messenger 2.25 oz/ac 84.6 a-d 83.0 b-e 92.6 abc 1.2 bc 3577 ab FAC 321 2.0 fl oz/ac 83.8 a-d 81.2 b-e 81.4 cd 2.8 abc 3507 b FAC 321 + Terraclor 2E 2.0 + 48 fl oz/ac 91.0 ab 87.2 bc 86.8 bcd 1.8 bc 3562 ab LSD P < (0.05) 13.2 14.6 19.9 2.1 307 *Skip index is the accumulative value to every one foot space between plants. 2002COTTONRESEARCHREPORT 47 ALABAMA AGRICULTURAL EXPERIMENT STATION EVALUATION OF SELECTED IN-FURROW FUNGICIDES FOR MANAGEMENT OF RHIZOCTONIA SOLANI SEEDLING K. S. McLean, A. J. Palmateer, 3. L. Hutchinson, and B. E. Norris Terraclor 15G, Terraclor 2E, Quadris 4F, Rovral 4F, and Delta Coat AD were evaluated for management of cotton seed- ling disease caused by Rhizoctonia solani. This cotton fungi- cide test was planted on April 15 at the Tennessee Valley Re- search and Extension Center, Belle Mina, Alabama. The field had a history of cotton seedling disease and the soil type was a Decatur silty loam. Soil temperature was 65 0 F at a 4 inch depth at 10 a. m. with adequate moisture at planting. Fungicides were applied as a seed treatment or as an in-furrow spray at planting. All in-furrow fungicide sprays were applied with flat tip 8002E nozzles calibrated to deliver 6 gallons per acre at 18 pounds per square inch. Plots consisted of two rows, 25 feet long with a 40 inch wide row spacing and were arranged in a randomized com- plete block design with five replications. High disease inci- dence plots were infested with millet seed inoculated with Rhizoctonia solani. Blocks were separated by a 20-foot alley. The nematicide Temik 15G (5 pounds per acre) was applied in- furrow at planting. All plots were maintained throughout the season- with standard herbicide, insecticide, and fertility production prac- tices as recommended by the Alabama Cooperative Extension System. Stand counts and skip index ratings were recorded at DISEASE IN NORTH ALABAMA 2, 4, and 6 weeks after planting to determine the percent seed- ling loss and stand density due to cotton seedling disease. Plots were harvested on September 24. Data were statistically analyzed by ANOVA and means compared using Fisher's pro- tected least significant difference test (P < 0.05). Cotton seedling disease incidence was high in 2002 due to cold wet weather. In the high disease incidence plots, differ- ences (P< 0.05) in seedling stand were observed at 2, 4, and 6 weeks after planting (Table 1). At 2 weeks after planting, stands in three fungicide treatments were reduced compared to the control; however, by 4 and 6 weeks the stand was reduced only in the Rovral treatment. Correspondingly, a higher skip index (P< 0.05), indicating an unevenly spaced seedling stand, was observed in the Rovral treatment as compared to the control. No fungicide treatment produced yields higher than those pro- duced by the control (P< 0.05). Under low disease pressure, Terraclor 2E produced a reduced stand compared to the con- trol. No stand or skip index differences were observed at 6 weeks after planting (Table 2). No fungicide treatment produced yields higher than those produced by the control (P< 0.05). The yield was lower in the Rovral fungicide treatment under high and low disease pressure as compared to the control. TABLE 1. EFFECT OF FUNGICIDES ON COTTON STAND, SKIP INDEX, AND SEED COTTON YIELD UNDER HIGH DISEASE PRESSURE IN NORTH ALABAMA Treatment Rate - Stand 25 ft row Skip index Seed cotton 14 DAP 28 DAP 42 DAP /b/ac Control - 71 a 75 a 78 a 2.6 b 3745 a Terraclor 15G 5.0 lb/ac 69 abc 72 a 79 a 3.0 b 3648 a Terraclor 2E 48.0 oz/ac 65 bc 71 a 75 a 2.4 b 3635 a Quadris 4F 6.0 oz/ac 79 a 82 a 89 a 2.0 b 3865 a Rovral4F 6.0 oz/ac 56 c 41 b 39 b 10.0 a 3280 b Delta Coat AD 11.75 oz/cwt 65 bc 68 a 73 a 3.2 b 3713 a LSD P < (0.05) 13.8 16.8 20.0 2.9 298 TABLE 2. EFFECT OF FUNGICIDES ON COTTON STAND, SKIP INDEX, AND SEED COTTON YIELD UNDER Low DISEASE PRESSURE IN NORTH ALABAMA Treatment Rate Stand 25 ft row Skip index Seed cotton 14 DAP 28 DAP 42 DAP lb/ac Control 78 a 83 84 1.6 a 3964 a Terraclor 15G 5.0 Ib/ac 71 ab 77 75 2.8 a 3774 ab Terraclor 2E 48.0 oz/ac 64 b 79 78 2.6 a 3674 ab Quadris 4F 6.0 oz/ac 78 ab 77 82 2.4 a 3740 ab Rovral 4F 6.0 oz/ac 77 ab 83 81 1.2 a 3669 b Delta Coat AD 11.75 oz/cwt 72 ab 75 77 2.2 a 3729 ab LSD P < (0.05) 13.7 17.6 21.8 1.9 291 *Skip index is the accumulative value to every one foot space between plants. 48 2002 COTTON RESEARCH REPORT MOLECULAR STUDIES DEVELOPING IN VITRO COTTON CULTURE SYSTEMS FOR RENIFORM NEMATODE STUDIES Dewang Deng, Allan Zipf, Govind Sharma, Celeste Bell, Kara Harris, Dedrick Davis, and Yonathan Tilahun Reniform nematodes (Rotylenchulus reniformis) have be- come an extremely serious threat to Alabama cotton producers with their continued spread into uninfected cotton production areas. However, studying infection or resistance processes is difficult in the field or even under greenhouse conditions. Plant tolerance and susceptibility to reniform nematodes could be studied in in vitro cotton root cultures; however, excised root cultures have not been successful in earlier investigations, hence the critical need for the present study. The objectives of this project are (1) to develop long-term (at least 30 day) cotton root cultures, (2) to sterilize viable reniform nematodes, and (3) to establish continuous reniform infections in the root cultures. As a complement to the successful root culture system, achieved by Deng in 2002, researchers are proceeding to ster- ilize viable reniform nematodes. In addition, they are working to develop successful solid root cultures for ease of mainte- nance and setup. Various antiseptic treatments and treatment lengths are being investigated in order to maximize sterilization while still keeping the nematodes alive. Sterilizing agents, which include Clorox, hydrogen peroxide, and mercuric chloride, are being tested to determine the minimal effective dose. Semi-solid media, made with different gelling agents, are also being investigated as a means for more easily viewing the infec- tion process. However, an appropriate medium recipe for success- ful cotton root development has not yet been found. ISOLATION OF GENES RELATED TO COTTON FIBER DEVELOPMENT Khairy Soliman, Allan Zipf, Govind Sharma, Zhengdao Wu, and James Bolton An important objective of cotton research at Alabama A&M University is to reveal genes that may have roles in either cotton growth or fiber quality. A number of projects try- ing to find genes associated with various aspects of cotton culture are being conducted through a diverse set of active collaborators. Two of these projects will be discussed in this article. Identification of genes related to cotton fiber develop- ment using unique mutants. In collaboration with Dr. Sukumar Saha, researchers are studying the Li-1 mutant fiber develop- ment. Short fiber and distorted stems and leaves characterize this mutant. Using Simple Sequence Repeat primers, research- ers have found no obvious differences (polymorphisms) when separating polymerase chain reaction (PCR) fragments on aga- rose gels. The fragments are being cloned and will be sequenced on a ABI 3100 Sequencer to analyze for single DNA base pair differences (SNPs - Single Nucleotide Polymorphisms). These sequences can then be used to give unique markers, which can be used to screen the F 2 population to make a genetic map. Identification of fiber-related genes by differential screen- ing. Another project aims to identify cotton genes associated with fiber quality. This project uses high yielding Upland cot- ton, TM-1, and high fiber quality Pima cotton, 3-79. Five clones showing high expression in 20 day postanthesis (dpa) fiber tissue of 3-79 cotton were used as probes in Northern blotting of roots, leaves, flowers and fibers of different developmental stages. Northern analysis showed that the expression of the five cDNA clones was developmentally regulated and not tis- sue-specific (see figure). The genes for all the five cDNAs showed much higher expression levels in the fiber than in the other tissues tested with the exception of the gene for GbFb, in the flower. Four of the five genes were highly expressed in the early stage of fiber development (10 to 15 dpa) in both 3-79 and TM-1 fibers. The expression of these genes appeared to peak at about 15 dpa and then decreased sharply after 20 dpa. How- ever, the expression pattern of the gene for GbMAPK steadily increased in 3-79 immature fibers during primary wall synthesis (about 10 to 15 dpa), reached a maximum at about 20 dpa, and 49 UIILIIHIC ~1~ ~~~V ~IYIU V1 VI VII HIIUVI k~VVIIIIVHUV VVI~UI~IVIIV ~ ICCLL~ IICCIIVV ~CIIU VVCUC/ ALABAMA AGRICULTURAL EXPERIMENT STATION declined after 25 dpa. On the other hand, the expression level for GbN'IAPK in TM- I fibers was very low at about 10 dpa, but showed a peak at about 15 dpa and decreased sharply after 20 dpa. Several clones are also being Investigated for their pattern of expression to try to identify those genes associated with the yield or fiber quality. Expression pattern of the five cDNA clones in different tissues of 3-79 and developing fibers of 3-79 and TM-i plants. Two independent Northern blots (A and B), with 30 mg of total RNA in each lane, were sequentially hybridized with the cDNA probes indicated. The loading differences in each lane were as- sessed by hybridization with an 18S rRNA probe from Ara/idopsis. Note: R = roots; L = leaves; F = flowers. U R L 3-79 TM-I F 10 15 20 25 Blank 25 20 15 14) GAFh, Gbueri bl ryu I' L1'L 3-79 TM-i m ~R L F 10 15 20 25 Blank 25. 20 15 10 GbMAPK I p;; 1IS rRNA GENETIC VARIATION IN RENIFORM NEMATODE POPULATIONS Yonathan Tilahun,, Dewang Deng, Allan Zipf, Govind Sharma, Celeste Bell, Kara Harris, Dedrick Davis, K. McLean, and J. Jenkins Solutions to the threat of reniform nematodes (Rotylenchulus reniformis) will depend on the genetic varia- tion (races) within the species. If the populations are uniform, then control measures may be applicable across large regions. If, however, significant variability exists, then control measures may only be effective for small populations or even sub-groups within a population. Knowing how uniform reniform nematode populations are is a critical first step before effective control measures can be undertaken. Nematodes were collected from nine locations in six Ala- bama counties, spanning the northern and southern borders of Alabama (see table). The samples were obtained through the Tennessee Valley Research and Extension Center, Belle Mina, Alabama,with the cooperation of Charlie Burmester, and the 50 - 2002 COTTONRESEARCH REPORT Plant Diagnostics Laboratory through the Alabama Coopera- tive Extension System at Auburn University with the coopera- tion of Ms. Kristie Siggers. Reniform nematode population variation, not apparent from 18S rDNA primer polymerase chain reaction (PCR) bands, was detected only by sequencing and single nucleotide poly- morphism analysis. Genomic differences were found, not only between different populations from different locations, but even within the populations from the same location (see figure). This high variability may be due to high genetic variability between individuals, a paradox since rRNA is considered to be "highly conserved." Another explanation may be that numerous ge- netically different introductions of reniform nematode were made by farm equipment, soil sampling, runoff, etc., through- out the region, resulting in established diverse populations. This is the first report of any sequence information from Rotylenchulus reniformis, the reniform nematode. NEMATODE POPULATION SAMPLING SITES County Farm Designation Limestone Unknown LL Limestone Anderson AL Lawrence Haney LH Lawrence Posey LP Morgan Collins MC Escambia Unknown EC Autauga Unknown AC Colbert Underwood CU Phylogram of 18S clone sequences. First two letters of each clone correspond to location of reniform infested soil samples as per table. La-IOSII-734 -- LCb-18Sf1-734 LC3-18S11-734 ACS- IOSII-734 EC4-lOSrevfl-734 LP9-IOSII-734 LH3-IOSII-734 LPIOSI/1-734 - ACI-ISII-734 EC9-18S11-734 EC-IgSfl;-734A LPb-IOSII-734 A H2-OS/1-734 7 MCISS-2fl-734 14EC3b-lBSrevfI-734 LP7-lOSrevfl-734 LH7-18M-734 AC3-lOSrevfl-734 MC-ISI-734o/173 LCIO-18S/1-7344 AC-OSrv/l-734 A- WfSrevS-734 LC 0-BSrev-7343 LC7-18Sev1--34 EC6-18Sre1-734 LP 7b-18S11-7343 LLPIO-18S1--73 LC6-lOSreM-734 E!de ---- lP3-IOSII-73-734 rPIO e8SM-73 LCb-OSrevl-734 C2-l8Sav7-73 MI8IS-41-734 LCO6-ISr"I-73 A2-18S1-734 ECIO18S1-73473 18SO-3 l-734 AIlCIrevSl-734 EC8-18S11-7344 LH5-lOOrev1l-7J LH4-18S11-734 C AC7lB Lev l-734 evI- 3 LPCb-IOSII-734 ACIO-OSv-734 LC-8S1-734 LH5thereg Bnrevfl-734 stbise ivre ouatos U9-18S/1-73 51 52 ALABAMA AGRICULTURAL EXPERIMENT STATION AUTHORS' INDEX Author Page Author Page James R. Akridge James W. Baler Celeste Bell W.C. Birdsong James Bolton Charles Burmester Larry M. Curtis Dedrick Davis Dennis P. Delaney Dewang Deng David Derrick Bobby Durbin Wilson H. Faircloth Barry L. Freeman William S. Gazaway Kathy Glass Curtis Grissom Bob Goodman David H. Harkins Kara Harris J. L. Hutchinson J. Jenkins J. R. Jones G. W. Lawrence Kathy S. McLean B. A. Meyer Charles Mitchell C. Dale Monks Don R Moore 34,35,35-36 12-15 49,50-51 10-12,19-20,26-27 49-50 116-717-8,12-15,18,31 10-12,12-15 49,50-51 1-2,2-3,3,21-22,40 49,50-51 1 2-3,3 9-10 23-24,26 4,33,3435-36 1-2,2-33,44-55-638,39 31 40 12-15 49,50-51 4-5f,5-6,32,38,39,41-42f 42-43,44-45,45-46,46-47,48 50-51 4-5,5-6,32,36,39 4-5,5-632,39 4-55-6, 6-77-8,31, 32,36,39, 40,41-42,42-43,44-45,45-46f 46-47,4850-51 6-77-8 19-20,21-22,40 1-2,2-33,40 32,33f,37f42-43f,45-46 E. Z. Nyakatawa Bobby E. Norris Aaron Palmateer Michael G. Patterson M. D. Pegues K. C. Reddy D. W. Reeves Maria Rivas Govind Sharma J. N. Shaw Edward Sikora Ron H. Smith Khairy Soliman Yonathan Tilahun Kevan Tucker Ted Tyson S. R. Usery, Jr. E. van Santen James R. Weeks Larry W. Wells Anthony Wiggins Zhengdao Wu Rudy Yates Allan Zipf 16-17 12-15,37,41-42,4-54-47 48 4-55-632,38,39,41-42,42-43 44-45 ,45-46,46-47348 9-10 4-55-6,38,39 16-17 18,21 -22 37 49,49-50,50-51 18 37-40 28-30 49-50 49,50-51 40 10-12 6-737-8 6-737-8 26-27 37 1-2 49-50 40 49,49-50,50-51 ALABAMA AGRICULTURAL ExPERIMENT STATION52 Alabama's Agricultural Experiment Station System AUBURN UNIVERSITY Main Agricultural Experiment Station, Auburn. IMESTONE MADISON JACKSON Alabama A&M University " E. V. Smith Research Center, Shorter. MORGO MARSHALL DE KALB E 2 1. Tennessee Valley Research and ETOWAH CHEROKE Extension Center, Belle Mina 2. Sand Mountain Research and Extension ALHOUCenter, Crossville JEFFERSONSAINTCLAIR3. North Alabama Horticulture Research TALLEDEGA CLEBURNECenter, Cullman HELBY4. Upper Coastal Plains Agricultural Research Center, Winfield COOSA TALLAP CHAMBER 5. Chilton Area Research and Extension 5Center, Clanton ELMORE6. *Piedmont Substation, Camp Hill - U 7. Prattville Agricultural Research Unit, ONTGOMER MACON RUSSELL Prattville SUOCK8. Black Belt Research and Extension LLAS BARBOUR Center, Marion Junction BUTLER PIKE 9. Lower Coastal Plain Substation, HENRYCamden CRENSH COFFEE DALE 10. *Monroeville Agricultural Research Unit, S COVINGTON1 Monroeville HOUSTO 11. Wiregrass Research and Extension GENEVA Center, Headland 12. Brewton Agricultural Research Unit, Brewton 13. Ornamental Horticulture Research Center, Spring Hill 14. Gulf Coast Research and Extension Center, Fairhope *Temporarily inactive