Slide 1

2011 Beltwide: Managing glyphosate-resistant Palmer amaranth using 2,4-D systems in Dow AgroSciences Herbicide Trait Technology (DHT) Cotton In GA, NC, and TN. Culpepper, Steckel, York (UGA, UT, NCSU) Braxton and Richburg (Dow AgroSciences) Slide 2 Slide 3 Slide 4 York 2010 Hand Weeding Slide 5 York 2010 Hand Weeding Slide 6 DHT Cotton In Development by Dow AgroSciences DHT 2,4-D tolerant cotton 2,4-D sensitive cotton Slide 7 Objective Determine the most effective 2,4-D weed management systems for glyphosate- resistant Palmer amaranth in DHT cotton. Slide 8 Amaranthus rudis Amaranthus palmeri Tennessee Missouri Illinois Mississippi Georgia S Carolina N Carolina Alabama Louisiana Arkansas Glyphosate-Resistant Pigweed Species Steckel 2010 Slide 9 Tennessee Missouri Illinois Mississippi Georgia S Carolina N Carolina Alabama Louisiana Arkansas Experimental Locations GA Locations: completely resistant populations; NC and TN: mixed population. Slide 10 Experimental Treatments POST 1 (2-3 Palmer) 2,4-D 2,4-D + Ignite Ignite Durango 2,4-D + Durango POST 2 (4-9 Palmer) 2,4-D 2,4-D + Ignite Ignite Durango 2,4-D + Durango Total POST programs Direx + MSMA directed to all systems. 2,4-D = Weedar 34 oz/A; Ignite 29 oz/A; Direx 2 pt/A; MSMA 2 lb ai/A. A non-treated control was included. TRT 1 2 3 4 5 Durango - Dow AgroSciences, LLC Direx - Dupont Crop Protection Ignite - Bayer Crop Sciences LP Slide 11 Experimental Treatments POST 1 (2-3 Palmer) 2,4-D 2,4-D + Ignite 2,4-D + Durango POST 2 (4-8 Palmer) 2,4-D 2,4-D + Ignite 2,4-D + Durango Prowl and Reflex (SE) or Cotoran (TN) PRE Direx + MSMA directed to all systems. 2,4-D 34 oz/A; Ignite 29 oz/A; Direx and Cotoran 2 pt/A; MSMA 2 lb ai/A; Prowl H 2 0 34 oz. TRT 1 2 3 Prowl BASF Corporation Reflex Syngenta Crop Protection, Inc.Cotoran MANA - Makhteshim Agan of North America, Inc. Slide 12 Planting Dates: May 1 to May 6 First Activating Rainfall: GA1 = 2 d; GA 2 = 11 d; NC: 11 d; TN = 6 d Crop tolerance data not reported as technology still being developed. Slide 13 Percent Palmer amaranth control just prior to layby. GA1, GA2, TN, NC 2010. 74 c 85 b 43 d 86 b 93 a 99 a 2,4-D Dur. + D Durango Ignite Prowl POT 1 POT 2 IG + D 97 a 2,4-D Dur. + D IG + D Slide 14 Percent Palmer amaranth control just prior to layby in residual systems. GA1, GA2, TN, NC 2010. 93 b 99 a Prowl POT 1 POT 2 2,4-D Dur. + D IG + D Reflex or Cotoran 92 b93 b Reflex or Cotoran 93 b 99 a Slide 15 Durango fb Durango Palmer amaranth control just prior to layby. Macon Co., 2010. Slide 16 2,4-D fb 2,4-D 2,4-D + Ignite fb 2,4-D + Ignite Palmer amaranth control just prior to layby. Macon Co., 2010. Slide 17 Prowl fb 2,4-D twice Prowl fb 2,4-D + Ignite twice Palmer amaranth control just prior to layby. Macon Co., 2010. Slide 18 Percent Palmer amaranth control during late season. GA1, GA2, and NC 2010. 75 d 84 c 28 e 90 bc 95 ab 98 a 2,4-D Dur. + D Durango Ignite Prowl POT 1 POT 2 IG + D 97 a Direx + MSMA directed to all systems. 2,4-D Dur. + D IG + D Slide 19 Percent Palmer amaranth control just prior to layby in residual systems. GA1, GA2, NC 2010. 95 99 Prowl POT 1 POT 2 Direx + MSMA directed to all systems. 2,4-D Dur. + D IG + D Reflex 9695 Reflex 97 98 Slide 20 Slide 21 Seed Cotton Yield. GA1 and GA2, 2010. 759 b 855 b 242 c 876 b 1170 a 1115 a 1205 a 2,4-D Dur. + D Durango Ignite Prowl POT 1 POT 2 IG + D 1230 a Direx + MSMA directed to all systems. 2,4-D Dur. + D IG + D Slide 22 1170 1205 Prowl POT 1 POT 2 Direx + MSMA directed to all systems. 2,4-D Dur. + D IG + D Reflex 1230 1115 Reflex 12101205 Seed Cotton Yield. GA1 and GA2, 2010. Slide 23 Summary In total POST sequential systems: Ignite + 2,4-D > Dur. + 2,4-D > 2,4-D > Ignite > Dur. In 2,4-D systems, residual applications of Prowl were as effective as Reflex or Cotoran. All programs provided at least 93% control. Control of 99% only noted with systems including sequential Ignite + 2,4-D applications. Cotton yields greater with residual systems and in the total POST system with Ignite + 2,4-D. Slide 24 Conclusion Numerous weed management systems in DHT Cotton will effectively manage glyphosate-resistant Palmer amaranth Slide 25 Concerns Making it to 2015 or when commercialized? Sustainability of Ignite? Off target movement of 2,4-D research to address this concern is in progress Slide 26 2,4-D Ester 2,4-D Amine New Formulation N Slide 27 S SESW EW N NENW Potted cotton plants placed in all directions @ 5, 10, 20, 40, 80 and 160 ft 4 plants per station Volatility distance (plants placed in field after drift pots were removed) Slide 28 Temperature (F) Sept 9-11 Application Slide 29 Visual Injury 27 DAA from 2,4-D Volatility, October 6, 2010 Error bar is 1 Std error of mean Averaged across directions Entire 48 hrs Slide 30 Volatility Injury to Cotton: Tunnel/Dome Data John Richburg 2010 Project Review November, 2010 Slide 31 Visual Injury 27 DAA from 2,4-D Volatility under Tunnels (October 6, 2010) 20 19 13 00 4 6 Entire = 48 hrs T1 = 1 st 24 hrs T2 = 2 nd 24 hrs Slide 32 Comments?