2011 Glyphosate-Resistant Palmer Amaranth Management in Cotton - PowerPoint PPT Presentation

2011 Glyphosate-Resistant Palmer Amaranth Management in Cotton Culpepper, Steckel, York

GR Pigweed in the Mid-south and Southeast Illinois Missouri N Carolina Tennessee Arkansas S Carolina Mississippi Georgia m a A l a b a Louisiana Amaranthus rudis Amaranthus palmeri Steckel 2010

Managing GR Palmer in Cotton (Southeast and MidSouth) Weed Control Systems � Starting clean At-plant residuals Postemergence options Layby directed and hooded options � Roundup- and Ignite-based program � Building integrated programs Tillage, cover crops, etc

Preplant/PRE herbicides for Palmer amaranth in Roundup Ready Cotton in SE Preplant PRE Valor Direx

Controlling 5 inch Glyphosate-Resistant Palmer amaranth at Burndown. Macon Co., GA 2008.* 100 94 a 80 87 b 70 b 60 58 b 40 20 0 c 0 Roundup Firestorm Firestorm + Firestorm + Firestorm + 2 pt 2,4-D (1.5 pt) Clarity (8 oz) Diuron (1.8 pt) *COC included with all Firestorm treatments

Palmer control at planting, burndown applied 17 d earlier. Macon Co., GA 2009. 100 99 a 90 b 80 60 40 20 0 Direx Valor preplant preplant

2 GR Weeds in the Same Field Steckel 2010

Burndown Programs for GR Horseweed/ Palmer Programs: Glyphosate + Clarity (1/ 2 pt)* * + residual herbicide Glyphosate + 2,4-D (2 pt)* * + residual herbicide SE residual: Direx or Valor M S residual: Valor

Preplant/PRE herbicides for Palmer amaranth in Roundup Ready Cotton in SE Preplant PRE Valor Prowl + diuron + Staple Direx Reflex + Staple Reflex + Cotoran Reflex + diuron Reflex + Prowl Prowl + Cotoran Prowl + diuron *Paraquat included with PRE except conventional till!

Palmer amaranth control by PRE herbicides; 40 days* Valor* * Reflex Staple (ALS susceptible) Direx Cotoran Prowl Caparol 0 20 40 60 80 100 % control * Average of 5 locations; 2 in GA, 3 in NC. No other herbicides included. * * Applied same time as the PRE herbicides.

GR Weed Management in Cotton GR Weed Management in Cotton Burndown 30 to 21 DBP Near Planting Pre Emergence Dicamba + Cotoran/Caparol or Reflex glyphosate or apply 14 Reflex on coarse soils Gramoxone DBP and Inteon ½” of rain +/- Valor

Controlling GR Palmer amaranth in RR cotton. 2011. SE and MS. POST1 POST 2 Layby 1-lf cotton 5-6 lf cotton RU + Staple Diuron RU + Dual or Warrant (emerged pigweed) Suprend Layby Pro + RU + Dual or RU + Dual or MSMA Warrant Warrant

Concept of Overlapping Residuals 1 Critical herbicide Herbicide concentration concentration 0.8 0.6 0.4 0.2 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Time

Concept of Overlapping Residuals 1 Critical herbicide Herbicide concentration concentration 0.8 0.6 0.4 0.2 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Time

Concept of Overlapping Residuals 1 Critical herbicide Herbicide concentration concentration 0.8 0.6 0.4 0.2 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Time

Early topical applications with residual needed before Palmer emerges in RR cotton!! POST 1 = 25 days after PRE POST 1 = 17 days after PRE Prowl + Reflex PRE, Roundup + Dual Magnum POST 1, Roundup + Warrant POST 2, Direx + MSMA layby

Hooded Spray or Layby Rig Gramoxone + diuron + COC (+ Valor) Diuron + MSMA + COC (still have to direct to row) Suprend + MSMA + COC Layby Pro + MSMA + COC

Monsanto’s Roundup Ready Cotton Performance Roundup Ready Flex Cotton (Up to $20) Valor 2 oz OR OR Reflex 1 pt = ($4.00) Reflex 1 pt = ($4.00) Valor 2 oz Cotoran, Cotton Pro, Caparol, diuron 2 pt = ($3.00)* Warrant 3 pt or Dual Magnum 1 pt = ($4.50 or $3.00) Gramoxone Inteon Inteon 2 pt = ($1.00) 2 pt = ($1.00) Gramoxone *Will pay on 2 applications

Dryland Conservation Tillage Prowl + Reflex PRE Prowl + Reflex PRE Roundup + Dual POST Ignite + Dual POST Diuron + MSMA PD Diuron + MSMA PD

Palmer response to Ignite WATER VOLUME AND NOZZLE TYPE IS CRITICAL MUST KILL IT WITH THE FIRST APPLICATION

Weed Management in Glufosinate-Tolerant Cotton • Timing is critical!! 3 to 4 inches for consistent Palmer control. This is not a 4-inch pigweed!

32 oz/A Gly 4 fb 29 oz/A Ignite on 12” Palmer

Palmer amaranth must be small (3 to 4 inches) if consistently controlled by Ignite 7 days after IGN application 20 days after IGN application Whitaker

Controlling GR Palmer amaranth in LL conventional DRYLAND cotton. PREPLANT and POST1 POST 2 Layby PRE 1-lf cotton 6-7 lf cotton 1. diuron + Reflex 2. Cotoran + Reflex 3. Prowl + Reflex Ignite 29 oz + diuron Ignite 29 oz Dual Mag. 4. Diuron + Staple + 5. Cotoran + Staple MSMA 6. Diuron PRE 7. Cotoran PRE 8. Treflan PPI

Phytogen Widestrike Cotton 1. Confers tolerance to Ignite 2. Tolerance not complete; injury will occur and yield loss can occur if you don’t know what you are doing. 3. According to EPA, Ignite can be applied to widestrike cotton. 4. However, grower is liable as neither Bayer, Dow, nor any University recommends or warrant the use of Ignite on Widestrike cotton

Phytogen Widestrike Cotton (treated with Ignite) 2004: 1 plot (researchers playing) 2005: 0.25 acres (research) 2006: 16 acres (research) 2007: <20,000 acres 2008: ~40,000 acres 2009: ~225,000 acres 2010: >750,000 acres

Weed management in LL vs WRF cotton LL WRF Agronomic performance Improving Proven Grass control May need help Can apply Roundup Morningglory control Excellent Excellent with Ignite GR horseweed control Good Good with Ignite Can apply Roundup NO! Yes Acceptable (when follow Tolerance to Ignite Excellent recommendations)

375 WideStrike Cotton Tolerance to Multiple Applications of Ignite b a a a Pounds Lint Cotton Culpepper, York and Steckel 2010

375 WideStrike Cotton Tolerance to Multiple Applications of Ignite Num ber of 29 oz/A Ignite Applications Ignite 2 lf, 7 lf, bloom b 1224 Ignite 2 lf and 7 lf a 1444 No Ignite 1417 a 0 200 400 600 800 1000 1200 1400 1600 Pounds Lint Cotton

375 WideStrike Cotton Tolerance to Multiple Applications of Ignite Num ber of 29 oz/A Ignite Applications Ignite 2 lf, 7 lf, bloom b 1224 Ignite 2 lf and 7 lf a 1444 No Ignite 1417 a 0 200 400 600 800 1000 1200 1400 1600 Pounds Lint Cotton

Photo 5 d after 2 lf 2 lf application

Photo 5 d after bloom + 2 wk application

Can not survive with herbicides alone any longer

What percent Palmer amaranth control? Staple + Reflex + Direx PRE Roundup WMax + Parrlay POST Direx + MSMA Layby

Developing Integrated Programs

Hand Weeding Hand Weeding York 2010 2010: GA: Herbicide input: $90 million 2010: TN: Herbicide input: $35 million

Hand Weeding Hand Weeding York 2010 GA: 92% of growers handweeding 53% of the 2010 crop = $16 million TN: growers handweeding 20% of crop = $3 million

TREFLAN/PROWL PRE PPI

Impact of GR Palmer amaranth in Georgia counties with severe infestations.* Before (2004) After (2008) 100 80 % acres 60 40 20 5 0 0 Herbicide Incorp. *Average of Macon, Taylor, Sumpter, Schley, and Dooly counties

Tillage in Cotton During 2010 %PPI # tillage GA Counties 0 0 1-9 Worth, Pualski, Tift, Berrien, Echols, Turner, Brooks, Pierce, 10 M arion, Grady, 10-19 Emanual, M ontgomery, Atkins, Coffee, Lowndes, Dooly, Wilcox, 11 Thomas, Crisp, Schley, Webster, Colquitt 20-29 Bullock, J efferson, Treutlen, Wheeler, Daugherty 5 30-50 Effingham, Telfair, Tattnall, Dodge, Toombs, J eff Davis, Bleckly, 13 Early, Lanier, Irwin, Lee, M acon >50 J enkins, J ohnson, Washington, Screven, Wayne, Laurens, Randolf, 12 Decatur, Seminole, M iller, Taylor Ben Hill

Most Palmer amaranth emerges from top inch

Number of Palmer Amaranth Plants During Early Season. Macon Co., Georgia 2008.* No Deep Tillage Deep Turn No Herbicide Treatment

GR Palmer amaranth control by tillage and cover crop residue. 2006-2010..* 100 80 60 % 40 50 a 20 0 b 0 Deep Weeds inversion *No herbicide

Palmer requires a significant amount of sunlight to emerge!!

>90% control in middles

In the rye, control loss was in the strip

Tons of Issues/Challenges • Activating our residual herbicides! • Palmer free at planting! • Ignite resistance management! • PPO resistance management! • ALS (and other) chemistry resistant mgmt!

Comments or Questions? 2002: $20/A 2010: $63/A