Agriculture Forever Stanley Culpepper Tifton, GA - PowerPoint PPT Presentation

2014: Herbicide Resistance Changes Agriculture Forever Stanley Culpepper Tifton, GA

Herbicide-resistance is not a new phenomenon! Its been happening since 1968!

The U.S. Wins the Gold Medal in Herbicide Resistance!!!! Source: International Survey of Herbicide Resistant Weeds (10/4/12)

Confirmed Cases of Herbicide-Resistant Weeds in the United States 11 2 10 13 17 18 13 12 5 10 CT-2 27 2 DE-7 22 7 8 HI- 4 21 22 16 1 4 MD-11 26 9 22 13 4 MA-2 11 20 6 NH-2 24 2 5 NJ-4 11 19 5 RI-1 8 6 VT-2 5 Source: International Survey of Herbicide Resistant Weeds (10/4/12)

Resistance Development Economics, Effectiveness, and Ease of the herbicide(s) AND Biology of the weed

Roundup Very Economical Ready Very Effective Technology Extremely Easy

Resistance Development Economics, Effectiveness, and Ease are almost always the main factors 1. Single mode of action applied to large acreage 2. Few or no alternative classes of chemistry used 3. Little to no tillage 4. Little to no rotation in crops 5. Often in stressful environments when herbicide activity is minimized 6. Reduced herbicide rates, poor coverage, etc.. that minimize activity

Tremendous Selection Pressure

Selection Pressure Overuse of herbicide chemistry Resistance Herbicide Resistance: The acquired (inherited) ability of a weed population to survive a herbicide application that previously was known to control the population.

Palmer amaranth Changes Agriculture Herbicide Biological Resistance Attributes 2005-2011

What makes Palmer special? 1. Herbicide resistance?

Oh my, how great it was!!!!!!

WeatherMax 176 oz; POST 2”, 5”, and 8” (at least 24 times more lb active than normally needed) cotton

Weathermax 88 oz Staple LX 10 oz

What makes Palmer special? 1. Herbicide resistance? 2. Growth rate?

Picture taken 7 am on 7-9-07 4 inches 52 hr

Picture taken 7 am on 7-9-07 1/2 inch 12 hr (overnight)

What makes Palmer special? 1. Herbicide resistance? 2. Growth rate? 3. Large stature?

Rapid Growth Becoming Extremely Large

What makes Palmer special? 1. Herbicide resistance? 2. Growth rate? 3. Large stature? 4. Competitive ability?

Crop Rotation Yield Loss (%) from 1 AMAPA/row meter

What makes Palmer special? 1. Herbicide resistance? 2. Growth rate? 3. Large stature? 4. Competitive ability? 5. Reducing harvest efficacy?

Impact on Harvest

What makes Palmer a special? 1. Herbicide resistance? 2. Growth rate? 3. Large stature? 4. Competitive ability? 5. Reducing harvest efficacy? 6. Seed production?

Number of Seed Produced per Plant Glyphosate-Resistant Weeds in US 500,000 450,000 450 K 400,000 350,000 300,000 309 K 250,000 200,000 230 K 150,000 100,000 28 K 50,000 250 0 Giant Johnson Horseweed Waterhemp Palmer ragweed -grass amaranth Ragweed = Harrison et al. 2001; johnsongrass = Warwick and Black (1983); horseweed = Regehr and Bazzaz (1979); waterhemp = Nordby and Hartzler (2004); Palmer amaranth = Macrae et al (2009).

Palmer amaranth seed production allows for rapid field domination Year 1 Year 3 to 4

What makes Palmer special? 1. Herbicide resistance? 2. Growth rate? 3. Large stature? 4. Competitive ability? 5. Reducing harvest efficacy? 6. Seed production? 7. Rapid spread?

Role of pollen movement and gene-flow in the spread of herbicide resistance

Pollen-flow can move genes across the landscape

And a trait becomes established in a new population

Traditional Grower Response To Resistance 1. It want happen to me! 2. Ok, its starting to happen to me so when will the next new herbicide be here? (1992 was last new mode of action) 3. O *$&#, I got a mess. It’s on!

Traditional Grower Response To Resistance 1. It want happen to me! 2. Ok, its starting to happen to me so when will the next new herbicide be here? (1992 was last new mode of action) 3. O *$&#, I got a mess. It’s on! The challenge for Extension and Industry is figuring out how to skip steps 1 and 2 moving straight into step 3.

Helping Growers Respond More Quickly 1. Unified communication 2. Unbiased research defining potential impact from resistant weed. 3. Provide management programs that are as simple and economical as possible.

2000-2005: Herbicide costs = $27.80/A 2006-2010: Herbicide costs = $68.00/A Herbicide input increased from 4.25 to 10.625 lb ai/A

Changes in Herbicide Management 2002: $24/A 2010: $63/A Roundup + Valor Burndown1 Roundup Burndown Gramoxone + Reflex + Direx PRE Roundup POST 1 Roundup + Staple POST 1 Roundup POST 2 Roundup + Dual POST 2 Roundup + diuron PD Direx + MSMA PD

2004: 17% of growers hand-weeded 5% cotton acres at $2.40/A Photo by A.C. York 2010 2010: 92% of growers hand-weeded 52% cotton acres at $23.70/A

Tillage is now a common scene 2004: 13.1% of cotton acres cultivated 2010: 32.1% of cotton acres cultivated Herbicide incorporation: 264,266 A (26.7%) Deep turn: 256,075 A last 3 yr

Current Cotton Situation Cost to Manage Palmer in GA Cotton 1. Herbicide input: $68.00 per A $88 million 2. Hand weeding: $11.40 per A $15 million 3. Additional tillage: $5.84 per A $7.6 million 4. Yield loss ??? ???? $110 million

RR Herbicide Program Getting Better* 2010 2012 *Conditions first six wk after planting drier during 2012 than 2010.

Growers Making Good Decisions IS KEY!!!!! 1. Diversified (more than just spray, spray, spray) 2. Timely herbicide applications (residuals key!) 3. Understand Palmer amaranth biology 4. More effective weed management programs

Growers Making Good Decisions IS KEY!!!!! 4. More effective weed management programs A. Herbicides (residuals, tank mixes, etc.) B. Hand weeding C. Selective applicators D. Control before, during, and after crop E. Timeliness is still key F. Overall objective is to eliminate seed production

Relying Too Heavily on Herbicides?? How long will Liberty last? How long will residual of Reflex and Valor last?

2013-2015: Develop better programs reducing selection pressure on ALL herbicides

Using Heavy Rye Covers For Sustainability Rye Cover Weedy Cover

Herbicide Resistance: Will You Survive? 25 plants per 1,089,000 plants = square foot emerge per acre If resistance is one in a billion then you only need 918 acres to find that plant. (historically resistance is 1 plant in population of 1- 10 million…9.18 acres)

Questions/Comments Heavy Rye Production System: www.farmprogress.com/heavycover