1 / 43

Living and Learning with Herbicide Resistant Weeds

Living and Learning with Herbicide Resistant Weeds. Eric P. Prostko and A. Stanley Culpepper Extension Weed Specialists Department of Crop & Soil Sciences. UGA Faculty Tim Grey (Tifton) Bill Vencill (Athens) Mark Czarnota (Griffin) Tim Murphy (Griffin) USDA-ARS Carroll Johnson

sela
Download Presentation

Living and Learning with Herbicide Resistant Weeds

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Living and Learning withHerbicide Resistant Weeds Eric P. Prostko and A. Stanley Culpepper Extension Weed Specialists Department of Crop & Soil Sciences

  2. UGA Faculty Tim Grey (Tifton) Bill Vencill (Athens) Mark Czarnota (Griffin) Tim Murphy (Griffin) USDA-ARS Carroll Johnson Ted Webster Post-Doc’s Lynn Sosnoskie Valdosta State Univ. Richard Carter Technical Support Charlie Hilton Amy Davis Jesse Parker Kevin Baldree Administrative Dena Watson Graduate Students Rebekah Wallace Trey Cutts Student Workers Too many to mention but Very valuable to program UGA Weed Science TeamSupporting Cast & Crew

  3. Palmer Amaranth in Georgia

  4. Do what must be done?

  5. SWSS Weed ID Guide Why Palmer Amaranth (Amaranthus palmeri)? • 38 species of Amaranthus in U.S. • 27 species found in SE • dioacious • grows faster than other pigweeds (1-2” per day!!) • more competitive than other pigweeds • prolific seed producer • seed to seed 9-12 WAE • 2 generations/year • herbicide tolerance

  6. Herbicide Resistance Concerns in Georgia • glyphosate • ALS herbicides • Atrazine • Multiple resistance • Glyphosate + ALS

  7. Georgia counties confirmed to be infested with glyphosate-resistant Palmer amaranth. 2004 – 1 county 2005 – 2 counties 2006 – 7 counties 2007 – 10 counties 2008 – 6 so far 1-28-09

  8. GA Confirmed ALS-Resistant Palmer Sites

  9. 2008 Triazine Resistance SurveyMacon County 4/20 sites resistant to 10X rate (4,5,15,20) 6/20 sites took 5 qts/A to kill (3,6,8,14,17,19)

  10. Site 5 – Atrazine Resistance Survey 0 0.1 1 5 10 Atrazine (qts/A) *Not resistant to Evik (ametryn) or Direx (diuron)

  11. How did this happen to us????? • Economics drive farmer decisions • No real long-term weed mgt. planning • Farm logistics • Overuse of glyphosate • Overuse of Staple and Cadre • Reduced herbicides rates • Reduced tillage • Reduction in use of residuals • Dryland production systems

  12. Palmer Amaranth Biology • How many seed? • How long can the seed survive in the soil? • Where does most of the germination occur? • Pollen Drift

  13. Palmer amaranth seed production in Georgia from a single female plant when competing with cotton for the season 450,000 Macon Co. 2006 # of seeds *1,000,000 seed/plant (Keeley et al. 1987. Weed Science 35:199-204) California

  14. R-Palmer amaranth seed longevity Source: Dr. Lynn Sosnoskie - UGA

  15. Influence of burial depth on Palmer amaranth emergence in Georgia Source: Dr. Lynn Sosnoskie - UGA

  16. Herbicide Resistant WeedsPollen Drift • Off-site movement (wind, gravity, insects, man, animal) of resistance trait through pollen • Pollen from resistant male fertilizes susceptible female to produce resistant progeny (seed) • UGA researchers have documented GR-trait movement of at least 960’ (Palmer amaranth). Palmer Amaranth Pollen Source: Dr. Lynn Sosnoskie

  17. In-field Palmer amaranth pollen movement

  18. Cultural Practices • Deep tillage • Extreme cover crops

  19. No Deep Tillage Deep Turn No Herbicide Treatment

  20. Palmer amaranth seedling density as influenced by tillage.

  21. Dryland Systems

  22. Irrigation in Georgia Source: Kerry Harrison, UGA Extension Engineer

  23. May-June 2008 Rainfall Distribution in Midville Crops planted from May 21-June 21 did not receive enough rainfall to activate herbicides (0.26” total). June Rainfall = 0.62” which occurred as follows:12 (0.08”); 22 (0.36”); 26 (0.08”); 29 (0.10”)

  24. If residual herbicides are not activated on a timely basis with a reliable water source, pigweed control will be very difficult, maybe even impossible!

  25. Dryland Systems • Growers need to think about mechanical herbicide incorporation • Will help but not a guarantee • Success will depend upon…… • operator • Implement • Soil conditions

  26. Chemical Control Options • Valor (flumioxazin) • Reflex (fomesafen) • Dual Magnum (S-metolachlor) • Atrazine • Liberty-Link (glufosinate) • Sencor products (metribuzin) • KIH-485

  27. Palmer Amaranth Control in PeanutsMacon County, GA – 2007 (38 DAT) NTC Valor SX 51WG @ 3 oz/A

  28. Palmer Amaranth Control in PeanutsMacon County, GA – 2007 (38 DAT) Dual Magnum 7.62EC @ 1 pt/A NTC

  29. Macon County – GR Palmer Amaranth June 24, 2008 – 60 DAP CN-01-08 Atrazine 4L @ 1 qt/A – PRE Atrazine 4L @ 1.5 qt/A – 30 DAP Peptoil @ 1% v/v – 30 DAP NTC

  30. RR vs LL Corn - 2008 Roundup W-Max @ 22 oz/A Atrazine @ 1.5 qt/A Prowl H2O @ 2.1 pt/A (POST) Ignite 2.34 SL @ 23 oz/A Atrazine @ 1.5 qt/A Prowl H2O @ 2.1 pt/A AMS @ 3 lb/A (POST) Untreated CN-11-08 6/17/2008 81 DAP

  31. Metribuzin Products on Soybeans • Sencor • Boundary • Dual Magnum + Sencor • Canopy • Sencor + Classic • Read label • Know soil texture and OM • Varieties • rotations

  32. GR-Pigweed Control in Soybeans - 2008 NTC Canopy 75DG @ 6 oz/A + Prowl H2O 3.8ASC @ 2.1 pt/A (PRE) SB-06-08 Macon County 48 DAP

  33. GR-Palmer Amaranth Control in Soybeans - 2007 Gramoxone Inteon @ 3 pt/A + Boundary @ 1.8 pt/A + NIS @ 0.25% v/v (7 DBP) Touchdown Total @ 1.5 pt/A (26 DAP) NTC SB-01-07 Macon Co. 76 DAP

  34. Soybean varieties screened in 2008 that had adequate tolerance to Boundary 6.5EC (2 pt/A), Canopy 75DG (5 oz/A), and Sencor 75DG (6 oz/A). • Ag South AGS 568 Asgrow H7242 • Asgrow 4903 RR/STS Delta Pineland DP 5634 • Delta Pineland DP 6568 Northrup King NKS 80P2 • Northrup King NKS 76L9 Northrup King NKS 78G6 • Pioneer 95Y40 Pioneer 95Y70 • Pioneer 96M60 Pioneer 97M50 • Southern States RT5951 Southern States RT4808 • Vigoro V61N9 Vigoro V74N9

  35. GR-Pigweed Control in Soybeans – 2008 Macon County 90% Valor @ 3 oz/A; Envive @ 3 oz/A; Reflex @ 1 pt/A; Prefix @ 2 pt/A; Canopy @ 6 oz/A; Sencor @ 8 oz/A KIH-485 @ 4.2 oz/A; Dual Magnum @ 1 pt/A

  36. KIH-485 • Pyroxasulfone • Kumiai • Developed for corn and soybeans • PRE • Herbicide Family • Sulfonylioxazoline (?) • Herbicide Mode of Action (?) • plant growth inhibitor that affects apical meristem and coleoptile development of plants after seed germination • Low use rates

  37. GR-Palmer Amaranth Control in Soybeans with PRE’s (2008) - Macon Co. KIH-485 85WG @ 4.2 oz/A NTC SB-05-08 48 DAT

  38. Under Utilized Modes of Action • HPPD-inhibitors • Mesiotrione (Callisto) • Tembotrione (Laudis) • Topramezone (Impact)

  39. Halex GT in Field Corn - 2008 Halex GT 4.39L 4 pt/A + NIS (POST) Untreated CN-05-08 6/19/2008 83 DAP

  40. Don’t forget!!! There are no steel resistant weeds!!!

  41. We are overusing the PPO inhibiting herbicides!!!!!!!! • Resistance has already been reported in other areas!!! • Common waterhemp • 2001 (Kansas) • 2002 (Illinois) • 2003 (Missouri) • Common ragweed • 2005 (Delaware) • Wild poinsettia • 2004 (Brazil)

  42. For More Weed Science Info:www.gaweed.com eprostko@uga.edu 229-386-3328 (office) 229-392-1034 (cell)

More Related