Tolerance of New Peanut Varieties to Old Herbicides

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Tolerance of New Peanut Varieties to Old
Herbicides

• E. P. Prostko and T.L. Grey
• Department of Crop Soil Sciences
• The University of Georgia

APRES - 2007
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What did we use to plant in Georgia???

• 1985
• 47 Florunner
• 32 GK-7
• 9 Southern Runner
• 1995
• 25 Florunner
• 39 GK-7
• 21 Georgia Runner
• 2003
• 88 Georgia Green
• 6 C-99R
• 1 Georgia-O2C

Source UGA Extension Agent Surveys
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The Future of Peanut Varieties???

• AP-3
• Georgia-02C
• C-99R
• Georgia-03L
• York
• McCloud
• Florida-07
• Georgia-06G
• Georgia Greener
• Others???

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The Problem

• Herbicides developed for use in peanut prior to
  1996 have not been adequately tested on new
  varieties.
• Peanut breeding programs are very active and new
  varieties are being released every year.
• Can we assume that the herbicide tolerance of new
  peanut varieties is the same as those previously
  tested?
• Testing all varieties and all herbicides is
  probably impossible.

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Materials and Methods

• Twin rows
• Small plot techniques
• backpack sprayer
• 15 GPA
• flat-fan nozzle tips
• 4 replications
• ANOVA (P 10)
• Weed-free all year
• DNA Strongarm Valor
• Hand-weeding
• Paraquat
• Gramoxone Inteon/Firestorm/ Parazone
• Chlorimuron (Classic)
• Yield/TSWV

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Gramoxone/Firestorm/Parazone (paraquat)
Gramoxone Inteon _at_ 8 ozs/A 80/20 _at_ 0.25 v/v 7 DAC
Gramoxone Inteon _at_ 12 ozs/A Pledge _at_ 8
ozs/A 80/20 _at_ 0.25 v/v 7 DAC
1 DAT
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Peanut Variety Response to Gramoxone Max _at_ 5.5
ozs/A (0.129 lb ai/A) - 2003




LSD 0.10 382
Included NIS _at_ 0.25 v/v
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Peanut Response to Gramoxone Max _at_ 5.5 ozs/A
(0.129 lb ai/A) - 2004.

LSD 0.10 238
Averaged over 3 varieties (GA Green, C99-R, DP-1)
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Gramoxone Inteon (GI) and Basagran (B) Effects on
Peanut Yield of GA-02C (2006)
Averaged over 4 timings (7, 14, 22, 28
DAC) Included 80/20 _at_ 0.25 v/v Weed-free
P 0.63
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Gramoxone Inteon (GI) and Basagran (B) Effects on
TSWV of GA-02C (2006) - 131 DAP
Averaged over 4 timings (7, 14, 22, 28
DAC) Included 80/20 _at_ 0.25 v/v Weed-free
P 0.26
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Gramoxone Inteon (GI) and Basagran (B) Effects on
Pod Color of GA-02C (2006) at Harvest
Averaged over 4 timings (7, 14, 22, 28
DAC) Included 80/20 _at_ 0.25 v/v Weed-free
LSD 0.10 2 (orange) LSD 0.10 3 (yellow)
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Classic (chlorimuron) _at_ 0.5 ozs/A Applied 62 DAE
GA-02C
AP-3
7 DAT
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Classic Effects on TSWV in AP-3(2005) - 128 DAP
Classic _at_ 0.5 ozs/A Activator 90 _at_ 0.25
v/v Weed-free
P 0.55
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Classic Effects on TSWV in AP-3 (2006) - 131 DAP
P 0.11
Classic _at_ 0.5 oz/A 80/20 _at_ 0.25 v/v Weed-free
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Classic Effects on Peanut Yield (AP-3) 2005
Classic _at_ 0.5 ozs/A Activator 90 _at_ 0.25
v/v Weed-free
P 0.59
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Classic Effects on Peanut Yield (AP-3) 2006
Classic _at_ 0.5 ozs/A 80/20 _at_ 0.25 v/v Weed-free
P 0.66
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Classic Effects on TSWV in GA-02C (2006) - 131
DAP
P 0.21
Classic _at_ 0.5 oz/A 80/20 _at_ 0.25 v/v Weed-free
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Classic Effects on Peanut Yield (GA-02C) - 2006
Classic _at_ 0.5 ozs/A 80/20 _at_ 0.25 v/v Weed-free
P 0.37
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Peanut Yield as Influenced by Classic
Applications (2000-2006)
12 trials conducted in GA weed-free conditions
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Paraquat - Summary

• 2003
• significant variety X timing interaction
• No effect on C-99R
• Significant yield loss in DP-1 at 14 DAC
• Significant yield loss in GA Green with all
  timings
• 2004
• No variety X timing interaction
• significant yield loss occurred at 28 DAC
• 2006
• No effect on GA-02C (TSWV or yield)
• Reduction in orange pods/increase in yellow pods
• Repeat in 2007 (GA-02C, GA-03L)

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Chlorimuron - Summary

• AP-3
• 2 years
• No effect on TSWV or peanut yield
• Georgia-02C
• 1 year
• no effect on TSWV or peanut yield
• repeat in 2007 (GA-02C, GA-03L)

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