Peanut ResponsePeanut Response to Valor Application to Valor Application

TimingsTimings

E. P. Prostko and W. C. Johnson III, (GA)

W. J. Grichar (TX)

D. L. Jordan (NC)

G. A. MacDonald (FL)

Valor in PeanutsValor in Peanuts labeled on April 12, 2001 G-E broadleaf weed

control minimal rotation

restrictions narrow application

window unexpected injury

Peanut Acres Treated with Valor Peanut Acres Treated with Valor and Injury by Region in 2001and Injury by Region in 2001

0

5,000

10,000

15,000

20,000

25,000

30,000

Atlantic Southeast Oklahoma Texas

Acr

es

Acres Treated Acres Injured

Source: Valent U.S.A. Corp.

ObjectiveObjective

To evaluate the effects of the timing of Valor on peanut growth, yield, and maturity.

Material and MethodsMaterial and Methods

5 locations small plot techniques 3-4 replications Valor (3 oz/A) applied 0 to

10 DAP weed-free conditions crop injury, yield, maturity

Materials and MethodsMaterials and MethodsGA1 GA2 FL NC TX

Location Tifton Attapulgus Citra Lewiston Yoakum

Variety GAGreen

C-99R GAGreen

NC 12C GAGreen

Planted May 8 Apr 24 May 1 May 2 May 22

Harvested Sept 26 Oct 2 Sept 19 Oct 9 Oct 22

Materials and MethodsMaterials and Methods applications made after 3 DAP are off label peanuts were cracking or emerged on or

after…… * GA1 - 7 DAP

* GA2 - 10 DAP

* FL - 8 DAP

* NC - 7 DAP

* TX - 7 DAP

RESULTSRESULTSCrop InjuryCrop Injury

Crop Injury Summary- ICrop Injury Summary- IStunting/Leaf BurnStunting/Leaf Burn

GA1 - all timings caused significant crop injury (25-88%)

GA2 - significant crop injury 6, 8, and 10 DAP (13-33%)

FL - no crop injury was observed

Crop Injury Summary - IICrop Injury Summary - IIStunting/Leaf BurnStunting/Leaf Burn

NC - significant crop injury when applied 7 and 10 DAP (9-18%).

TX - significant crop injury when applied 7 and 10 DAP (10-30%).

Valor InjuryValor Injury

RESULTSRESULTSYieldYield

Peanut Yield in Response to ValorPeanut Yield in Response to ValorTifton, GATifton, GA

4673

39604221

36803394

2496

1567

0

1000

2000

3000

4000

5000

Timing

lbs/

A

aabc ab bc

c

d

e

Peanut Yield in Response to ValorPeanut Yield in Response to ValorAttapulgus, GAAttapulgus, GA

4526 4552 44084580

41884459

0

1000

2000

3000

4000

5000

0 DAP 2 DAP 4 DAP 6 DAP 8 DAP 10 DAP

Timing

lbs/

A

P = 0.66

Peanut Yield in Response to ValorPeanut Yield in Response to ValorCitra, FLCitra, FL

68756301

6564 6723 67316476

0

1500

3000

4500

6000

7500

Untreated 0 DAP 2 DAP 4 DAP 6 DAP 8 DAP

Timing

lbs/

A

P = 0.31

Peanut Yield in Response to Valor Peanut Yield in Response to Valor Lewiston, NCLewiston, NC

3704 38034027 3881 3939

42973789

0

1000

2000

3000

4000

5000

Timing

lbs/

A

P = 0.56

Peanut Yield in Response to Valor Peanut Yield in Response to Valor

Yoakum, TXYoakum, TX

3394

41204483

4109 39643616

3234

0

1000

2000

3000

4000

5000

Valor Timing

lbs/

A

P = 0.48

RESULTSRESULTSMaturityMaturity

Peanut Maturity in Response to ValorPeanut Maturity in Response to ValorBlack HullsBlack Hulls

33

2319 17

20 19

90

10

20

30

40

50

Valor Timing

%

Tifton, GASeptember 19, 2001

GA GreenPlanted: May 8

a

bb b

b bc

Peanut Maturity in Response to ValorPeanut Maturity in Response to ValorBlack + Brown HullsBlack + Brown Hulls

7866

53 53 54 59

44

0

20

40

60

80

100

Valor Timing

%

Tifton, GASeptember 19, 2001

GA GreenPlanted: May 8

aab

bc bc bc bc

Peanut Maturity in Response to ValorPeanut Maturity in Response to ValorOrange + Yellow HullsOrange + Yellow Hulls

23

34

47 47 4641

56

0

10

20

30

40

50

60

Valor Timing

%

Tifton, GASeptember 19, 2001

GA GreenPlanted: May 8

cbc

ab ab abb

a

Summary - ISummary - I

Valor caused significant crop injury, particularly when applied at 6 DAP or later.

Peanuts yields were not reduced by any application of Valor in 4 out of 5 tests.

Summary - IISummary - II

In Tifton, GA, Valor caused significant yield reductions when applied 3 DAP or later.

In Tifton, GA peanut maturity was delayed (7-14 days) as indicated by differences in hull color at harvest.

Valor in Peanuts - 2002Valor in Peanuts - 2002SuggestionsSuggestions

calibration pre-slurry plant 1.5” deep apply at planting do not irrigate when

cracking hull scrape limited acreage

University ofGeorgia

ExtensionWeed Science

(gaweed.com)