Cotton Production Workshop

A. Stanley Culpepper

Breakout Session Objectives1. New labels or uses

2. RR cotton tolerance to glyphosate

3. Managing weeds that are difficult to control in RR cotton

4. Glyphosate/tank mixes

5. Replacing Bladex

6. Cadre carryover

7. DNA application timing in strip-till

8. Layby applications in liquid N

New Labels or Uses 1. Paraquat formulations:

Boa (2.5 lb ai) Gramoxone Extra (2.5 lb ai)Gramoxone Max (3.0 lb ai)

2. Glyphosate formulations:

Glyphosate Formulations* Acquire

Credit

DuPont Glyphosate

Gly-Flo

Glyfos

Glyfos X-TRA

Glyphomax

Glyphomax Plus

Glyphosate Original

Rattler

Roundup D-Pak

Roundup Original

Roundup Ultra

Roundup UltraDry

Roundup UltraMax

Touchdown

*Products in orange may be applied overtop of RR cotton according to label.

Roundup Ready Cotton Tolerance to Roundup, Touchdown, and Touchdown 5. Clayton, NC. 2000.*

Roundup Ultra 0 0

Touchdown 0 0

Touchdown 5 39 63

% injury

1 application 2 applications

*Glyphosate applied at 1 lb ai/A. ACY

Roundup Ultra 84

Roundup + Harvade 92

Roundup + Harvade + COC 99

Harvade + MSMA + COC 99

Smallflower

morningglory

Morningglory Control in RR Cotton by Harvade Mixtures. Attapulgus, GA. 2000.*

*Roundup Ultra 2 pt/A; Harvade 6 oz/A when mixed with RU and 10 oz/A when mixed with MSMA; MSMA 2.67 pt/A

Breakout Session Objectives1. New labels or uses

2. RR cotton tolerance to glyphosate

0

10

20

30

40

50

60

70

RR Cotton Stacked Cotton RR-Tolerant

Transgenic Cotton Acreage in Georgia

32 32

64%

400

600

800

1000

1200

No RU 3 lf 3,6 lf 3,6,9 lf

Lint Cotton Yields in RR Cotton when Treated Topically with Glyphosate at Various Growth Stages

1) Ten plants per plot were hand harvested on October 10, 1999 in Moultrie, GA.

2) Roundup Ultra applied at 1 qt/A broadcast over-the-top. Conventional plots treated with standard herbicide system.

a a a

b

Glyphosate Overtop After 4th Leaf Stage

Can cause boll shed, delay maturity

Salvage treatment only

Is Stem Absorption of Glyphosate Directed in RR Cotton a Concern?

No noted concerns with precision applications in field trials

Lab data from North Carolina, Georgia, and Mississippi?

What about sloppy directed applications?

0

150

300

450

600

750

900

Cotton Yield After Various Glyphosate Applications. Moultrie, 2000.*

*Glyphosate applied at 1.0 lb ai/A. PD = precision directed at cotyledons; SD = sloppy directed 33 to 40% up the plant. Standard system = Prowl + Cotoran fb Staple fb Caparol + MSMA.

LSD = 55

Lin

t yie

ld (

Lb/

A)

Standard system

Topical 1- & 4-lf

Topical 4-lf PD 8- & 12-lf

Topical 4-lf SD 8- & 12-lf

a a a

bb

Topical 1-, 4-, & 12-lf

Directing Glyphosate in RR Cotton?

Precision PD or hooded sprayers

Directing Glyphosate in RR Cotton?

Precision PD or hooded sprayers

Direct spray to the base of the cotton plants

Directing Glyphosate in RR Cotton?

Precision PD or hooded sprayers

Direct spray to the base of the cotton plants

Contact of spray with cotton leaves should be avoided to the maximum extent possible

Directing Glyphosate in RR Cotton?

Precision PD or hooded sprayers

Direct spray to the base of the cotton plants

Contact of spray with cotton leaves should be avoided to the maximum extent possible

Place nozzles in low position directing a horizontal spray pattern under the cotton leaves to contact weeds in the row

Precision and Sloppy Applied Glyphosate

Precision and Sloppy Applied Glyphosate

Breakout Session Objectives1. New labels or uses

2. RR cotton tolerance to glyphosate

3. Managing weeds that are difficult to control in RR cotton

Weeds Difficult to Control by Glyphosate?

Cutleaf Eveningprimrose Response to Burndown Herbicides

Treatment Rating

Gramoxone F

Gramoxone + Direx G

Glyphosate F

Glyphosate + Direx G

Glyphosate + Harmony Extra F-G

Glyphosate + Clarity G

Glyphosate + 2,4-D E

20

40

60

80

100

2 inch5 inch8 inch

% c

ontr

olCutleaf Eveningprimrose Control by Glyphosate and 2,4-D. Tifton, 2000.*

*Roundup Ultra applied at 1 qt/A. Ratings 24 days after treatment.

glyphosate 2,4-D

0

2.5

5

7.5

10

Glyphosate 2,4-D

2 inch5 inch8 inch

Gra

ms/

plot

Cutleaf Eveningprimrose Fresh Weights After Treating with Burndown Herbicides. Tifton, 2000.*

*Fresh weights taken from 12 plants per plot. Roundup Ultra applied at 2 pt/A and 2,4-D at 1 pt/A.

2,4-D Burndown for Cotton(from fallow land section of labels)

No specific language concerning cotton

Do not plant any crop in treated fallow land until 3 months after treatment or until chemical has disappeared from soil

Current Recommendations -- 2,4-D Burndown for Cotton

1 pt/acre Alone or mixed with glyphosate Applied 45 days before planting Research to date shows effectiveness

and crop safety

Cotton Injury from 2.1 mls Per Acre of 2,4-D. Tifton, 2000.

Weeds Difficult to Control by Glyphosate?

USE A DNA HERBICIDE

Florida Pusley Control with Glyphosate and Glyphosate Tank Mixtures. Tifton, 2000.*

0

20

40

60

80

100

Glyphosate + 2,4-D + Direx + Caparol

% c

ontr

ol

87

bc

92

ab

99

a 81

bc

*Florida pusley 2 inches. Roundup UltraMAX applied at 1.25 pt; 2,4-D at 1 pt; Direx or Caparol at 1.5 pt.

Weeds Difficult to Control by Glyphosate?

Controlling Yellow and Purple Nutsedge?

Nutsedge Control Programs: 1) 2 applications of glyphosate prior to 5th leaf followed by conventional chemistry including 2 lb ai MSMA directed

2) 1 application of glyphosate prior to 5th leaf followed by conventional chemistry including 2 lb ai MSMA directed

3) 2 applications of glyphosate

4) Zorial or Staple?????

Yellow and Purple Nutsedge Control by Glyphosate. Greenhouse.

0

25

50

75

100

0.25 0.5 0.75 1

yellow purple

Glyphosate (lb)

*Purple nutsedge controlled significantly greater than yellow nutsedge.

42 42

81 7790

82

% c

ontr

ol

**

70

98

*

LSD=10

Yellow and Purple Nutsedge Control by MSMA. Greenhouse.

0

25

50

75

100

0.5 1 2

yellow purple

MSMA (lb)

*Yellow nutsedge controlled significantly greater than purple nutsedge.

48 42

6149

8269

% c

ontr

ol

**

LSD=10

Weeds Difficult to Control by Glyphosate?

Mid-Season Morningglory Control by Glyphosate & Glyphosate/Staple Mixtures. Moultrie, 2000.

Things to consider?1. Morningglory size at time of application (5 inches here).2. Will you post-direct with conventional chemistry or glyphosate?

Glyphosate 73 89

Glyphosate + Staple 93 97

Pitted Smallflower

morningglory morningglory

Glyphosate/Staple Tank Mixtures

DuPont label allows tank mix of 1.5 pt of Roundup Ultra plus 0.6 oz of Staple per acre broadcast

DuPont’s Staple Plus

50

60

70

80

90

100

Roundup + Bladex + Caparol + Direx + Valor

Smallflower Morningglory Control by Glyphosate Alone and Mixed with Residual Herbicides; Attapulgus, 2000.

% control

Smallflower mg 4 to 5 inches; irrigated environment

Roundup (2 pt/A), Bladex (1.5 pt/A), Caparol (1.5 pt/A), Direx (1.5 pt/A), Valor (2 oz/A)

a

ba a a

Weeds Difficult to Control by Glyphosate?

Asiatic Dayflower Control by Glyphosate & Glyphosate/Staple Mixtures. Grady Co., 2000.*

0

20

40

60

80

100

% c

ontr

ol

*Dayflower 1 to 5 inches. Ratings 30 days after treatment. Roundup Ultra applied at 1.5 pt/A and Staple at 0.6 oz/A.

67

90

Glyphosate Glyphosate + Staple

Asiatic Dayflower Control by Glyphosate Mixtures at Layby. Grady Co., 2000.*

0

20

40

60

80

100

Glyphosate +Caparol + Cobra +Direx +Harvade +Valor

% c

ontr

ol

LSD = 10

*Dayflower 1 to 5 inches. Ratings taken 30 days after directing in 8 to 10 inch cotton. Roundup Ultra, Caparol, and Direx applied at 1.5 pt/A. Cobra, Harvade, and Valor applied at 8 oz/A, 8 oz/A, and 2 oz/A, respectively.

6780

86 81 7685

Asiatic Dayflower Control by Conventional Layby Herbicides. Grady Co., 2000.*

0

20

40

60

80

100

MSMA +Bladex +Caparol + Cobra +Cotoran +Direx +Harvade +Linex +Valor

% c

ontr

ol 8090 84 82 78 78

90

LSD = 9

91 85

*Dayflower 1 to 5 inches. Ratings taken 30 days after directing in 8 to 10 inch cotton. Bladex, Caparol, Cotoran, and Direx applied at 2 pt/A. Cobra, Harvade, Linex, MSMA, and Valor applied at 9.6 oz/A, 9 oz/A, 1.5 pt/A, 2.67 pt/A, and 2 oz/A, respectively.

Weeds Difficult to Control by Glyphosate?

Hemp Sesbania Control by Glyphosate. Tifton, 2000.*

0

20

40

60

80

100

% c

ontr

ol

*Roundup Ultra applied at 2 pt/A. Experiment conducted under center irrigation.

3 inches 7 inches

86

59

Breakout Session Objectives1. New labels or uses

2. RR cotton tolerance to glyphosate

3. Managing weeds that are difficult to control in RR cotton

4. Glyphosate/tank mixes

Glyphosate + Tank Mix Partner

1. Increase morningglory control

2. Increase dayflower control

3. Residual weed control

Tank Mix Partners-Early Season

1. Staple

RR Cotton Injury from Glyphosate/Staple Mixtures

0

5

10

15

20

Staple Ultra + Staple

Original +Staple

DPXAA46

3 DAT

14 DAT

Cotton Injury from Glyphosate/Staple Combinations. Tifton, 2000.*

*Glyphosate applied at 0.75 lb ai/A. Staple applied at 0.6 oz/A. Cotton 4-leaf at time of application.

LSD = 4

% in

jury

Tank Mix Partners-Early Season

1. Staple*

2. Dual Magnum

*Labeled tank mix with Roundup

Dual PRE

Do Not Use Dual PRE on Georgia Soils

Tank Mix Partners-Early Season

1. Staple*

2. Dual Magnum

3. MSMA

*Labeled tank mix with Roundup

Tank Mix Partners-Late Season

1. Diuron* 6. Harvade*

2. Caparol 7. MSMA

3. Cyanazine* 8. Dual Magnum

4. Cotoran 9. Prowl*

5. Cobra

*Label supports tank mix with Roundup

Tank Mix Partners Consider...

weed species and sizes, economics, cotton stage, environment??

Tank Mix Partners Consider...

weed species and sizes, economics, cotton stage, environment??

DON’T FORGET ABOUT ANTAGONISM

50

60

70

80

90

100

glyphosate + Bladex + Caparol + Direx + Valor

Texas Panicum Control by Glyphosate Alone and in Mixture with Residual Herbicides. Ponder Farm, 1999.

% control

Texas panicum 6 to 9 inches; fair to dry environment

Roundup (2 pt/A), Bladex (1.5 pt/A), Caparol (1.5 pt/A), Direx (1.5 pt/A), Valor (2 oz/A)

a

bab

a

b

50

60

70

80

90

100

glyphosate + Bladex + Caparol + Direx + Valor

Palmer Amaranth Control by Glyphosate Alone and Mixed with Residual Herbicides. Attapulgus, 2000.

% control

Palmer amaranth 4 to 7 inches; irrigated environment

Roundup (2 pt/A), Bladex (1.5 pt/A), Caparol (1.5 pt/A), Direx (1.5 pt/A), Valor (2 oz/A)

aba

bb

ab

Roundup Ultra (1 qt/A) + Caparol (1.5 pt/A)

Glyphosate preferred for grasses and perennials

Otherwise, conventional chemistry preferred

1. Better morningglory and dayflower control

2. Residual weed control

3. Resistant management strategy

4. Avoid weed shifts

5. Reduce risk of boll shed

Should I Direct Glyphosate in RR Cotton?

Breakout Session Objectives1. New labels or uses

2. RR cotton tolerance to glyphosate

3. Managing weeds that are difficult to control in RR cotton

4. Glyphosate/tank mixes

5. Replacing Bladex

Manufacturing ceased in 1999

Availability in 2001: 0, 40, 50?????

Bladex label:

May not be sold or distributed after Sept. 30, 2002.

May not be used after December 31, 2002.

Do not apply more than 1.0 qt/A (1.0 lb ai/A).

An enclosed cab is required.

Cyanazine Availability

Controls most troublesome broadleaf weeds when mixed with MSMA

Cotton tolerance acceptable if applied timely and precisely

Residual weed control for several weeks

Cyanazine (Bladex, Cy-Pro)

Other mid-season post-directed herbicide options: 1) Dual

2) Prowl

3) MSMA or DSMA

4) Cobra

5) Harvade

6) Goal

7) fluometuron (Cotoran, Meturon)

8) prometryn (Caparol, Cotton-Pro)

9) diuron (Karmex, Direx)

Replace Cyanazine?

Smallflower Morningglory Control by Conventional Layby Herbicides. Turner Co., 2000.*

0

20

40

60

80

100

MSMA +Bladex +Caparol + Cobra +Cotoran +Direx +Harvade +Linex +Valor

% c

ontr

ol

64

8190

64

97 99

78

LSD = 13

9176

*Morningglory 6 to 8 inches. Ratings taken 30 days after directing in 8 to 10 inch cotton. Bladex, Caparol, Cotoran, and Direx applied at 2 pt/A. Cobra, Harvade, Linex, MSMA, and Valor applied at 9.6 oz/A, 9 oz/A, 1.5 pt/A, 2.67 pt/A, and 2 oz/A, respectively.

Tropic Croton Control by Conventional Layby Herbicides. Turner Co., 2000.*

0

20

40

60

80

100

MSMA +Bladex +Caparol + Cobra +Cotoran +Direx +Harvade +Linex +Valor

% c

ontr

ol

*Croton 2 to 6 inches. Ratings taken 30 days after directing in 8 to 10 inch cotton. Bladex, Caparol, Cotoran, and Direx applied at 2 pt/A. Cobra, Harvade, Linex, MSMA, and Valor applied at 9.6 oz/A, 9 oz/A, 1.5 pt/A, 2.67 pt/A, and 2 oz/A, respectively.

60

8397

55

92 99

67

LSD = 12

91

61

0

20

40

60

80

100

3 inch 6 inch 9 inch

Caparol

Direx

% c

ontr

olSicklepod Control Comparison of Caparol

and Direx. Tifton, 2000.*

*All treatments included MSMA at 2 lb ai/A and 0.25% v/v NIS.

0

20

40

60

80

100

3 inch 6 inch 9 inch

Caparol

Direx

% c

ontr

olSmallflower Morningglory Control Comparison

of Caparol and Direx. Tifton, 2000.*

*All treatments included MSMA at 2 lb ai/A and 0.25% v/v NIS.

0

20

40

60

80

100

3 inch 6 inch 9 inch

Caparol

Direx

% c

ontr

olPalmer Amaranth Control Comparison of

Caparol and Direx. Tifton, 2000.*

*All treatments included MSMA at 2 lb ai/A and 0.25% v/v NIS.

0

20

40

60

80

100

3 inch 6 inch 9 inch

Caparol

Direx

% c

ontr

olHemp Sesbania Control Comparison of Caparol

and Direx. Tifton, 2000.*

*All treatments included MSMA at 2 lb ai/A and 0.25% v/v NIS.

Other mid-season post-directed herbicide options:

prometryn (Caparol, Cotton-Pro)

diuron (Karmex, Direx)

Weed control - most weeds? Residual weed control - most weeds? Carryover?

experiments being conducted

Replace Cyanazine?

Breakout Session Objectives1. New labels or uses

2. RR cotton tolerance to glyphosate

3. Managing weeds that are difficult to control in RR cotton

4. Glyphosate/tank mixes

5. Replacing Bladex

6. Cadre carryover

Cadre carryover Non-treated

Cadre Carryover

11 cultivars compared for tolerance including Delta Pearl, DP 33 B, DP 5415, DP 458, ST 4892, STX 9903, BXN 47, FM 989, AP 6101, GA 161, SG 125.

1) no difference in plant stand

2) visual injury similar among cultivars

3) vigor reductions similar among cultivars

4) plant height reductions similar among cultivars

Breakout Session Objectives1. New labels or uses

2. RR cotton tolerance to glyphosate

3. Managing weeds that are difficult to control in RR cotton

4. Glyphosate/tank mixes

5. Replacing Bladex

6. Cadre carryover

7. DNA application timing in strip-till

0

20

40

60

80

100

Large Crabgrass Control by Various Application

Methods of Prowl. Rocky Mount, NC. 2000.*

% control

14 b

66 a

ACYEarly pre-plant

Before strip-tillage

79 a

After planting

*Roundup applied early pre-plant and at planting. Ratings taken 16 days after planting. EPP applied 21 d prior to planting.

0

20

40

60

80

100

Slender Amaranth Control by Various Application

Methods of Prowl. Clayton, NC. 2000.*

% control

40 c

66 b

*Roundup applied early pre-plant and at planting. Ratings taken 28 days after planting. EPP applied 21 d prior to planting.

ACYEarly pre-plant

After planting

97 a

Before strip-tillage

Breakout Session Objectives1. New labels or uses

2. RR cotton tolerance to glyphosate

3. Managing weeds that are difficult to control in RR cotton

4. Glyphosate/tank mixes

5. Replacing Bladex

6. Cadre carryover

7. DNA application timing in strip-till

8. Layby applications in liquid N

0

10

20

30

40

50

Caparol Direx Harvade +COC

Cobra Valor

- N

+ N

Cotton Injury from Directed Herbicides in Water and Water/N Mixtures. Tifton, 2000.*

*All treatments included MSMA at 2 lb ai/A. N mixtures were half water and half 30% N. Ratings taken 3 wk after treatment. Cotton 8 to 10 inches at time of application.

LSD = 7

% in

jury

Things to Come

1. Valor

2. Liberty Link Cotton

3. CGA 362-622

4. Enhanced Roundup Ready Cotton