control of glyphosate-resistant palmer amaranth in dht cotton
DESCRIPTION
Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton. Culpepper and Chaffin; University of Georgia Braxton and Richburg; Dow AgroSciences. Georgia counties confirmed to be infested with glyphosate-resistant Palmer amaranth. 2004 – 1 county. 2005 – 2 counties. 2006 – 7 counties. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/1.jpg)
Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton.
Culpepper and Chaffin; University of Georgia
Braxton and Richburg; Dow AgroSciences
![Page 2: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/2.jpg)
Georgia counties confirmed to be infested with glyphosate-resistant Palmer amaranth.
2004 – 1 county
2005 – 2 counties
2006 – 7 counties
2007 – 10 counties
2008 – 18 counties
![Page 3: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/3.jpg)
![Page 4: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/4.jpg)
Hand weeding cotton during 2009
52 counties surveyed Acres in survey: 799,000 Acres hand weeded: 437,660 54% cotton hand weeded
$3 to $100/A Average $26 $11.4 million
Grower Costs
Acres Hand Weeded
![Page 5: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/5.jpg)
Some of the hand weeding expense was from the removal of plants from the field.
![Page 6: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/6.jpg)
GR Palmer amaranth control in dryland conservation tillage systems
Prowl + Reflex PRE
Roundup + Dual POST
Diuron + MSMA PD
Prowl + Reflex PRE
Ignite + Dual POST
Diuron + MSMA PD
![Page 7: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/7.jpg)
Palmer Amaranth regrowth after being treated with Ignite.
![Page 8: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/8.jpg)
2,4-D- Resistant Cotton Being Developed
2,4-D resistant cotton
2,4-D sensitive cotton
![Page 9: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/9.jpg)
Objective
• Begin to determine the most effective 2,4-D weed management systems for glyphosate-resistant Palmer amaranth.
![Page 10: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/10.jpg)
Experiments
1. Single application study (non-crop)
2. 2,4-D weed management systems (DHT cotton)
![Page 11: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/11.jpg)
Experiment 1: Single Application
Macon County(2 locations)
Tift County(1 location)
![Page 12: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/12.jpg)
Factorial Treatment Arrangement(Experiment 1: Single Application)
2,4-D (Weedar) Option: 0, 1.0, 1.5, or 2.0 pt/A
Ignite Option: 0 or 29 oz/A
Palmer was 8 inch at time of application (15 GPA)
![Page 13: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/13.jpg)
Percent GR Palmer amaranth control at 20 d. Average 3 loc., GA, 2009.
0
20
40
60
80
100
0.5 lb 0.75 lb 1.0 lb1.0 lb 0.25 lb 0.5 lb
2,4-D 2,4-D
69 cd
77 bc
73 bcd
79 b
91 a
92 a
96 a
Ignite
(29 oz)+
Ignite
![Page 14: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/14.jpg)
Non-treated Ignite
12 DAT
![Page 15: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/15.jpg)
Non-treated
12 DAT
1.5 pt 2,4-D
![Page 16: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/16.jpg)
1.5 pt of 2,4-D
12 DAT 24 DAT
![Page 17: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/17.jpg)
Non-treated Ignite + 2,4-D
12 DAT
![Page 18: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/18.jpg)
Experiment 2: Systems
PRE
Prowl
Prowl
Prowl
Prowl
POST (4-6” Palmer)
Weedar
Ignite + Weedar
Ignite
None
Residual programs
Direx + MSMA directed to all systems. Prowl 2.1 pt/A; Reflex 1 pt/A; Ignite 23 oz/A; Weedar 1.5 pt/A; Direx 2 pt/A; MSMA 2 lb ai/A.
TRT
1
2
3
4
Prowl + Reflex
Prowl + Reflex
Prowl + Reflex
Prowl + Reflex
Weedar
Ignite + Weedar
Ignite
None
5
6
7
8
![Page 19: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/19.jpg)
Experiment 2: Systems
POST 1 (4-6“ Palmer)
Weedar
Weedar + Ignite
Ignite
None
POST 2 (3-6” Palmer)
Weedar
Weedar + Ignite
Ignite
None
Total POST programs
Direx + MSMA directed to all systems. Weedar 1.5 pt/A; Ignite 23 oz/A; Direx 2 pt/A; MSMA 2 lb ai/A.
TRT
1
2
3
4
![Page 20: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/20.jpg)
One inch of rainfall occurred within 5 days of planting and PRE treatments. Rainfall continued throughout the season.
![Page 21: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/21.jpg)
Percent GR Palmer amaranth control 28 d after layby. Macon Co. GA, 2009.
0
20
40
60
80
100
86 bc
82 c
20 d
93 ab
99 a
99 a
99 a
2,4-D Ignite + 2,4-D
None
Prowl
Ignite
+ ReflexProwl ProwlProwl
+ Reflex
+ Reflex
+ Reflex
POST 2,4-D Ignite + 2,4-D
None Ignite
82 c
Direx + MSMA directed to all systems.
![Page 22: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/22.jpg)
Percent GR Palmer amaranth control at harvest. Macon Co. GA, 2009.
0
20
40
60
80
100
48 c
50 c
81 b
90 a
90 a
93 a
2,4-D Ignite + 2,4-D
None
Prowl
Ignite
+ ReflexProwl ProwlProwl
+ Reflex
+ Reflex
+ Reflex
POST 2,4-D Ignite + 2,4-D
None Ignite
43 c
Direx + MSMA directed to all systems.
![Page 23: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/23.jpg)
Seed Cotton Yield (lb/A). Macon Co. GA, 2009.
0
300
600
900
1200
490 c
530 c
955 a
1120 a
1080 a
1100 a
2,4-D Ignite + 2,4-D
None
Prowl
Ignite
+ ReflexProwl ProwlProwl
+ Reflex
+ Reflex
+ Reflex
POST 2,4-D Ignite + 2,4-D
None Ignite
140 d
Direx + MSMA directed to all systems.
![Page 24: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/24.jpg)
Percent GR Palmer amaranth control comparing POST and residual programs 28 d after layby .
Macon Co. GA, 2009.
0
20
40
60
80
10099 a
81 c
93
ab
94 a
Ignite + 2,4-D
Prowl+
Reflex
POST Ignite
Ignite
Ignite + 2,4-D 2,4-D
2,4-D
Ignite + 2,4-D
Ignite + 2,4-D
88 b
Direx + MSMA directed to all systems.
POST 2
![Page 25: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/25.jpg)
Non-treated Control (July 5)
![Page 26: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/26.jpg)
Ignite + 2,4-D
Ignite + 2,4-D
2,4-D
2,4-D
Glyphosate-resistant Palmer amaranth response to sequential POST applications. Macon Co., 2009.
![Page 27: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/27.jpg)
0
20
40
60
80
100
93 a
50 c
81 b
85 b
Ignite + 2,4-D
Prowl+
Reflex
POST Ignite
Ignite
Ignite + 2,4-D 2,4-D
2,4-D
Ignite + 2,4-D
Ignite + 2,4-D
50 c
Direx + MSMA directed to all systems.
POST 2
Percent GR Palmer amaranth control with POST programs at harvest . Macon Co. GA, 2009.
![Page 28: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/28.jpg)
0
300
600
900
1200
1100 a
440 b
955 a
1026 a
Ignite + 2,4-D
Prowl+
Reflex
POST Ignite
Ignite
Ignite + 2,4-D 2,4-D
2,4-D
Ignite + 2,4-D
Ignite + 2,4-D
550 b
Direx + MSMA directed to all systems.
POST 2
Seed cotton yields (lb/A) with total POST programs. Macon Co. GA, 2009.
![Page 29: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/29.jpg)
Summary
(Experiment 1, Single Application)
• Ignite (29 oz) controlled GR Palmer amaranth 73%
• 2,4-D (1 to 2 pt) controlled GR Palmer amaranth 69-79%
• Ignite + 2,4-D controlled GR Palmer amaranth 91-96%
![Page 30: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/30.jpg)
Summary
(Experiment 2, Systems)
• Prowl fb 2,4-D or Ignite fb Direx + MSMA controlled Palmer 50%. Mixing Ignite with 2,4-D improved control at least 31%.
• Prowl plus Reflex fb Ignite, 2,4-D, or Ignite + 2,4-D controlled Palmer 90 to 93%.
• Total POST programs with sequential Ignite or 2,4-D applications provided only 50% control. Mixtures of Ignite plus 2,4-D improved control 35%.
At harvest
![Page 31: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/31.jpg)
Summary
(Experiment 2, Systems)
Prowl fb Ignite + 2,4-D fb Direx + MSMA
Prowl + Reflex fb Ignite, 2,4-D or Ignite + 2,4-D fb Direx + MSMA
Sequential Ignite + 2,4-D applications fb Direx + MSMA
Highest seed cotton yields
![Page 32: Control of Glyphosate-Resistant Palmer amaranth in DHT Cotton](https://reader036.vdocuments.us/reader036/viewer/2022081520/56815981550346895dc6c05b/html5/thumbnails/32.jpg)
Conclusions
The addition of 2,4-D in a systems approach offers growers a significant advantage of managing emerged glyphosate-resistant Palmer amaranth
Physical movement of 2,4-D is of great concern; however, research to address this is in progress