Response of Cotton Growth Stages from Simulated Drift Rates of 2,4-D and Dicamba

Glyphosate susceptibility in many weed species has decreased. In the coming years, row crops with genetically modified (GM) tolerance to dicamba will be available to combat glyphosate-resistant weeds. A field study was conducted at the Delta Research and Extension Center, in Stoneville, Mississippi, in 2017 to evaluate cotton (Stoneville Bollgard II 4747GLB2) response at three growth stages to simulated drift rates of 2,4-D and dicamba. Applications were made at three cotton growth stages, three- to four-leaf, at square, and at flowering. Dicamba and 2, 4-D were applied at 1/16 X and 1/32 X (simulated drift rates) rates of the labeled rate (1 X). A nontreated check was included.