Xtend Cotton Response to Low Rates of 2,4-D

Weed control by use of herbicides is an important tactic in successful crop production. Two new technologies have recently entered the market that will allow producers to spray dicamba or 2,4-D over-the-top of cotton and soybean. Dicamba-tolerant soybean and cotton are commercially available and marketed as “Xtend” and 2,4-D tolerant crops will be called “Enlist”.  Although new technologies are beneficial for the control of herbicide-resistant weeds, there are concerns with the application of these herbicides with off-target movement, or drift. Field study was conducted in 2020 at the Delta Research and Extension Center, in Stoneville, Mississippi, to evaluate Xtend cotton (DP 1646 B2XF) injury at various low rates of 2,4-D (1/16 X, 1/32X, and 1/64X) and to assess which crop growth stage is more sensitive than the others. All applications were made at three cotton growth stage: 3- to 4-leaf, square, and at flowering. 2,4-D (1X) rate was 32 fl oz/A.