The Effect of Simulated 2,4-D Drift at Various Growth Stages on Plant Height and Yield of Cotton

With the impending release of 2,4-D resistant cotton cultivars, the interface between tolerant and non-tolerant cotton cultivars will be inevitably be increased, raising concern over the impact of 2,4-D drift on cotton.  Furthermore, with the diverse cropping systems and a wide range of planting dates utilized throughout the cotton belt, a multitude of scenarios exist in which various growth stages of cotton could be exposed to 2,4-D drift from neighboring applications. Cotton is known to be one of the most sensitive plants to 2,4-D.  Preliminary data suggests that the concentration of active ingredient present in simulated 2,4-D drift has a strong influence on yield, however it is also clear that the growth stage in which drift occurs may have an equal or greater effect on yield.