A dual tank precision sprayer to evaluate the interaction of 2,4‐D choline and quizalofop‐p‐ethyl for control of volunteer corn in corn

Abstract Quizalofop‐p‐ethyl (QPE) can control glufosinate/glyphosate‐resistant corn ( Zea mays L.) volunteers in corn resistant to aryloxyphenoxypropionates (Enlist corn). Mixing QPE with broadleaf herbicides such as 2,4‐D choline can be antagonistic. A new precision sprayer with a dual tank/boom system can apply two herbicides simultaneously through separate nozzles, potentially reducing chemical antagonism. The objective of this study was to evaluate the interaction of QPE + 2,4‐D choline applied via single tank or dual tank/boom system for controlling glufosinate/glyphosate‐resistant corn volunteers in Enlist corn. Bin‐run glufosinate/glyphosate‐resistant corn was planted at 54,000 seeds ha −1 to mimic corn volunteers. At 14 days after application (DAA), the dual tank/boom application of QPE (39 g a.i. ha −1 ) and 2,4‐D choline (1064 g a.e. ha −1 ) achieved 85% volunteer corn control, compared to 70% control with single tank mix. The single tank application of QPE + 2,4‐D choline was 7%–26% antagonistic until 28 DAA. Conversely, dual tank application of QPE and 2,4‐D choline was additive. Although dual tank application of QPE and 2,4‐D choline did not have transient antagonism (14 DAA), it was otherwise eliminated by 28 DAA using the higher rate of QPE (77 g a.i. ha −1 ) in the tank mix. By 28 DAA, volunteer corn control was ≥92% across all treatments, with similar corn yield and no crop injury. The results suggest that a dual tank/boom system provided better volunteer corn control at 14 DAA; however, control was similar when using a higher rate of QPE (77 g a.i. ha −1 ) with 2,4‐D choline in tank mix at 28 DAA.