Influence of growth stage and dicamba rate on eggplant, cucumber, and snap bean tolerance and yield response

Abstract Following the introduction of dicamba-resistant (DR) soybean in 2017, concerns have increased with regard to dicamba off-target movement (OTM) onto sensitive crops, including vegetables. Field trials were conducted New Jersey, York, and Delaware evaluate cucumber (‘Python’), eggplant (‘Santana’), snap bean (‘Caprice’ ‘Huntington’) injury yield response simulated drift rates. Crops exposed applied at 0, 0.056, 0.11, 0.56, 1.12, 2.24 g ae ha –1 , representing 1/10,000, 1/5,000, 1/1,000, 1/500, 1/250 maximum recommended label rate (560 ), respectively. Dicamba was either early vegetative (V2) or reproductive (R1) stages. Minimal no injury, vine growth reduction, loss noted for cucumber. more injurious up 22% 35% 2 wk after treatment (WAT) ≥1.12 ; however, only highest caused 27% reduction commercial compared nontreated control. Eggplant also showed greater sensitivity when exposure occurred R1 than theV2 stage. Snap most crop investigated this study. Injury WAT ‘Caprice’ ≥0.56 V2 stage, whereas a similar difference as low 0.056 ‘Huntington’. Compared control, plant height biomass accumulation both cultivars . 1.12 resulted 30% ‘Caprice’, ‘Huntington’ dropped 52% 93% not influenced by timing application. Conversely, decreased 8% following application