MON 37500 efficacy as affected by rate, adjuvants, and carriers

Field research was conducted to determine effects of application rate, spra y adjuvants, and spray carriers on visible control of downy brome, jointed goatgrass, and cheat and potential injury to wheat by MON 37500. MON 37500 at 24 and 46 g/ha with and without a methylated seed oil or nonionic surfac tant and carriers of water, urea ammonium nitrate (UAN), and a 1:1 water/ U AN combination were applied to the weeds at the one- to four-leaf stage. Ch eat was the most susceptible weed to MON 37500, with control consistently a bove 87% with all treatments except MON 37500 at 24 g/ha in water 26 weeks after treatment. Downy brome control was more variable, with ratings rangin g from 50 to 99% among treatments. For jointed goatgrass, only moderate stu nting was observed from all MON 37500 applications. Both wheat varieties sh owed early season injury after MON 37500 was applied with UAN and either ad juvant; however, no visible injury or yield reduction to either wheat varie ty was noticed at harvest.