Control Efficacy of Ethoxyfen-ethyl on Weeds of Soybean

Ethoxyfen-ethyl which is diphenylether herbicide is developed by Budapest Chemical,it's mechanism of action is protox inhibitor,it can control weeds in soybean,peanut,english pea,winter wheat and winter barley.Ethoxyfen-ethyl's biological activity is highest and it's applied range is the widest among diphenylether herbicide.Ethoxyfen-ethyl is post-applied herbicide.Ethoxyfen-ethyl's biological activity is higher than most herbicide.Ethoxyfen-ethyl mainly control annual broadleaf weeds,and it can inhibit perennial weeds to some extent.To discuss utilization technology for the herbicide ethoxyfen-ethyl applied in soybean(Glycine max),greenhouse pot experiments were conducted to investigate control efficacy,safety to soybean,effect on succeeding crop and effect of methylated vegetable oil on ethoxyfen-ethyl's activity.In greenhouse pot experiments,ethoxyfen-ethyl 30% aqueous solution had a good control effect to broadleaf weeds by foliar treatment,control efficacy occurred rapidly,injury symptoms occurred at the day after treatment,injury weed leaves occurred brown spot.Ethoxyfen-ethyl's activity of 20 mL a.i.·ha-1was higher than that of fomesafen 25% aqueous solution of 300 mL a.i.·ha-1.Ethoxyfen-ethyl visible control at 20-30 mL a.i.·ha-1 to broadleaf weeds was 78%-82.5% 4 d after treatment,88%-91% 7 d after treatment.Ethoxyfen-ethyl also had some activity on grass weeds.Ethoxyfen-ethyl caused certain injury on soybean,the injury increased with application rate increased,soybean could recover safely from injury,few soybean applied by ethoxyfen-ethyl with high concentrate(100,120 mL a.i.·ha-1)was dead,injury was similar to that of acifluorfen.Ethoxyfen-ethyl had no residue in soil and it is safe to succeeding crop such as maize(Zea mays L)and wheat(Triticum aestivum L.).Ethoxyfen-ethyl applied with methylated vegetable oil provided a dramatic increase in weeds control efficacy.Concern of both control efficacy and injury,the optimal application rate of ethoxyfen-ethyl 30% aqueous solution is 20~30 mL a.i.·ha-1 applied in soybean,and ethoxyfen-ethyl should be applied with 0.5% spray volume methylated vegetable oil.