Bio-efficacy of Herbicides against Isoproturon Resistant Biotypes of Phalaris minor in Wheat

Diclofop-methyl, sulfosulfuron, tralkoxydim, fenoxaprop and pendimethalin provided effective control of isoproturon-resistant biotypes of Phalaris minor in wheat. Grain yield of wheat obtained with isoproturon, fenoxaprop and diclofop-methyl was at par. Significant increase in grain yield of wheat under pendimethalin, sulfosulfuron and tralkoxydim over that under isoproturon was supported by more number of effective tillers and other yield contributing characters. All herbicidal treatments performed better than isoproturon in terms of control of isoproturon-resistant biotypes of P. minor. Four biotypes of P. minor (3 isoproturon-resistant and 1 isoproturon-susceptible) behaved similarly in their growth, response to herbicides and effect on wheat yield.