Field investigations were conducted at the Punjab Agricultural University, Ludhiana during 1996–97 and 1997–98 on sandy loam soil to test the response of isoproturon resistant biotypes of Phalaris minor (24) to isoproturon 1.88 kg/ha, metoxuron 1.5 kg/ha, diclofop-methyl 0.90 kg/ha, fenoxaprop-ethyl 100 ml/ha, metribuzin 160 g/ha, clodinafop 60 g/ha and sulfosulfuron 25 g/ha. Tralkoxydim, clodinafop and sulfosulfuron showed exccllent control of various biotypes during both the years. Fenoxaprop-p-ethyl, metribuzin and diclofop-methyl also gave good control of biotypes. However, some escapes were observed during both the years in these herbicides. Isoproturon even at double the recommended dose failed to control the biotypes of P. minor. Phalaris biotypes differed in their morphological characters like plant height and dry matter accumulation.
