Research Station Majhera, G. B. Pant University of Agriculture & Technology, Pantnagar - 263 145, India.
Field experiment was conducted for five years 1989–90 to 1993–94 at Research Station Majhera, G. B. Pant University of Agriculture and Technology, Pantnagar, Nainital. Pelldimethalin at 1.5 kg/ha as pre-emergcnce caused maximum reduction in biomass production of weeds and increased the grain yield of wheat which was statistically at par with two hand weedings and isoproturon at 1.5 kg/ha applied as post-emergence under lower valley situation of U. P. hills. The highest mean (pooled basis) weed control efficiency of 74.6% was obtained with the application of pendimethalin at 1.5 kg/ha. Pendimethalin and isoproturon at their lower doses (0.5 kg/ha each) were also found significantly superior over the weedy check in increasing the grain yield.