Effect of Herbicides on Weed Control and Grain Yield of Wheat in Mid-Himalayan Conditions1

Five herbicides were evaluated for their weed control efficacy and influence on wheat grain yield for three winter seasons of 1978–79, 1979–80 and 1980–81 at Hawalbagh, Almora. Use of methabenzthiazuron, Metoxuron and Isoproturon caused significant reduction in weed biomass production resulting in increased grain yields. Weed control efficacy was lower in hand weeding, terbutryn and diclofop-methyl treatments. The highest mean grain yield was obtained with isoproturon at 1.00 kg/ha and metoxuron at 1.75 kg/ha (both as post-emergnce) and the lowest in unweeded check followed by hand weeding once. A low degree of phytotoxicity was observed in wheat with terbutryn and diclofopmethyl.