Department of Agronomy, G. B. Pant University of Agriculture and Technology, Pantnagar-263 145, U.P., India
1 Research paper No. 4971 through the Experiment Station, G. B. Pant Univ. of Agri. £ Tech, Pantnagar, Nainital (U.P.) India.
Efficiency of butachlor at three rates of application under three seed rates of rice was evaluated for weed control in upland rice. Echinochloa colonum. Cyperus iria and Trianthema monogyna being the major weed species, uncontrolled weeds caused 97.2% reduction in rice yield. Increasing rates of butachlor from 1.5 to 2.5 kg/ha significantly reduced the density and dry weight of weeds. Seed rates of rice did not affect the density but higher seed rates reduced dry weight of weeds. Seed rates of rice did not affect the density but higher seed rates reduced dry weight of weeds.
Grain yield was higher at 150 and 200 kg seed/ha than at 100 kg seed/ha. Higher yield was obtained due to butachlor 2.0 kg/ha at 200 ka seed/ha and 2.5 kg/ha at 150 and 200 kg
