Abstract

A field experiment was conducted during kharif season of 2002 to find out the effective dose and stage of application of cyhalofopbutyl at 80, 100 and 120 g ha^-1, quinclorac at 125, 187.5 and 250 g ha^-1, clefoxydim at 50, 75 and 100 g ha^-1 applied at 15 DAS and  pretilachlor at 0.5, 0.75 and 1.0 kg ha^-1, pendimethalin at 1.0 kg ha^-1 applied as pre-emergence for studying their effect on yield attributes and grain yield of dry seeded rice (Oryza sativa L.). Highest yield attributes and grain yield (62.8 q ha^-1) were observed under weed free condition followed by pendimethalin at 1.0 Kg ha^-1 (54.0 q ha^-1). The lowest grain yield (0.85 q ha^-1) was recorded in weedy check. Higher doses of cyhalofopbutyl, quinclorac, clefoxydim and pretilachlor recorded significantly higher yield attributes and grain yield than their respective lower doses. Uncontrolled weed growth caused 98.64% reduction in grain yield of rice. None of the treatments could produce grain yield at par with weed free treatment and pendimethalin at 1.0 Kg ha^-1 proved to be more promising than all other herbicides.

Key words: Dry seed, herbicide, rice, weed.