Uncontrolled weeds caused 31% reduction in grain yield of rice. Pyrozosulfuron-ethyl at 20, 25 or 30 g ha−1 was as effective as butachlor at 1250 g ha−1 but superior to hand weeding and rotary paddy weeder in reducing weed growth and increasing grain yield of rice. The yield obtained from hand weeding was comparable to rotary weeder.
