Effect of Doses and Stages of Application of Pyrazosulfuron Ethyl on Weeds in Transplanted Rice

Pyrazosulfuron ethyl at 20 and 25 g ha−1 significantly reduced the weed density and total weed dry weight of Cyperus iria, Sphenochlea zeylanica, Echinochloa colona and Leptochloa pamica when applied 3 to 10 days after transplanting (DAT). These treatments provided grain yield statistically similar to weed free treatment. Efficacy of herbicide was reduced when applied 20 DAT resulting in less grain yield.