Study the Effects of Different Weed Control Methods on Yield and Yield Components of Rice

In order to study the effects of several weed control methods on yield and yield components of rice، a field experiment was carried out in Babol city- during 2011. The experiment was on the basis of randomized complete blocks design with 3 replications and 7 treatments including hand weeding twice، powered weeding twice، powered weeding+hand weeding، conoweeder weeding twice، herbicide application+hand weeding، weedy check and herbicide application only were used. Results showed that there was significant difference among treatments on grain yield، grain number per panicle، filled grain number per panicle، unfilled grain number per panicle، fertile tillers، panicle number، biological yield، density and dry weight of weed. In general herbicide application+hand weeding produced highest grain yield، while weedy check with high unfilled grains per panicle، less panicle number، and highest density and dry weight of weed had less grain yield. Among the mentioned traits، fertile tillers and panicle number had the highest correlation with grain yield. Unfilled grain number per panicle، density and dry weight of weed، had negative and significant correlation with grain yield.