Weed control method for semi-dry dibbled crop of rice

Abstract

An experiment was. conducted at the nice Research station of Kerala Agricultural university at Kayamkulam during, the Virippu (first crop) season of 1981-82 to find out a suitable weed control method for semi-dry dibbled crop of rice, in simple randomised block design with 7 herbicide treatments. 4 hand weeding treatments of which one was the local practice and another unweeded control. Monocot weeds were found to be better competitors than dicot weeds. Heed population was maximum during the first 40 days of dibbling. The herbicides reduced weed population and dry matter accumulation compared to hand weeded plots and increased the weed control efficiency. All the crop growth characters like plant height tiller count and LAI were Influenced favourably by the application of herbicides compared to hand weeding. Yield attributing factors like number of productive tillers/hill, length of the panicle, weight of the panicle and number of filled grains per panicle were adversely influenced by competition with weeds and control of weeds by the use of herbicides like benthiocarb 2.0 kg ai/ha and nitrofen 1.975 kg ai/ha increased the yieldattributing character® which was reflected on the grain and straw yield.