Effectiveness of Pre-Emergence Application of Weedicides in Upland Rice
Abstract
Eight new chemical weedicides were tested in upland rice crop at the Rice Research Farm, Agricultural Research Institute, Kanke, Ranchi. Among the annual weeds Digitaria longiflora and Echinochlaa crus-galli alone accounted for 48 and 36 percent of the total weed population respectively as observed under Butachlor (Control). G-288, USB 3584 and oxadiazon were significantly more effective than others in controlling the weeds. However, none of these weedicides could control Cyperus rotundus effectively. Effectiveness of weedicides in terms of grain yield were at par with hand weeding whereby 25.54 to 30.20 q/ha were recorded as against 6.20 q/ha in control. Lowest dry matter of weeds (5 q/ha) were recorded in C-288 treated plots but it did not enhance the production of effective tillers, apparently due to some toxic effect of the weedicide.
