Response of transplanted rice to nitrogen fertilization under different weed management practices

Abstract

Rice yield increased significantly and consistently up to 120 kg N/ha when weeds were not controlled. But when weeds were effectively controlled by two hand weedings (20 and 40 days after transplanting) or by use of thiobencarb at 1-0 kg a.i./ha rice yield increased significantly up to 80 kg N/ha. The optimum dose of N for transplanted rice under mid-hill conditions of Himachal Pradesh (Palampur) was 82 kg/ha when two hand weedings were done and 86 kg/ha when weeds were managed using thiobencarb. The yield response per kg of N in the respective treatments was 20 and 24 kg of grain. The weed dry weight was significantly lower in thiobencarb and hand weeded plots compared with unweeded check though the difference in weed dry weight due to the former two treatments was not significant.

Yield Component Analysis of Direct Seeded Rice Under Several Densities of Red Sprangletop (Leptochloa chinensis(L.) Nees (in Peninsular Malaysia.

“…Competition for light, water and nutrients are certainly major factors accounting for the adverse effect of weeds on crop growth and yield17, 18,24). The degree of weed competition is related in part to the weed species, its density, and the length of the competition period11).…”