Effect of low doses of herbicides on weeds, nutrient uptake and yield of transplanted rice (Oryza sativa)

A field experiment was conducted during the rainy season of 2001 and 2002 at Research farm of Institute of Agricultural Science, Banaras Hindu University, Varanasi. Pre-emergence application of mixture of almix + 2,4-DEE 15 + 500 g/ha recorded the minimum weed density and their biomass than rest of the herbicidal treatments. This treatment registered higher weed-control efficiency next to hand-weeding thrice. Hand-weeding and chemical weeding treatment with almix + 2, 4 DEE 15 + 500 g/ha significantly increased the nutrient uptake by crop and gave higher grain yields. However, the minimum nutrient uptake by crop was noted under unweeded check. On an average, almix + 2, 4-DEE 15 + 500 g/ha registered 88 and 83% higher grain yield in 2001 and 2002, respectively, compared to weedy check.