Effect of herbicides on weed growth and crop performance in rice-blackgram cropping system

摘要

A field experiment was conducted to identify effective weed management practices in rice-blackgram cropping system. During kharif, application of anilophos @ 0.4 kg/ha at 5 DAT to rice was found equally effective in suppressing weed growth and resulted in grain yield of rice as that of hand weeding twice at 20 and 40 DAT. The competitional stress to rice was mainly caused by Echinocloa colona, Cyperus iria, Cyperus difformis and Ammania baccifera. During rabi, the competitional stress to blackgramwas mainly due to Cyperus rotundus, Echinocloa colonum, Panicum sp. and Trianthema portulacastrum. Application of pendimethalin, metolachlor, alachlor each @ 1.5 kg/ha to blackgram was effective in controlling weeds and resulted in similar yield as thatof hand weeded crop. All weed management treatments resulted in significantly higher seed yield over that of unweeded control. Application of herbicides and hand weeding in rice had no effect on weed growth of succeeding blackgram crop in rabi and similarly herbicide application to blackgram did not influence the weed flora and growth of rice in kharif.