Effect of Weed Management Practices on Weed Control, Yield and Economics of Soybean [Glycine max (L.) Merrill]

The experiment was laid out Tirhut College of Agriculture, farm Dholi, Muzaffarpur, Bihar during kharif season 2016, to study the effect of weed management practices on weed control, yield and economics of soybean [Glycine max (L.)]. Hand weeding twice at 25 and 45 DAS was found most effective to control weeds in soybean and recorded lowest weed count, weed dry matter and highest weed control efficiency. Among herbicide, application of Pendimethalin 1.0 kg/ha as PE (Pre-emergance) and Imazethapyr 55 g/ha as PoE (Post-emergance) at 25 DAS was found to be more efficient and cost effective to reduce weed population/m2 (53.94 & 67.22), dry weight of weeds/m2 (21.16 & 45.86 g) an increased weed control efficiency (53.86 & 68.83%) significantly in both the stages 30 and 60 DAS. Beside it, Pendimethalin 1.0 kg/ha + Imazethapyr 55 g/ha at 25 DAS, Pendimethalin 1.0 kg/ha + one hand weeding at 40 DAS and hand weeding twice at 25 and 45 DAS were equally efficient in increasing the grain yield, straw yield, weed index and gross returns than control but net returns (39870/ha) and benefit-cost ratio (1.70) was obtained maximum only with Pendmethalin 1.0 kg/ha and Imazethapyr 55 g/ha at 25 DAS.