Effect of different pre and post-emergent application of herbicides on the productivity of Black gram (Vigna mungo L.) under acidic soils of Manipur

Abstract

A field experiment on “Effect of different pre and post-emergent application of herbicides on the productivity of Urd bean under acidic soils of Manipur” was conducted at Central Agricultural University (CAU) research farm, Andro, Imphal, Manipur. The experiment was carried out in randomized block design with eleven treatments viz weedy-check, 2 hands weeding at 20 and 40 DAS, pre-emergent application of pendimethalin 30%EC @ 1.0 kg/ha, Quizalop ethyl 75 g/ha as post-emergent application, Fenoxyprop-p-ethyl-ethyl 50g/ha as a post-emergent spray, pendimethalin + Imazathapyr 0.75 kg/ha, pendimethalin + Imazathapyr 1 kg/ha, Imazathapyr 250 ml/ha at 15 DAS, Imazathapyr 400 ml/ha at 15 DAS, Imazathypr 55 g/ha as post-emergent sprays and weed-free check. The results point out that the treatment weed-free check recorded significantly higher seed (629.2 kg/ha) and stover yield (1807.2 kg/ha) which was consistent with pendimethalin 30% EC + Imazathapyr 2% EC @ 1 kg a. i. per ha (602 & 1724 kg/ha respectively) besides other yield attributes. These treatments were recorded a substantial reduction in weed count and weed dry matter. Furthermore, weed control efficiency was significantly higher at 30 & 45 DAS, and weed index was lowest compared to other treatments. The two-year study concludes that pre-emergent application of a ready mixture of pendimethalin 30% EC + Imazethapyr 2% EC @ 1 kg a. i. per ha. + one hand weeding at 25-30 DAS and post-emergent application of Imazathypr 55 g a.i. per ha is the most effective treatment in controlling weeds under Manipur conditions.