Bio-efficacy of pre and post-emergence herbicides for control of complex weed flora in transplanted rice (Oryza sativa L.)

Abstract

A field experiment was conducted for two consecutive rainy seasons of 2017 and 2018 at Banka (Bihar) to evaluate the bio-efficacy of pre and post-emergence herbicides for control of complex weed flora in transplanted rice (Oryza sativa L.). The experimental field was infested with Echinochloa colona, Echinochloa crusgalli, Dactyloctenium aegyptium, Cynodon dactylon, Panicum repens, Ammania baccifera, Eclipta alba, Caesulia axillaris, Commelina benghalensis, Euphorbia hirta, Ludwigia parviflora, Cyperus iria, Cyperus difformis and Fimbristylis miliaceae. Density of grasses, broad-leaved weeds, sedges and total weeds at 60 DAT was recorded lower with pretilachlor 750 g/ha fb 1 hand weeding at 25 DAT and which was statistically comparable with butachlor 1500 g/ha fb1 hand weeding at 25 DAT among weed management treatments excluding hands weeding twice at 20 & 40 DAT and weed free during both the years of experiment. Biomass of grasses, broad-leaved weeds, sedges and total weeds was registered less in pretilachlor 750 g/ha fb 1 hand weeding at 25 DAT and which was significantly superior to all weed management treatments excluding hands weeding twice at 20 & 40 DAT and weed free during both the years of experiment. More panicle weight, panicle length, grains/panicle, grain and straw yield was observed with application of pretilachlor 750 g/ha fb1 hand weeding at 25 DAT.