Yield Improvement of Kharif Rice by Different Weed Management Practices

Abstract

A field experiment was conducted during kharif 2017 at the Agricultural Farm, Palli Siksha Bhavana, Visva-Bharati, Sriniketan, Birbhum, West Bengal to study the effect of different weed management practices on yield improvement of transplanted kharif rice. Nine treatments viz; pretilachlor 500 g/ha as pre emergence, oxadiargyl 90 g/ha as pre emergence, pyrazosulfuron ethyl 25 g/ha as pre emergence, pretilachlor 500 g/ha as PE followed by hand weeding at 40 DAT, oxadiargyl 90 g/ha as PE followed by hand weeding at 40 DAT, pyrazosulfuron ethyl 25 g/ha as PE followed by hand weeding at 40 DAT, hand weeding twice at 20 and 40 DAT, weed free and unweeded control were tested in randomized complete block design with three replications. The predominant weed flora present in the experimental field was Echinochloa glabrescens, Cyperus difformis, Cyperus iria and Ludwigia parviflora. All weed control treatments significantly reduced the population and dry weight of all categories of weeds viz., grasses, sedges and broadleaf weeds than unweeded control which resulted significant increase in different growth parameters of transplanted kharif rice. Among the herbicide applied treatments, pyrazosulfuron ethyl 25g/ha fb one hand weeding at 40 DAT resulted in significantly higher values of plant height, leaf area index, dry matter accumulation, crop growth rate and ultimately grain yield (5.22 t/ha) of rice than that of unweeded control. Hand weeding at 20 and 40 DAT was statistically at par with pyrazosulfuron ethyl 25g/ha fb one hand weeding at 40 DAT.