Abstract:
Field experiments were conducted during Kharif (wet) seasons of 2014 and 2015 at Agricultural Farm, Institute of Agriculture, Visva-Bharati, Sriniketan, West Bengal, with rice variety 'MTU-7029' to study the effect of sole and combined application of different herbicides on growth of composite weed flora and productivity of wet season transplanted rice. Eleven treatments were assigned in a randomized block design with three replications. Echinochloa colona and Paspalum distichium among the grasses; Cyperus iria, among the sedges and Ludwigia parviflora among the broad-leaved weeds were predominant throughout the cropping period. Azimsulfuron at 35 + 2, 4-D at 500 g/ha at 25 DAT effectively controlled the complex weed flora recorded at 50 DAT which was statistically at par with pretilachlor at 750 g + pyrazosulfuron-ethyl at 25 g/ha at 3 DAT. Weed competition reduced the grain yield of rice to the tune of 33-35%. Lower values of weed density, total weed dry weight and higher values of weed control efficiency and yield of rice were registered with combined application of azimsulfuron at 35 g + 2, 4-D at 500 g/ha at 25 DAT and it was followed by pretilachlor at 750 g + pyrazosulfuron-ethyl at 25 g/ha at 3 DAT. These treatments could be recommended for managing complex weed flora and obtaining higher yield of transplanted Kharif (wet) rice in the lateritic belt of West Bengal, India
