Management of composite weed flora of transplanted rice by herbicides

The experiment comprising of twelve treatments was laid out in a randomized block design with three replications. Prominent weeds were Echinochloa colona and Digitaria sanguinalis among the grasses; Cyperus iria, among the sedges and Spilanthes acmella and Ludwigia parviflora among the broadleaved weeds throughout the cropping period. Fenoxaprop-p-ethyl at 60 g/ha + metsulfuron-methyl + chlorimuron-ethyl at 4 g/ha at 25 DAT effectively controlled the grasses, broad-leaved and sedges at 50 DAT which was statistically at par with the azimsulfuron at 40 g/ha at 20 DAT. The loss of grain yield of rice due to weed infestation was to the tune of 35–38%. Lower values of weed density, total weed dry weight and higher values of weed control efficiency, yield and net return of rice were registered with combined application of fenoxaprop-p-ethyl at 60 g/ha + metsulfuron-methyl + chlorimuron-ethyl at 4 g/ha at 25 DAT and was followed by sole application azimsulfuron at 40 g/ha at 20 DAT. These treatments may be recommended for managing composite weed flora and obtaining higher yield and net return of transplanted Kharif (wet) rice in the lateritic belt of West Bengal, India.