Weed Control in Direct Seeded Rice Using New Herbicide Combination under Indian Tropical Condition

Abstract

Direct seeded rice (DSR) is gaining momentum in India due to acute labour shortage during the peak period of transplanting and shortage of water. Weeds are the major biological constrain in DSR and its management contributes a major share in cost of production, as crop and weed emerge simultaneously and exerts competition right from the beginning of the crop. Field experiments were conducted in rabi 2013 and 2014 to study the effect of new herbicide combination, bispyribac sodium + metamifop 14% SE on weed control in DSR and their residual effect on succeeding greengram. Results revealed that the post-emergence (POE) application of herbicide combination, bispyribac sodium + metamifop 14% SE at 70 g ha-1with wetter recorded significantly lower total weed density (25.78 and 24.19 plants m-2 respectively, during 2013 and 2014), total weed biomass (24.89 g m-2 and 34.56 g m-2 respectively, during 2013 and 2014) and higher weed control efficiency (80.07 and 81.68% respectively, during 2013 and 2014). Application of bispyribac sodium + metamifop 14% SE at 70 g ha-1 along with wetter (100 mL ha-1) recorded higher grain yield of 5676 and 6388 kg ha-1 respectively, during both the years. Weedy check recorded the lower grain yield and recorded the higher weed index of 51.83 and 52.85% respectively, during both the years. Succeeding crop of greengram was not affected by the residue of bispyribac sodium + metamifop 14% SE at all the tested doses.