Weed management in transplanted rice (Oryza sativa) and its residual effect on weed and yield of succeeding wheat (Triticum aestivum)

A field experiment was conducted during 2000–2001 and 2001–2002 to study the comparative performance of different weed-control measures for weed control in rice (Oryza sativa L.) and wheat (Triticum aestivum L. emend. Fion & Paol.) as well as residual effect of treatments (applied to rice) on weeds and yield of wheat. There was severe competition between Echinochloa crus-galli (L.) P. Beauv., E. colonum (L.) Link, and rice and between Phalaris minor (Retz.) Pers. and wheat. Unchecked weeds caused 62.6 and 25.4% reduction in grain yield of rice and wheat respectively. Maximum rice yield of 67.09 and 65.45 q/ha was recorded with hand-weeding, respectively, during both the years. Flufenacet and anilofos were the next best treatments. The residual effect of treatments (applied to rice) was not well pronounced on weed population, weed biomass accumulation and yield of wheat during both the years. Metribuzin showed the most potent direct effect and caused the maximum decrease in weed population and weed biomass accumulation, but had adverse effect on growth and yield of wheat. Hand-weeding resulted in the highest increase in wheat yield followed by sulfosulfuron.