Effect of Post Emergence Herbicides on Weed Management in Transplanted Kharif Rice (Oryza sativa L.) and Their Residuality on Soil Microorganisms

The field experiments were conducted at Regional Research Sub-Station (new alluvial zone) of Bidhan Chandra Krishi Viswavidyalaya, Chakdaha, Nadia, West Bengal during kharif of 2015 & 2016 to study different post emergence herbicides against weed management in transplanted kharif rice. Ten (10) treatments were used following Randomize Block Design (RBD) with three replications. Among four different chemical herbicides Almix 20 WP @ 4 g ha-1 applied at 15 DAT as EPOE( early post emergence) effectively controlled all categories of weeds (mostly sedges and broad leaves) resulted minimum weed population, biomass production and higher weed control efficiency (WCE) at 30 and 45 DAT which ultimately produced higher grain yield (3.23 t ha-1) compare to other treatments. In case of efficacy of phytotoxicity effects on experimental crop, toxicity effects on soil microflora and BC ratio, Almix 20 WP @ 4 g/ha reflects the satisfied result.