Efficacy of penoxsulam against weeds in transplanted rice (Oryza sativa L.) under temperate conditions of Kashmir

Field studies were conducted to evaluate the efficacy of penoxsulam against complex weed flora both as pre-and post-emergence herbicide in transplanted rice during Kharif seasons of 2008 and 2009 at Mountain Research Centre for Field Crops, SKUAST-K, Khudwani, Kashmir (India) on a silty clay loam soil with normal reaction and medium fertility status. Major weed species infesting the field were Echinochloa crus-galli, Echinochloa colona, Cyperus iria., Cyperus difformis, Marsilea quadrifolia, Potamogeton distinctus, Ammania baccifera and Monochoria vaginalis. The experiment consisted of eight treatments replicated thrice and laid out in a randomized block design. Penoxsulum application @ 22.5 g a.i. ha⁻¹ as pre-emergence 3–5 days after transplantation (DAT) provided effective control of almost all types of weed species thereby resulting in higher paddy yield (72.8 q ha⁻¹) as compared to weed-free (77.2 q ha⁻¹) and two hand weeding (71.9 q ha⁻¹). Penoxsulam @ 20 g ai ha⁻¹ was also effective in controlling weeds when applied as post-emergence (8–12 DAT) and gave a paddy yield of 69.2 q ha⁻¹.