Weed management in transplanted rice (Oryza sativa) under rainfed, lowland situation

Abstract

A field experiment was conducted during wet season of 1996 and 1997 to study the effect of various weed-management practices on yield, weed growth, and nitrogen uptake by rice (Oryza sativa L.) and weeds in transplanted situation condition. Keeping the weed-free-up to 60 days after transplanting (DAT) and application of Anilofos 0.4 kg a.i.lha followed by hand-weeding at 40 DAT resulted in at par and significantly higher grain yield and nitrogen uptake over rest of the treatments. Among chemical weed-control methods, minimum weed density and dry weight were recorded with Anilofos 0.4 kg a.i.lha applied as pre-emergence supplemented with 1 hand-weeding at 40 DAT. Weedy check till maturity reduced the grain yield by 49% while minimum reduction was recorded with Anilofos 0.4 kg a.i.lha + 1 handlweeding at 40 DAT (4%) as compared to weed-free up to 60 DAT. Weedy check till maturity removed significantly highest nitrogen through weeds (12.97 kglha). Pre-emergence spray of Anilofos 0.4 kg a.i.lha + 1 hand-weeding at 40 DAT resulted in higher net income and benefit : cost ratio.