Effect of integrated weed-management practices on growth and yield of wet- seeded rice (Oryza and their residual effect on succeeding pulse crop sativa)

Abstract

A field experiment was conducted at Agricultural College and Research Institute, Madurai during winter (rabl) seasons of 1998-99 and 1999-2000, to study the effect of integrated weed-management practices on weed control and yield of wet-seeded rice. Glyphosate (1.5 kg a.i./ha) was applied at pre-sowing stage alone or in combination with pre-emergence application of pretilachlor +Safener (0.4 kg a.i./ha) and early post-emergence application of butanil (3 litresfha) along with manual weeding. It was compared with weed-free check and unweeded control. All the weed-management practices significantly reduced the weed density of grasses, sedges and broad-leaf weeds, resulting in their reduced dry weight. Pre-sowing application of glyphosate (1.5 kg a.i./ha) effectively reduced the sedges, when combined with pre-emergence application of pretilachlor + Safner (0.4 a.i./ha) followed by two hand-weedings at 25 and 45 days after sowing. These recorded lesser weed density, dry weight and higher weed-control efficiency, resulting in higher grain yield (58.73 qfha). Bioassay showed no residual effect of the herbicides applied to rice (Oryza sativa L.) on the stand of succeeding crop of blackgram [Phaseolus mungo (L.) Wilczek].