Sequential application of herbicides in wheat (Triticum aestivum) underpeninsular Indian conditions

摘要

A field experiment was conducted during the winter (rabi) season of 2014 at a farmer's field in Muttagi Village, Vijayapur District, Karnataka, to study the effect of sequential application of pre (pendimethalin, metribuzin) and post-emergence (2,4-D, metsulfuron methyl) herbicides on weed growth, crop growth parameters and yield of wheat (Triticum aestivum L.) under irrigated situation. Unchecked weed growth caused 25.04% reduction in grain yield of wheat. Pre-and post-emergence herbicides applied in sequence proved more effective in reducing population and total dry matter of weeds and recording higher weed-control efficiency as compared to their sole application. Maximum grain yield of wheat was recorded from weed-free check (4.3 t/ha), which was atpar with pendimethalin @ 1 kg/ha followed by metsulfuron-methyl @ 4 g/ha, pendimethalin @ 1 kg/ha followed by 2,4-D @ 2 kg/ha and pendimethalin @ 1 kg/ha followed by 1 intercultivation at 30 days after sowing. Higher grain yield was a reflection of higher plant height, effective tillers/m, total dry-matter production and higher N, P, K uptake by wheat in these treatments. Pre-emergence application of metribuzin @ 175 g/ha was phytotoxic (scale 3 at 14 days after spraying) to wheat crop.