Indian Journal of Agronomy

A field experiment was conducted during the winter (rabi) season of 2000–01 and 2001–02 to assess the efficacy of oryzalin, trisulfuron and pendimethalin as pre-emergence, and dicamba as post-emergence in late-sown wheat (Triticum aestivum L. emend. Fiori & Paol.). All herbicidal treatments reduced the density and dry weight of both narrow and broad-leaf weeds significantly from weedy check. Pre-emergence application of oryzalin at 1.25 kg/ha had minimum population and dry weight of weeds than other herbicides and doses. Dicamba at 0.025 kg/ha was the most effective against broad-leaf weeds. Trisulfuron at 0.020 kg/ha proved more effective than it's lower dose (0.015 kg/ha) and controlled both narrow and broad-leaf weeds. Negative correlation (r = –0.82) was observed between weed biomass and grain yield of wheat. Oryzalin 1.25 kg/ha was most effective in enhancing yield attributes and had maximum grain (27.48 q/ha) and straw yields (49.21 q/ha). Amongst the weed-control treatments, an application of oryzalin at 1.25 kg/ha recorded the maximum net returns (Rs 27,713) and benefit:cost ratio (2.7).