Weed management in late-sown zero-till wheat (Triticum aestivum) with varying seed rate

Excessive tillage and soil degradation are important factors limiting wheat [ Triticuam aestivum (L.) emend. Fiori & Paol.) productivity, particularly in rice ( Oryza sativa L.) wheat cropping system. Therefore present field experiment was conducted during winter of 2007-08 and 2008-09 at Varanasi to study the effect of seed rate and weed management on weed growth and yield in late sown zero till wheat. Treatments comprised of three seed rates viz.,100,120 and 140 kg/ha in the main plots and five weed management treatments viz., weedy, 2,4-D Na salt 625 g/ha (POE), metsulfuron methyl 4 g/ha (POE) , sulfosulfuron 30 g/ha + metsulfuron methyl 2 g/ha (POE) and 2-hand weedings in sub-plots with three replications. Broad leaved weed population was found more in the experimental crop as compared to narrow leaved weeds. All the herbicidal treatments were effective in reducing weed density and dry weight in comparison to weedy check. Seed rate of 120 kg /ha recorded significantly higher grain yield in comparison to seed rate of 100 and 140 kg/ha. Amongst weed management treatments all the herbicidal weed control had significantly higher grain yield in comparison to weedy check. Sulfosulfuron 30 g/ha + metsulfuron methyl 2 g/ha had higher grain yield than alone application of 2, 4-D @ 625 g/ha and metsulfuron methyl 4 g/ha.