Productivity and economics of wheat (Triticum Aestivum) as influenced by weed management and seed rate

A field experiment was conducted during the winter (rabi) seasons of 2005–06 and 2006–07 at Varanasi, Uttar Pradesh, to assess the effect of four seed rates viz. 75, 100, 125 and 150 kg/ha on wheat (Triticum aestivum L. emend. Fiori & Paol.) productivity and to evolve efficient weed control method involving mechanical weeding at 15 and 30 days after sowing (DAS), rice straw mulch (2 tonnes/ha), neem oil spray (3%) at 30 DAS, sulfosulfuron (25 g/ha) at 30 DAS and weedy check. Increasing seed rates from 75 to 150 kg/ha significantly decreased dry weight of weeds in wheat. On an average, use of 125 kg/ha seed rate, being on a par with 100 kg seed/ha, gave significantly 20 and 26% higher grain yield than 75 and 150 kg seeds/ha, respectively. Maximum net return, benefit: cost ratio and NPK uptake by wheat was obtained with 125 kg seed/ha. Among weed control methods, mechanical weeding twice at 15 and 30 DAS proved the most effective treatment in reducing weeds dry weight which was on a par with sulfosulfuron 25 g/ha, and gave significantly higher grain yield and NPK uptake by wheat than weedy check. Mechanical weeding at 15 and 30 DAS registered the highest (35.4–45.1 per cent) increase in grain yield over weedy check, but highest net return (Rs.27,620-32,224/ha) and benefit: cost ratio (1.79–1.85) was obtained with sulfosulfuron (25 g/ha) application. It was concluded that application of sulfosulfuron 25 g/ha at 30 DAS and 125 kg seeds/ha is an efficient method for improving weed control, productivity and profitability of wheat.