Effect of planting method, tillage and weed management on productivity and physico-chemical properties of rice (Oryza sativa) – wheat (Triticum aestivum) cropping system

A field experiment was conducted during 2002–03 and 2003–04 at Raipur in Chhattisgarh to assess the productivity of rice (Oryza sativa L.) – wheat [Triticum aestivum L. emend. Fiori & Paol.] cropping system and changes in soil-nutrient status due to different planting methods of rice and tillage and weed-management practices of wheat. Transplanting of rice after Sesbania aculeata (green manure, GM) incorporation (Rice_GM-TP) produced significantly higher grain yield of rice (19.5–25.3%) and increased the organic C, available N and K over transplanting of rice (Rice_TP) and beushening system without GM (Rice_BS). The residual effect of Rice_GM-TP gave 11.1% higher grain yield of wheat, increased the available N, P and K content in the soil and reduced the bulk density in 0–7 and 10–17 cm soil depths. Conventional tillage (Wheat_CT) in wheat produced 19.1% higher grain yield than zero tillage (Wheat_ZT). Zero-tilled wheat gave 10.7% higher organic C in the soil than Wheat _CT. Infiltration rate was the highest under Wheat_CT and observed to be 20.5% higher at harvest. Post-emergence application of sulfosulfuron @ 25 g/ha and metsulfuron-methyl @ 4 g/ha reduced the dry weight of weeds significantly over the weedy check and increased the grain yield of wheat. Transplanting of rice after GM incorporation followed by conventional tillage and post-emergence application of sulfosulfuron in wheat improved the soil physico-chemical properties and gave the maximum total productivity (12.45 t/ha) and net returns (Rs 52,104/ha).