Indian Journal of Agronomy

A field experiment was conducted during 2004–05 and 2005–06 on clay-loam soil at Jabalpur in Madhya Pradesh to find out the effect of integrated weed-management practices on weeds and yield of zero-till direct-seeded rice (Oryza sativa L.). Different methods of crop establishment were evaluated for getting higher productivity and profitability of irrigated rice-wheat cropping system. For rice there were four methods, viz. direct seeding by zero-till drill, direct drilling in friable soil by seed drill, direct seeding of sprouted seeds in puddled soil, and transplanting; and for the succeeding wheat (Triticum aestivum L. emend. Fiori & Paol.) there were two methods, viz. sowing with zero-till drill and conventional sowing. Echinochloa colona and Commelina spp. were the major weeds in zero-till, direct-seeded rice, which reduced the grain yield by 27.4%. Pre-emergence application of pretilachlor at 750 g/ha or pendimethalin at 1.0 kg/ha each, followed by one hand-weeding at 30 days after sowing was on a par with hand-weeding twice, giving significantly higher grain yield (5.20 and 3.50 t/ha) compared with the weedy check (3.98 and 2.25 t/ha). Zero-till, direct-seeded rice with proper weed management resulted in significantly higher yield than transplanted rice. In the succeeding wheat crop, population of dominant weeds, viz. Chenopodium album and Medicago hispida, was found to be reduced when wheat was grown after zero-till, direct-seeded rice compared with other methods of rice establishment. The wheat sown after zero-till, direct-seeded rice yielded significantly higher (3.76 and 3.61 t/ha) than when sown after other methods of rice establishment. Zero tillage in direct-seeded rice-wheat system reduced the weed problem and increased the system productivity as well as profitability.