Concurrent growing of green manure with wet-seeded rice for cost-effective weed management

Field experiments were conducted during 2004–06 at Agricultural Research Station, Mannuthy, Thrissur, Kerala to find out the effect of concurrent growing of dhaincha (Sesbania aculeata) and its methods of incorporation on weed management in wet seeded rice. Sowing of rice and dhaincha was done in alternate rows using the rice-cum-green manure seeder. Treatments consisted of incorporation of dhaincha at 20 and 30 days after sowing (DAS) by using cono weeder, spraying 2, 4-D 1.0 kg/ha, and metsulfuron- methyl 5.0 g/ha. Two levels of N (100 and 75% of recommended dose of 90 kg N/ha) were superimposed. Rice alone with 5 t/ha FYM and recommended dose of 90-45-45 kg N-P-K/ha was taken as control.Concurrent growing of dhaincha and its incorporation at 30 DAS resulted in a weed suppression of 70% with an yield enhancement to the tune of 0.840 t/ha and increased profitability of ₹ 12520/ha). Application of 2,4-D resulted in maximum reduction of weeds without any adverse effect on rice. Nitrogen at different levels had no significant influence of weed incidence.