Effect of Rice Straw Management Practices on Yield of Kharif Rice and Soil fertility under Rice-Rice Cropping System

Field experiments were conducted during kharif seasons of 2004 and 2005 to evaluate the influence of different rice straw management practices on rice productivity, nutrient uptake and soil health. Straw was incorporated @ 5 t ha⁻¹ with different decomposers viz., starter N (1/3 recommended dose of N), cellulose decomposing microorganisms (CDM), earthworm culture (EW), EW + farmyard manure (FYM), CDM+ EW, FYM and starter N + CDM + EW + lime along with a control (without straw incorporation). Significant improvement in rice productivity was observed with straw incorporation over control. The highest grain yield was recorded when straw was incorporated with CDM and earthworms and was comparable to the treatment where straw was incorporated with CDM alone. These treatments also significantly increased the nutrient (N, P and K) uptake and residual soil fertility. Soil organic carbon and microbial population in soil were increased substantially due to straw incorporation, irrespective of the decomposer used. The microbial population in soil was highest under the treatment receiving straw incorporation with CDM and earthworms.