Management of rice residues for rice production – A review

After the harvest of rice, the residues are left in the field usually in the form of stubbles and roots. Rice crop residues serves as a source of soil organic matter which releases the plant nutrients to the soil for its enrichment. Rice crop residues obtained from one ha area in one season could substitute about 30.5 kg N, 3.5 kg P₂O₅ and 14 kg K₂O besides appreciable quantities of secondary and micro nutrients. It also changes the soil reaction in the favourable manner for crop production by altering the CEC, CO₂ content and humus besides improvement in structure. Straw incorporation provides an opportunity for replenishing the soil nutrients as against burning the residues which creates atmospheric pollution and loss of valuable nutrients in the form of volatilization. This being the case, rice straw contributing for the sustainable agriculture needs proper conservation and utilization in the context of reducing fertilizer subsidy and raising fertilizer import bill. Hence the references pertaining to the estimation of rice crop residue availability, riutrient composition, decomposition pattern, effect of straw incorporation on soil fertility and crop growth are reviewed in this paper for strengthening the future research.