Effect of rice (Oryza sativa) straw management on growth and yield of wheat (Triticum aestivum)

A field experiment was conducted at Jorhat, Assam during 2004–05 and 2005–06 to find out an effective practice of rice (Oryza sativa L.) straw management in wheat (Triticum aestivum L. emend. Fiori & Paol.) as a component of integrated nutrient management. Straw was incorporated @ 5 t/ha with different decomposers, viz. starter N (one-third recommended dose of N), cellulose-decomposing microorganisms (CDM), earthworms culture (EC), EC + FYM, CDM + EC, FYM and starter N + CDM + EC + lime. These decomposers significantly improved the yield and yield components in wheat compared with straw removal. Incorporation of rice straw @ 5 t/ha under dual inoculation of cellulose-decomposing microorganisms and earthworms improved the grain yield by 2.46 t/ha. These also increased the nutrient uptake, available N, P, K in soil at harvest and benefit: cost ratio. Straw incorporation increased the organic C in the soil by 2–11% compared with straw removal. It also increased the microbial population in soil substantially irrespective of the decomposer used. Inoculation with CDM led to build-up of microbial population in the soil. Thus, rice straw incorporation with cellulose decomposing micro-organisms and earthworms resulted in higher yield, increased nutrient uptake, improved residual soil fertility and soil microorganism status and ultimately higher benefit: cost ratio of wheat.