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 prac- tice of rice (Oryza sativa L.) straw management in wheat (Triticum aestivum L. emend. Fiori & Paol.) as a compo- nent of integrated nutrient management. Straw was incorporated @ 5 tlha 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 Vha under dual in- oculation of cellulose-decomposing microorganisms and earthworms improved the grain yield by 2.46 Vha. 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 2-1 1% compared with straw removal. It also increased the microbial popula- tion 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.