Influence of Nitrogen Management on Rice Equivalent Yield and Soil Properties in Rice-Wheat Cropping System in Calcareous Soil of Bihar

This paper aims to explore the issues related to exploitation of soil fertility caused by injudicious application of sole chemical fertilizer. Restoring the soil fertility in the farming system is vital to sustain crop productivity. In this context, considerable attention has been given to the different sources of organic manure. A two-year field experiment was carried out to evaluate the influence of nitrogen management through organic sources on rice and wheat productivity along with soil health under rice-wheat cropping system. Results observed that significantly maximum rice equivalent yield (103.23 q ha-1), gross returns (₹1,86,347 ha-1) and net returns (₹ 1,13424 ha-1) were recorded in treatment with mycostraw @ 50% RDN (recommended dose of nitrogen) + green manure. Application of mycostraw @ 75% RDN (recommended dose of nitrogen) + green manure recorded significantly higher value of water holding capacity (31.39%), soil organic carbon (0.47%), available nitrogen (240.68 kg ha-1), available phosphorus (27.43 kg ha-1) and available potassium (156.10 kg ha-1) and also achieved higher value of soil microbial biomass carbon (289.55 mg kg-1 soil), bacterial population (5.06 ×107 cfu g-1 soil), fungal population (4.16 ×104 cfu g-1 soil) and actinomycetes population (2.57 ×107 cfu g-1 soil) with lower bulk density (1.365 g cm-3) in post-harvest soil as compared to other treatments. Therefore, the application of mycostraw @ 50% RDN + green manure along with 75% RDN is environmentally and economically feasible nutrient management approach for sustainable rice-wheat cropping system in the calcareous soil of Bihar.