Relative Efficacy of Different Organic Materials and Inorganic Sources of Nitrogen on Yield Attributes in Maize-Mustard Cropping System

A field experiment was conducted at the Regional Agricultural Research Station, Polasa, Telangana, India during kharif (2018 and 2019) and rabi (2018-19 and 2019-20) seasons to evaluate integrated nutrient management (INM) practices on maize yield and their residual effect on mustard in a maize-mustard cropping system. Maize was treated with nine nutrient management treatments including 100% recommended dose of fertilizer (RDF), 75% recommended dose of nitrogen (RDN) combined with various organic sources (FYM, vermicompost, poultry manure, sheep manure, neem cake), and biofertilizers (Azotobacter, Azospirillum). Mustard received four fertilizer levels (0%, 50%, 75%, and 100% RDF) as residual treatments. Maize treated with 75% RDN + 25% N through vermicompost produced the longest cobs, greatest cob girth, and highest kernel number, resulting in grain yields of 6349 and 6514 kg ha^-1 in 2018 and 2019, respectively. It outperformed several treatments and was comparable to 100% RDF and FYM treatments. In the rabi season, mustard seed yield was highest with residual 75% RDN + 25% N through FYM (1174 and 1266 kg ha^-1) and was on par with poultry manure, neem cake, and vermicompost residuals, all significantly superior to sheep manure, biofertilizers, and 100% RDF, which recorded the lowest yields. Among fertilizer levels, 100% RDF significantly increased mustard yield (1260 and 1334 kg ha^-1), comparable to 75% RDF. These results indicate that combining 75% chemical nitrogen with organic amendments, particularly vermicompost and FYM, enhances maize productivity and sustains mustard yield, supporting sustainable nutrient management in maize-mustard cropping systems.