ASSESSMENT OF NUTRIENT MANAGEMENT TECHNOLOGIES FOR EGGPLANT PRODUCTION UNDER SUBTROPICAL CONDITIONS: A COMPREHENSIVE APPROACH

Abstract

SUMMARYWe developed a protocol for comprehensive evaluation of nutrient management (NM) technologies for production of eggplant taking its yield, produce quality, profitability, energy balance and environmental sustainability in terms of upkeeping soil quality as the goal variables. Fifteen NM technologies comprising of three sources of nutrients viz., organics [vermicompost (VC), farmyard manure (FYM) and mustard oil cake (MOC)], inorganic fertilizations [recommended N–P–K at the rate of 100–22–42 kg ha−1and 150% of recommended N–P–K (NPK^)] and their selected combinations were tested for growing the plants. Integrated NM technology was proved to be socio-economically sound and environment-friendly practice. It helped to upkeep soil quality by improving soil organic carbon stock, microbial biomass carbon, bulk density and available nutrients in soils. Combining all the parameters by employing non-parametric evaluation of regression factor scores through principal component analysis, the NM technology of VC3 Mg ha−1+NPK^ was found to be the best when considering the marketable fruits (12.27 Mg ha−1), economic return (benefit-cost ratio 3.3; marginal rate of return 8.7), energy conserving efficiency (net energy 113.8 GJ ha−1), soil and crop quality for human welfare. Only organics were less productive and profitable, and energetically less efficient than the integrated and inorganic NM systems and as such may not be sustainable for eggplant production in subtropical India.