Effect of NPK Conjunction with City Waste Compost on Yield & Economics of Green Gram (Vigna radiata L.)

Abstract

Green gram productivity and soil health can be improved through integrated nutrient management using balanced NPK fertilisers along with city waste compost, which together enhance growth, yield, nutrient uptake, and long-term soil fertility while reducing the drawbacks of sole chemical fertiliser use. A field experiment was undertaken during the Zaid seasons of 2023 and 2024 at the research farm of the Department of Soil Science and Agricultural Chemistry, Sam Higginbottom University of Agriculture, Technology and Sciences (SHUATS), Prayagraj, Uttar Pradesh, to assess the influence of combined NPK fertilisation and city waste compost (CWC) on the growth and yield of green gram (*Vigna radiata* L.). The study was arranged in a factorial randomised block design comprising sixteen treatment combinations, involving four levels of NPK (0, 50, 75 and 100%) and four levels of CWC (0, 3, 6 and 9 t ha⁻¹), each replicated three times. The experimental soil was sandy loam in texture, slightly acidic to neutral in reaction, and characterised by low organic carbon and available nitrogen, with medium levels of available phosphorus and potassium. The results revealed that application of 100% NPK along with city waste compost @ 9 t ha-1 (T16) recorded the highest seed yield (18.71 and 21.82 q ha-1), stover yield (23.29 and 24.62 q ha-1), gross return (₹154339.46 and ₹179464.48 ha-1), and net return (₹92568.26 and ₹117693.27 ha-1) during 2023 and 2024, respectively. The pooled data also confirmed the superiority of T16 with maximum seed yield (20.22 q ha-1), stover yield (23.96 q ha-1), gross return (₹166901.97 ha-1), and net return (₹105130.77 ha-1). However, the highest pooled B: C ratio (2.27) was recorded under treatment T13 (100% NPK + city waste compost 0 t ha-1). The improvement in yield and economics due to integrated nutrient management may be attributed to balanced nutrient supply, improved soil fertility, enhanced nutrient uptake, and better crop growth resulting from the combined application of inorganic fertilisers and organic compost. The study concluded that the conjoint use of 100% NPK with city waste compost @ 9 t ha-1 proved most effective for maximising productivity and economic returns of green gram under the prevailing agro-climatic conditions. The findings also highlight the importance of city waste compost as a sustainable organic amendment for improving soil health and green gram productivity under the Agro-climatic conditions of Prayagraj.