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

Abstract

Green gram (Vigna radiata L.) is an important pulse crop whose productivity is often limited by declining soil fertility, making integrated nutrient management using chemical fertilizers, organic amendments, and compost essential for sustaining yield and soil health. A field experiment was conducted 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 evaluate the effect of NPK fertilization conjugated with city waste compost (CWC) on the growth and yield of green gram (Vigna radiata L.). The experiment was laid out in a factorial randomized block design with sixteen treatment combinations comprising four levels of NPK (0, 50, 75 and 100%) and four levels of CWC (0, 3, 6 and 9 t ha-1), replicated thrice. The experimental soil was sandy loam, slightly acidic to neutral in reaction, low in organic carbon and available nitrogen, and medium in available phosphorus and potassium. The results revealed that increasing levels of NPK significantly improved growth and yield parameters of green gram. Application of 100% NPK recorded the highest seed yield of 16.05 and 18.43 q ha-1 during 2023 and 2024, respectively, with a pooled mean of 17.22 q ha-1, compared to the lowest yields under control. Similarly, application of CWC at 9 t ha-1 significantly enhanced plant growth, dry matter accumulation and yield, producing a pooled seed yield of 14.42 q ha-1. The interaction effect was significant, and the combined application of 100% NPK + 9 t ha-1 CWC produced the maximum seed yield (18.71 and 21.82 q ha-1 during 2023 and 2024, respectively; pooled mean 20.22 q ha-1), along with the highest biological yield. The study concluded that integrated application of recommended NPK with 9 t ha-1 city waste compost is an effective and sustainable nutrient management strategy for enhancing productivity of green gram under the agro-climatic conditions of Prayagraj.