Effect of Integrated Nutrient Management on Growth and Yield of Rabi Onion (Allium cepa L.) under Eastern Uttar Pradesh Conditions

Abstract

Onion (Allium cepa L.) is a globally important crop valued for its culinary, nutritional, and medicinal properties. Despite India being a major producer, productivity remains suboptimal, particularly during the Rrabi season. This study evaluated the effect of integrated nutrient management (INM) involving organic manures and biofertilizers on the growth, yield, and nutrient uptake of Rabi onion over two consecutive rabi seasons (2019–2021) at Post Graduate College, Ghazipur, Uttar Pradesh. The experiment, laid out in a factorial randomized block design, assessed twelve treatment combinations of chemical fertilizers, farmyard manure (FYM), vermicompost, Azotobacter, and phosphate-solubilizing bacteria (PSB). Results revealed that treatment T8 (50% N from FYM + 50% N from fertilizers + 100% PK + Azotobacter) consistently outperformed others in terms of plant height, number of leaves, bulb size, shoot biomass, and overall yield (275.16 q/ha). INM treatments significantly improved physiological and yield parameters, with organic and microbial inputs enhancing soil fertility and nutrient efficiency. The findings highlight the agronomic and environmental benefits of integrating organic and biofertilizer-based nutrient sources for sustainable onion cultivation, particularly under semi-arid conditions.