Optimizing NPKS dosages for better morphological and yield traits of onion (Allium cepa) in rabi season in Jharkhand

The experiment was conducted to evaluate the impact of varying NPKS dosages on morphological characteristics, quality and yield of onion (Allium cepa L.) cv. Pusa Madhavi during rabi season of 2024–2025 under agroclimatic conditions of Hazaribagh, Jharkhand. Randomized block design with nine treatments with variable dosages of NPKS, replicated six times was used. Analysis of variance revealed significant differences across treatment combinations. Application of N:P:K:S @ 140:112:112:56 kg/ha (T₅) recorded the maximum number of leaves and plant height \60 days after transplanting, number of scales/ bulb, total soluble solids and neck thickness of the bulbs at harvesting. The treatment also produced the maximum weight for ten bulbs which was found statistically at par with application of N:P:K:S @ 130:104:104:52 kg/ha (T₄). Moreover, highest total yield/ plot was recorded in T₄, followed by T₅, while the lowest yield was observed in T₉. The increasing levels of NPKS dosages promotes vegetative growth and bulb weight. However, T₄ resulted in the highest yield/ plot with a comparatively lower fertilizer dosage than T₅, making it potentially superior for maximizing growth and productivity of onion in Jharkhand.