Influence of Spacing and Fertigation Levels on Growth and Yield of Onion (Allium cepa L.) cv. Agrifound Light Red under Semi-arid Conditions of Rajasthan, India

A field experiment was conducted during the rabi season 2025–2026 at the Horticultural Research Farm, School of Agricultural Sciences, Nirwan University, Jaipur, Rajasthan, to evaluate the influence of plant spacing and fertigation levels on the growth and yield of onion (Allium cepa L.) cv. Agrifound Light Red under semi-arid conditions. The experiment was laid out in a Factorial Randomized Block Design with three replications, comprising three spacings (15 × 10, 20 × 10 and 20 × 15 cm), three fertigation levels (75, 100 and 125% RDF) and a conventional soil-applied fertilizer control. The recommended fertilizer dose was 100:50:80 kg N:P₂O₅:K₂O ha⁻¹, with water-soluble fertilizers supplied through drip fertigation in split applications. The treatments significantly influenced crop growth, bulb development and yield. Among the treatment combinations, 20 × 10 cm spacing combined with 100% RDF through fertigation (T₅) performed best, producing superior vegetative growth, larger and heavier bulbs, higher marketable and total yields. The factor-wise response also indicated that 20 × 10 cm spacing and 100% RDF through fertigation were the most effective levels. The results indicate that appropriate plant population combined with balanced fertigation can improve resource utilisation and productivity of onion under semi-arid conditions. Thus, 20 × 10 cm spacing with 100% RDF through fertigation may be considered a promising production strategy for onion cv. Agrifound Light Red under the agro-climatic conditions of Rajasthan.