Nutrient management in white onion (Allium cepa) and its effect on growth and yield

A field experiment was carried out during rabi season of 2021-2022 and 2022-2023 at Instructional Farm, Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth, College of Agriculture, Dapoli, Dist. Ratnagiri, Maharashtra, to study the nutrient management in white onion (Allium cepa) and its effect on growth and yield. The experiment was laid out in split plot design with twenty treatment combinations replicated thrice. The main plot consisted of four conventional fertilizer treatments: F₁ - control, F₂ - 100% RD of N and P + 100% RD of K, F₃-75% RD of N and P + 100% RD of K and F₄ - 50% RD of N and P + 100% RD of K, the sub-plot consisted of five nano-fertilizer treatments: N₁ - control, N2 - 25% RD of N through Nano-urea + 25% RD of P through Nano-phosphorous, N₃ - 50% RD of N through Nano-urea + 25% RD of P through Nano-phosphorous, N₄ - 25% RD of N through of Nano-urea + 50% RD of P through Nano-phosphorous and N5 - 50% RD of N through of Nano-urea + 50% RD of P through Nano-phosphorous. It was found that, the conventional fertilizer treatment F₂ (100% RD of N and P + 100% RD of K) and the nano fertilizer treatment N₃ (50% RD of N through nano-urea + 25% RD of P through nano-phosphorous) recorded significantly higher growth and yield in white onion. Further, the treatment combination F2N3 [100% RD of N and P + 100% RD of K and 50% RD of N through nano-urea + 25% RD of P through nano-phosphorous (2 sprays at 45 and 60 DAT)] recorded significantly higher number of functional leaves plant-1, bulb neck diameter, bulb fresh weight bulb-1 (g) and bulb yield (q ha^-1) in white onion.