Influence of Nitrogen, Phosphorus, Potassium and Planting Distance on the Maturity and Yield of Onion (Allium Cepa L.).

The experiment was conducted to find out the optimum spacing and N, P and K requirements for onion crop variety Punjab Selection at the Vegetable Experimental Farm, Punjab Agricultural University, Ludhiana during 1971–72. It was observed that the plants took maximum number of days (131.60) to mature under the influence of N₁₅₀ kg/ha as compared to N₇₅ kg/ha and control which were at par among themselves. Closer spacing of 15 x 10 cm produced maximum number of bulbs and total bulb yield (116.96 q/ha) than wider spacings. The yield was also increased with an increase in the doses of nitrogen. The application of N 150 kg and 75 kg/ha being at par with each other gave highest bulb yield of 127.88 and 114.66 q/ha respectively. The effect of phosphorus, potash and various interactions of N, P and K with different spacings was non-significant in increasing the yield.