Standardization of suitable fertilizer doses of kharif onion for calcareous soils

An experiment was conducted at Muraul farm of Tirhut College of Agriculture, Dholi, Muzaffarpur, (Rajendra Agricultural University, Pusa, Bihar), during Kharif season of 2010–11 and 2011–12 to find out suitable fertilizer doses of nitrogen, potash and sulphur for kharif onion variety Agrifound dark red under calcareous soil of North Bihar. In the present investigation maximum plant height (59.55 cm) and no. of leaves/plant (10.64) were recorded with highest level of nitrogen i.e., 150 kg/ha, while maximum marketable yield (265.54 q/ha) and total yield (272.89 q/ha) was recorded with 125 kg N/ha. In case of potash maximum plant height (56.06 cm), no of leaves/plant (9.46), marketable yield (230.87 q/ha) and total yield (238.73 q/ha) were recorded with application of 100 kg/ha. Sulphur also showed the maximum plant height (55.52 cm), no. of leaves/plant (9.59), marketable yield (234.49 q/ha) and total yield 242.69 q/ha with highest level of 40 kg/ha. Among various fertilizer combinations the maximum plant height (62.76 cm), no. of leaves per plant (12.60), marketable yield (295.11 q/ha) and total yield 298.72 q/ha were recorded with treatment combination 125 kg nitrogen + 80 kg phosphorus + 100 kg potash + 40 kg sulphur per hectare.