Effect of N application with and without PK on potato yield in red soils

Studies were carried out in red sandy loams, with low content of organic carbon and available phosphorus but high content of potash, to study the yield responses of potato, cv. Kufri Chandramukhi, to varying levels of N, P and K under irrigated conditions (Rabi, 1975–76 and 1976–77). A combination of N at 180 kg/ha and both P and K at 50 kg/ha recorded the maximum yield (222.2 q/ha) compared to other combinations. The results indicated favourable responses to fairly high N levels (120–180 kg/ha) and moderate levels of P (50 kg/ha) irrespective of K levels. N₃ P₁ K₁ combination (180 kg, 50 kg and 50 kg per hectare respectively) increased the yield by 115.1 q/ha over the control (No Po Ko).