Relative Agronomic Efficiency of Udaipur Rock Phosphate on an Acid Inceptisol

Relative efficiency of Udaipur rock phosphate (URP), superphosphate, (SP) and their mixture in 1: 1 proportion was studied on an acid Inceptisol, at Jorhat. Mixture of superphosphate and Udaipur rock phosphate in 1: 1 ratio recorded the highest grain yield, P uptake, P recovery and available P in soil and was at par with superphosphate. Irrespective of sources, rice responded up to 38.7 kg P ha−1.