Department of Soil Science, Himachal Pradesh Krishi Vishvavidyalaya, Palampur, Himachal Pradesh, 176062.
* Present address: Potash & Phosphate Institute of Canada India Programme, Gurgaon, Haryana, 122001.
In a greenhouse experiment, soybean responded markedly, to Udaipur rock, phosphate (URP) on an acid soil (Hapludall). The mixture of single superphosphate (SSP) and URP in the ratio of 60:40 and 50:50 were effective regarding yield, etc. and interactions between mixtures and levels of P were not significant. Al-P and Fe-P fractions were significantly correlated with the dry matter yield of soybe,an a1kt P uptake. However, Al-P contributed maximum to plant utilizable P (Olsen's P).
Acid Alfisol, Udaipur rock phosphate, P uptake, AI-P
