PHOSPHORUS AVAILABILITY FROM ROCK PHOSPHATE AS INFLUENCED BY SULPHUR AND BIOFERTILIZERS IN INCEPTISOL SOIL

Abstract

The results indicated that incubation of rockphosphate, along with elemental sulphur, PSB and EM culture showed a significant decrease in soil pH due to elemental sulphur @ 30 and 60 Kg ha-1 along with PSB and EM solution, alone or in combination. A significant decrease in the calcium carbonate content was also observed in these treatments. The results revealed highest available phosphorus content in the rock phosphate treatment + 60 kg S ha-1 + PSB + EM solution. The maximum alkaline phosphatase activity was observed in the rock phosphate treatment with PSB, EM solution and elemental sulphur at 30 days incubation stage. The results of both the experiments prove the utility of rock phosphate as an alternative source of phosphorus nutrition or soybean, when used along with 30 kg ha-1 elemental sulphur + PSB + EM solution and recommended dose of nitrogen.