Isolation and Characterization of Phosphate Solubilizing Bacteria from the Rhizosphere of Potato Plant

Abstract

Phosphorus is important for early shoot and root development, providing energy for plant processes such as ion uptake and transport. Phosphorus is the most important nutrient element (after nitrogen) limiting agricultural production in most regions of the world. Phosphorous is the second major nutrient for the plants, however, it is the least soluble in soil. The total phosphorous in the soil ranges from 0.01 - 0.2 per cent but only a small amount of it is available to the plants. In the present study, a total of ten different bacterial isolates were obtained from potato rhizosphere soil collected from different locations. Out of these, Enterobacter cancerogenus D-m-2, having potential to solubilize insoluble inorganic phosphate was characterized. The strains showed diverse levels of phosphate solubilization activity in liquid broth culture in presence of various carbon and nitrogen sources. Enterobacter cancerogenus D-m-2 showed maximum phosphate solubilizing with lactose as carbon source and ammonium oxalate as nitrogen source. The final value of in vitro Phosphate solubilization by the isolate was 8.37 μg/ml.