Effect of phosphate solubilizing bacteria on phosphorus release kinetic in rhizosphere of sugarcane and correlation with various source of phosphorus

The effect of sugarcane rhizospheric secretions and phosphate solubilizing bacteria on soil phosphorus desorption kinetic was examined at greenhouse conditions. The experiment was carried out with two treatments, including phosphorus levels (0% (blank, P0), 50% (P50) and 100% (P100) and phosphate solubilizing bacteria strains (Enterobacter cloacae R13 (R13) and Enterobacter cloacae R33 (R33). Soil sampling was conducted in 60, 95 and 140 days after planting. Statistical evaluation was performed as completely randomized factorial design with three replicates. The kinetics of phosphorus desorption was investigated by successive extraction method during 30 to 5760 min. According to results, high percentage of phosphorus fertilizer and phosphate solubilizing bacteria lead to increase of phosphorus desorption. Desorption kinetics was described by second order and power function equations well. Comparison of power function equation parameters among various treatments showed that the maximum coefficients were obtained at the lowest phosphorus fertilizer and phosphorus solubilizing bacteria. The reverse relationship was found between soil available phosphorus concentration and kinetic power function parameters, based on correlation analysis. Using of phosphorus solubilizing bacteria enhance the phosphorus bioavailability for plant.