Phosphorus absorption kinetics of some phosphate solubilizing bacterial strains isolated from river Ganga S cience

In this study, a total of twenty four phosphate solubilizing bacterial (PSB) colonies were isolated on the Pikovskaya’s agar medium from different effluent exposed sediment of river Ganga. The bacteria showing clear halo zones around their colonies were considered as phosphate solubilizers. Out of 24 phosphate solubilizing bacterial isolates, 4 potential isolates showing highest halo zone on Pikovskaya’s agar medium were selected for the phosphorus absorption kinetics study. Isolates RPSB6, SPSB13, JPSB16 and TPSB23 belong to genera Pseudomonas, Enterobacter, Bacillus and Flavobacterium respectively as identified by their physiological, morphological and biochemical characteristics. Among these 4 PSB isolates, Bacillus sp JPSB16 showed the maximum P absorption (Vmax) value of 72.4 (10 mg d number) followed by Flavobacterium sp TPSB23 (65.1), Enterobacter sp SPSB13 (62.2) and Pseudomonas sp RPSB6 (58.7), as compared to 26.3 (10 mg d number) for the average sediment microorganisms.