Abstract:
The present study assessed the effect of application of inorganic soluble phosphate (P) on phosphatase
enzyme activity of phosphate solubilizing bacterial strain identified as Pantoea agglomerans. The strain
was employed in phosphatase enzyme induction studies using N B R 1 P medium which contained Ca3(P04)2
as a source of inorganic insoluble P. The medium was amended with four levels of inorganic soluble P (0,
0.5, 1.0 and 1.5 g/1 K H 2 P O 4 viz., Po, Pi, P2 and P 3 ). As revealed by the results, phosphatase activity and
phosphate solubilization were decreased by inorganic soluble P ( K H 2 P O 4 ) in the N B R I P medium
inoculated with phosphate solubilizing bacterial strain. The highest phosphatase activity (118.85 U/ml)
and phosphate solubilization (642 pg/ml) were recorded when medium contained only inorganic
insoluble P and the lowest phosphatase activity (95.3 U/ml) and phosphate solubilization (210 pg/ml)
were recorded at the highest level of inorganic soluble P (1.5 g/1). Therefore it can be concluded that
presence of soluble P represses the P solubilization activity of P. agglomerans under in vitro conditions
