Effect of pH and Carbon Source on Phosphate Solubilization by Bacterial Strains in Pikovskaya Medium.

Phosphate-solubilizing bacteria (PSB) transform precipitated inorganic phosphorus into soluble orthophosphates. This study evaluated the efficiency of tricalcium and iron phosphate solubilization in Pikovskaya medium using five bacterial strains (A1, A2, A3, A5, and A6) cultured in acidic and alkaline pH levels. The bacterial strain that proved to be more efficient for P solubilization and was tolerant to pH variations was selected for assessing bacterial growth and P solubilization with glucose and sucrose in the culture medium. The bacterial strains were identified through 16S rRNA gene sequencing as A1, (A2), (A3), (A5), and (A6). These five bacterial strains grew, tolerated pH changes, and solubilized inorganic phosphorus. The bacterial strain A3 solubilized FePO (4 mg L) and Ca(PO) (50 mg L). P solubilization was assayed with glucose and sucrose as carbon sources for A3 ( MN100586). After four culture days, Ca(PO) was solubilized, reaching 246 mg L with sucrose in culture media. Using glucose as a carbon source, FePO was solubilized and reached 282 mg L in six culture days. Our findings were: , and as new bacteria, can be reported as P solubilizers with tolerance to acidic or alkaline pH levels. The bacterial strain grew using two sources of inorganic phosphorus and carbon, and it tolerated pH changes. For that reason, it is an ideal candidate for inorganic phosphorus solubilization and future production as a biofertilizer.