World Journal of Microbiology and Biotechnology

, Volume 14, Issue 5, pp 669–673 | Cite as

Effect of buffering on the phosphate-solubilizing ability of microorganisms

  • P. Gyaneshwar
  • G. Naresh Kumar
  • L.J. Parekh


Native microflora present in the alkaline vertisols and two phosphate-solubilizing bacteria (PSB) isolated from soil using conventional screening media could not release phosphorus from alkaline Indian vertisol soils supplemented with carbon and nitrogen sources. The two PSBs could solubilize both rock phosphate and di-calcium phosphate in unbuffered media but failed to solubilize rock phosphate in buffered media. The organic acids secreted by these PSBs were 20–50 times less than that required to solubilize phosphorus from alkaline soil.

Organic acids and phosphate solubilizing microorganisms phosphate solubilization 


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Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • P. Gyaneshwar
    • 1
  • G. Naresh Kumar
    • 2
  • L.J. Parekh
    • 2
  1. 1.Centre for Genetic EngineeringIndian Institute of ScienceBangalore-India
  2. 2.Department of Biochemistry, Faculty of ScienceM.S. University of BarodaVadodaraIndia

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