Skip to main content
Log in

Solubilization of rock phosphates byRhizobium andBradyrhizobium

  • Papers
  • Published:
Folia Microbiologica Aims and scope Submit manuscript


The ability ofRhizobium andBradyrhizobium strains to solubilize phosphate from hydroxyapatite was determined in a medium containing NH4Cl or KNO3. The presence of NH4 + in the medium resulted in higher solubilization of phosphate as compared to the presence of KNO3, with the exception ofR. leguminosarium bv. viceae strain TAL 1236 and 1402 which solubilized comparable amounts of phosphate in a medium containing either KNO3 or NH4Cl. These results suggest that the strains employ two different mechanisms for phosphate solubilization, one depending on the presence of NH4 +, the other not requiring its presence. Temperature and aeration (O2 demand) optima were 30°C and 4.2 Hz (shaking frequency), respectively. In nonsterile soil the tested strain (R. meliloti TAL 1236) was very effective in solubilizing rock phosphate.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or Ebook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others


  • Asea P.E.A., Kucey R.M.N., Stewart J.W.B.: Inorganic phosphate solubilization by twopenicillium species in solution culture and soil.Soil Biol. Biochem.20, 459–464 (1988).

    Article  CAS  Google Scholar 

  • Banenko YU. S., Tyrygina G.I., Grigor'ev E.F., Dohgikh L.M., Borisow T.I.: Biological activity and physiological-biochemical properties of phosphate dissolving bacteria.Microbiologiya53, 533–539 (1984).

    Google Scholar 

  • Beever R.E., Burns D.G.W.: Phosphorus uptake, storage and utilization by fungi.Adv. Bot. Res.8, 127–129 (1980).

    Article  CAS  Google Scholar 

  • Chen P.S., Toribara T.Y., Warner H.: Microdetermination of phosphorus.Analyt. Chem.28, 1756–1758 (1956).

    Article  CAS  Google Scholar 

  • Cabala-Rosand P., Wild A.: Direct use of low grade phosphate rock from Brazil as fertilizer. II. Effect of mycorrhizal inoculation and nitrogen source.Plant & Soil65, 363–373 (1982).

    Article  CAS  Google Scholar 

  • Halvorson H.O., Keynan A., Kornberg H.L.: Utilization of calcium phosphates for microbial growth at alkaline pH.Soil Biol. Biochem.22, 887–890 (1990).

    Article  CAS  Google Scholar 

  • Kucey R.M.N.: Phosphate-solubilizing bacteria and fungi in various cultivated and virgin Alberta soils.Can. J. Soil. Sci.63, 671–678 (1983).

    Article  CAS  Google Scholar 

  • Leyval C., Barthelin J.: Interactions betweenLaccaria laccata, Agrobacterium radiobacter and beech roots: Influence on P, K, Mg and Fe mobilization from mineral and plant growth.Plant & Soil117, 103–110 (1989).

    Article  CAS  Google Scholar 

  • Roos W., Luckner M.: Relation between proton extrusion and fluxes of ammonium ions and organic acid inPenicillium cyclopium.J. Gen. Microbiol.130, 1007–1014 (1984).

    CAS  Google Scholar 

  • Thomas G.V.: Occurrence and ability of phosphate-solubilizing fungi from cocconut plant soils.Plant & Soil87, 357–364 (1985).

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations


Rights and permissions

Reprints and permissions

About this article

Cite this article

Abd-Alla, M.H. Solubilization of rock phosphates byRhizobium andBradyrhizobium . Folia Microbiol 39, 53–56 (1994).

Download citation

  • Received:

  • Revised:

  • Issue Date:

  • DOI: