Best Viewed in Mozilla Firefox, Google Chrome

Phosphate solubilizing microorganisms

PrintPrintSend to friendSend to friend
  •  Phosphorus is the second important nutrient after nitrogen for plants and microorganisms. 
  • Further, there is build up of insoluble phosphates in soil where phosphatic fertilizers have been applied over long periods.  
  • Some heterotrophic bacteria and fungi are known to have the ability to solubilize inorganic P from insoluble sources. 
  • Important phosphate solubilizing organisms are Pseudomonas striata, Bacillus polymyxa, Aspergillus awamori and Penicillium digitatum etc. P solubilizing fungal population is generally found more in acid to neutral soils while the bacterial population in neutral to alkaline soils. 
  • Their microorganisms can grow on insoluble phosphatic sources such as tricalcium phosphate, ferric, aluminium and magnesium phosphate, rock phosphate and bone meal and convert them into soluble forms. 
  • These organisms secrete various organic and inorganic acids. 
  • They act on insoluble phosphates and convert them into soluble phosphates in the rhizosphere. 
  • Among the microorganisms, bacteria are found to be more efficient in the secretion of organic acids. 
  • Addition of organic manures helps in increasing the solubilizing power of the microorganisms. 
  • PSB are reported to facilitate P supply to plant by solubilising insoluble P and results in better P uptake following their inoculation (Rautela et al., 2001).
  • The utilization of native soil phosphorus is mostly unavailable to crops due to low solubility. 
File Courtesy: 
R K Avasthe, Subhash Babu and Raghavendra Singh ICAR Research Complex for NEH Region
Copy rights | Disclaimer | RKMP Policies