Ecology, Environment and Conservation Paper

POTENTIAL OF RHIZOSPHERE MICROORGANISMS IN PHOSPHATE SOLUBIZATION

P. Srilatha and K. Venkateswarlu

Abstract

The diversity of phosphate-solubilizing microorganisms in rhizhosphere soils of groundnut (Arachis hypogaea L.) and foxtail millet (Setaria italica (L.) Beauv.) was studied in pot experiments. Out of 23 phosphate-solubilizing microorganisms isolated from the rhizosphere, only the species of Bacillus and Aspergillus were found to be the most prevalent in the rhizosphere. The isolates which exhibited good solubilization of tricalcium phosphate in solid medium were further used for their phosphate solubihzation in liquid medium. Surprisingly, the potential of some cultures for phosphate solubilization decreased. Aspergillus spp. proved to be potent phosphate solubilizers than the species of Bacillus. Pikovskaya's medium was an efficient medium compared to the phosphate growth medium, recommended by National Botanical Research Institute of Lucknow or mineral salts medium.