It is an important trait in plant growth-promoting bacteria the ability to solubilize and mineralize insoluble inorganic phosphate compounds, making the element available for plants. High populations of phosphate solubilizing bacteria (PSB) will increases the P uptake by plants and reduce the application of organic fertilizers. In this study, a total of 14 PSB isolates from rhizosphere of maize, cotton, ragi, rice, turmeric, sugarcane, cowpea and green gram were tested for the mineral phosphate solubilizing (MPS) activities in Hydroxy Apatite (HAP) broth by analyzing the soluble-P content after 72 h of incubation at 30oC. The ‘P’ solubilising ability of SGN 1 was found to be 35.56 mg/100ml isolated from sugarcane rhizosphere soil. SGN 1 which was showing higher phosphate solubilizing ability in HAP broth was selected for molecular characterization with amplifying and sequencing of 1.3 kb 16S rRNA gene. Based on the BLASTn homology it was found that PSB sugarcane isolate SGN1 having 95% identity with showed 99% homology with Burkholderia thailandensis.
Isolation, Burkholderia thailandensis, Phosphate solubilizing, Rhizosphere
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