ISOLATION AND EVALUATION OF SILICATE SOLUBILIZING BACTERIA FOR PLANT GROWTH PROMOTING TRAITSGOURAV CHOPRA, NANDNI, SAVITA RANI AND LEELA WATIAbstract Silicate solubilizing bacteria are known for their ability to dissolve silicates to monosilicic acid, a form of silica absorbed by plant roots. In the present study, 40 bacterial isolates (SSB1-SSB40) were retrieved from rhizospheric soil of paddy and garden soil on Bunt and Rovira medium. Silicate solubilization indices of the forty silicate solubilizing bacterial isolates varied from 1.09 to 2.66, six promising silicate solubilizer (SSB1-SSB6) were further evaluated for solubilization of phosphate, zinc and potassium; indole acetic acid and hydrocyanic acid production and ammonia excretion. Isolate SSB2 exhibited maximum solublization, indices for silicate (2.66) and potassium (3.33), while isolate SSB3 was efficient zinc and phosphate solubilizer. All six isolates were producing indole acetic acid (IAA) ranging from 5.72-12.40 ïg/ml. Highest IAA production (12.40 ïg/ml) and ammonia excretion (4.60 ïg/ml) was observed in isolate SSB2. Promising silicate solubilizing bacterial isolates with growth promoting traits could be further assessed as silicon biofertilizer in different crops. |