ISOLATION AND CHARACTERIZATION OF ZINC SOLUBILIZING BACTERIA FROM STONE QUARRY DUST POWDER

D.N. VIDYASHREE¹, R. MUTHURAJU², P. PANNEERSELVAM³*, B. SARITHA⁴, A.N. GANESHAMURTHY^5
1Department of Agricultural Microbiology, University of Agricultural Sciences, Gandhi Krishi Vigyan Kendra, Bengaluru, 560 065, India
²Department of Agricultural Microbiology, University of Agricultural Sciences, Gandhi Krishi Vigyan Kendra, Bengaluru, 560 065, India
³ICAR-National Rice Research Institute, Cuttack, 753006, Odisha
⁴ICAR-Indian Institute of Horticultural Research, Hessaraghatta lake post, Bengaluru, 560089, Karnataka
⁵ICAR-Indian Institute of Horticultural Research, Hessaraghatta lake post, Bengaluru, 560089, Karnataka
* Corresponding Author : panneerccri@rediffmail.com

Received : 29-10-2016     Accepted : 07-11-2016     Published : 18-11-2016
Volume : 8     Issue : 56       Pages : 3078 - 3081
Int J Agr Sci 8.56 (2016):3078-3081

Keywords : Zinc solubilizing bacteria, Quarry powder, Zinc sources, Bacillus aryabhattai, Solubilization
Academic Editor : Prof P. J. George
Conflict of Interest : None declared
Acknowledgements/Funding : The authors gratefully thank the Director, Indian Council of Agricultural Research - Indian Institute of Horticultural Research for the support and infrastructure facilities.
Author Contribution : None declared

Substantial quantity of inorganic zinc applied to the soil is converted into unavailable form, but it can be converted back into available form to make it access to the plants by the intervention of zinc solubilizing bacteria. In this study, two zinc solubilizing bacteria were isolated from stone quarry dust powder, after purification and characterization, these isolates were identified as Bacillus aerophilus and Enterobacter sp by 16S rRNA gene sequencing. These two new isolates along with twenty two isolates including the reference strain of Bacillus aryabhattai obtained from microbiology lab, ICAR-IIHR, Bengaluru were then assessed for their ability of zinc solubilization in both solid and liquid basal media. The results indicated that among all isolates, B. aryabhattai showed significant increase in solubilization and produced larger clear halo zone on solid agar medium amended with 0.1% of zinc sources viz., zinc oxide (42.1 mm), zinc carbonate (46.3 mm) and zinc phosphate (26.7 mm). Similarly, in liquid basal medium containing 0.1% of zinc sources, B. aryabhattai enhanced solubilization significantly and released the higher amount of zinc with zinc oxide (554.8 ppm), zinc carbonate (368.6 ppm) and zinc phosphate (576.5 ppm) after 15 days of incubation as compared with other isolates. The pH of the culture broth was found to be decreased in the range of 3.33 to 3.35. Among all isolates, B. aryabhattai was found as the most promising zinc solubilizing bacteria; hence it can be exploited as potential bio-fertilizer for sustainable crop production.