Isolation and identification of microorganism’s resistant to soil salinization

Abstract

315 variants of halotolerant bacteria were isolated from soil samples taken around Starobin potash deposit mined by Belaruskali concern. Nitrogen-fixing isolate CA-6 and phosphate-solubilizing isolate Cp-1 capable to withstand abiotic stress caused by sodium chloride in concentration 1710 and 2565 mM, respectively and water deficiency characterized by osmotic potential -0.20 and -0.42 MPa were sorted out. Isolate Cp-1 may dissolve phosphates yielding halo zones 9 mm in diameter while isolate CA-6 displays nitrogenase activity 44.0 nM C2H2/vial/3 days. Both isolates are growth-promoting organisms, distinguished by the ability to synthesize IAA in concentrations 89.7 and 37.8 μg IAA/ml of cultural liquid, respectively. The selected salt-resistant isolates were identified based on analysis of the nucleotide sequence of the 16S rRNA gene and data of MALDI-TOF mass spectrometry and were referred to the species Rhodococcus jostii and Priestia megaterium. Halotolerant strains Priestia megaterium Cp-1 and Rhodococcus jostii CA-6 were deposited in Belarusian collection of non-pathogenic microorganisms under the respective registration numbers BIM B-1314D and BIM B-1353D.