Salt Tolerance Mechanism and Species Identification of the Plant Rhizosphere Bacterium JYZ-SD2.

Abstract

A salt-tolerant microbe strain JYZ-SD2 was investigated to develop biological soil amendments to stimulate salix growth and acclimation in costal salt-affected soils. The salt tolerance mechanism of strain JYZ-SD2 was investigated by detecting the salt-tolerant growth characteristics, biofilm formation, ion distribution, secondary metabolites, and zymogram profiling. The strain was identified by physiological and biochemical characteristics (Biolog), 16S rDNA sequencing, and cry1/7/9 gene expressing. With increasing of NaCl concentration, strain JYZ-SD2 adapted to the increased osmotic pressure by prolonging the retardation period, slowing down the growth rate of the logarithmic phase, increasing spo0A gene expression, increasing biofilm formation, reducing Na+ uptake, and changing the expression of metabolites and intracellular soluble proteins. The results showed that strain JYZ-SD2 could be assigned to Bacillus cereus.