Soil microbe Bacillus subtilis (GB03) induces biomass accumulation and salt tolerance with lower sodium accumulation in wheat

Bacillus subtilis strain GB03 has been shown to confer salt tolerance in Arabidopsis thaliana. In this study, the potential for GB03 to promote biomass accumulation and increase salt tolerance was investigated in wheat (Triticum aestivum). Soil-grown wheat seedlings were assayed for dry-weight increase. Endogenous Na+ and K+ contents were determined in plants with or without soil inoculation with GB03 along with 0, 25 or 100 mM NaCl solution added to the soil. We demonstrated that the introduction of GB03 in the soil triggered wheat biomass accumulation. Furthermore, GB03 improved salt tolerance as measured by increased tissue mass, lower Na+ accumulation and improved K+/Na+ ratio when GB03-inoculated plants were grown under elevated salt conditions. This study provides insight for the application of selected bacteria to monocot crops to combat saline toxicity.