Saline soils reduce available phosphorus, retarding plant growth, and rice is particularly affected. We evaluated
the ability of purple nonsulfur bacteria to resist the acidic-sodium conditions in saline acid sulfate soil and saline
soil, and their ability to enhance rice growth and grain yield by releasing normally unavailable phosphorus. Two
P-solubilizing Luteovulum sphaeroides strains were applied to rice seedlings in a soil pot experiment. Single cultures
and a mixed (1:1) culture of the strains increased rice growth and grain yield up to 10% in saline acid
sulfate soil and 18% in saline soil. After harvest, both inoculated soils showed significantly increased pHH2O but
significantly decreased electrical conductivity. The increase in Pavail in both inoculated soils resulted in higher
accumulations of P in the rice plants. The need for chemical P fertilizer was reduced by 50% of the recommended
application. Both inoculated soil types showed significant increases in NH4+ and potassium. Sodium concentrations
in both inoculated soil types were significantly lower than in controls. Proline content in rice from both
inoculated soil types was also significantly lower. Rice grain yields were proportional to the inoculated bacterial
populations.