Influence of purple non-sulfur bacterial augmentation on soil nutrient dynamics and rice () growth in acidic saline-stressed environments.

The aim of the current study was to assess the potency of the exopolymeric substances (EPS)-secreting purple non-sulfur bacteria (PNSB) on rice plants on acidic salt-affected soil under greenhouse conditions. A two-factor experiment was conducted following a completely randomized block design. The first factor was the salinity of the irrigation, and the other factor was the application of the EPS producing PNSB ( EPS18, EPS37, and EPS54), with four replicates. The result illustrated that irrigation of salt water at 3-4‰ resulted in an increase in the Na accumulation in soil, resulting in a lower rice grain yield by 12.9-22.2% in comparison with the 0‰ salinity case. Supplying the mixture of EPS18, EPS37, and EPS54 increased pH by 0.13, NH by 2.30 mg NH kg, and available P by 8.80 mg P kg, and decreased Na by 0.348 meq Na 100 g, resulting in improvements in N, P, and K uptake and reductions in Na uptake, in comparison with the treatment without bacteria. Thus, the treatments supplied with the mixture of EPS18, EPS37, and EPS54 resulted in greater yield by 27.7% than the control treatment.