Positive Responses of Nitrogen-Fixing Bacteria Combined with Vermicompost on Farmland Heath and Peanut Yield

A study on the supplementation of Bacillus vireti combined with the vermicompost with two types of irrigation water [river water (RV) and underground water (UW)] on soil properties, growth, yield, and arsenic (As) accumulation of peanuts. The field study that was performed in Phuoc Hung, An Giang, Vietnam, consisted of three factors: (1) two vermicompost rates (0.0 and 10 t/ha); two inoculated methods of Bacillus vireti (supplementation and no supplementation); (3) two irigation water types (RW and UW) and four replications. The novel findings of this study include (i) a significant increase in fresh peanut yield, ranging from 11.0% to 23.4%, when 10 t vermicompost /ha was applied in combination with Bacillus vireti and non-As contaminated irrigation water (RW) compared to the control; (ii) a significant reduction in As accumulation in both stems (9.96% to 39.2%) and seeds (12.9% to 30.2%) due to the positive effects of Bacillus vireti. These results suggest that Bacillus vireti species has the potential to enhance soil fertility, peanut yield, and reduce As accumulation in peanuts when combined with vermicompost application. Moreover, this is a promising nitrogen-fixing microorganism for the production of organic microbial fertilizers to enhance soil health and crop productivity in the future. Keywords: Animal manure, deep well water, endophytic bacteria, groundnut, soil nutririon, supplementation.