Soybean growth Promotion and Phosphate Solubilization by bacillus Subtilis strains in Greenhouse

The aim of this work was to verify the Bacillus subtilis efficiency in soybean growth promotion, cultivated in soil with and without natural phosphate fertilization under greenhouse conditions. Seven Bacillus subtilis isolates and B. subtilis cocktail were used. The seeds were inoculated by Bacillus subtilis strains at a concentration of 2 x 108 CFU mL-1 using direct application technique of planting on graves. Biomass parameters, relative efficiency (RE), phosphorus content and phosphate utilization efficiency (P-UEF) were evaluated. The treatment with natural phosphate fertilization and B. subtilis UFTBs 06 and B. subtilis cocktail inoculation promoted a significant increase in biomass of 111% and 93% on relative efficiency (RE) in relation to the control, respectively. On the other hand, B. subtilis UFTBs 07 and B. subtilis cocktail were able to promote the biomass increase without natural phosphate fertilization of 85% and 95% on relative efficiency (RE) in relation to control, respectively. Therefore, B. subtilis cocktail without fertilization and B. subtilis UFTBs 07 with phosphate fertilization increased their phosphate utilization efficiency (P-UEF) in 256% and 150% in relation to the control, respectively. The most of isolates provided a higher phosphorus content available in soil and aerial part of soybean plants.