Use of Bacillus subtilis as biocontrol agent. I. Activities and characterization of Bacillus subtilis strains

Selected Bacillus strains, isolated from infested soils and biochemically characterized by BERGEY's method as Bacillus subtilis, were investigated with respect co their antibacterial, antifungal and plant growth-promoting efficacy in order to describe their characteristics. Dependences of the antifungal activity on nutrient requirement, pH-value and incubation temperature in vitro were found. Complementary exact characterization of the Bacillus subtilis strains, using the lysotype method, resulted in classification to species amyloliquefaciens of some antagonistic strains within the Bacillus subtilis group. Additionally, the specific pattern of secondary metabolites produced during fermentation were compared and used for characterization of strains. All the monitored activities and formulation properties suggest an effective use of Bacillus subtilis for biocontrol. A new bioproduct "FZB24" is registered in Germany as a plant-strengthening agent.