In Vitro Antagonistic Activity of Plant Growth Promoting Rhizobacteria Against Aggressive Biotypes of the Green Mold

During the cultivation of button mushrooms, the green mold epidemic, which causes a decrease in productivity, is a very important problem. The environmental harm of chemicals used in the control of such epidemics and the demand of consumers for organic products without chemicals have brought environmentally friendly biological control to the fore. Biological control can be achieved by the use of antagonistic microorganisms and their metabolites. In this study, the effectiveness of Bacillus spp. and Pseudomonas spp. for the biological control of the aggressive biotypes of the green mold disease agent Trichoderma aggressivum strains was examined in vitro. For this purpose, the antifungal effects of Bacillus spp. and Pseudomonas spp. against T. aggressivum strains were examined by in vitro dual culture test. Afterward, the antifungal activity of Bacillus spp. metabolites was assessed further using the agar well diffusion method. Then, it was determined whether the bacterial strains showing antifungal activity showed antagonistic activity against A. bisporus. Although none of the Pseudomonas spp. showed antifungal activity against T. aggressivum strains, most of the Bacillus spp. were found to have high activity. It has been concluded that Bacillus sp. Ö-4-82 may be potential biological control agent for button mushroom cultivation.