Volatile Compound-Mediated Recognition and Inhibition Between Biocontrol Agents and .

Certain strains protect plants from diverse pathogens using multiple mechanisms. We report a novel mechanism that may potentially play an important role in -based biocontrol. and significantly increased the amount/activity of secreted antifungal metabolites in response to volatile compounds (VCs) produced by 13 strains of , a soilborne fungus that infects diverse plants. This response suggests that both spp. recognize the presence of by sensing pathogen VCs and prepare for attacking pathogens. However, did not respond to any, while responded to VCs from only a few strains. Gene expression analysis via qPCR showed up-regulation of several biocontrol-associated genes in in response to VCs. Analysis of VCs from seven strains tentatively identified a total of 28 compounds, including six that were produced by all of them. All four species produced VCs that inhibited growth. Analysis of VCs produced by and revealed the production of compounds that had been reported to display antifungal activity. also recognizes spp. by sensing their VCs and releases VCs that inhibit , suggesting that both types of VC-mediated interaction are common among fungi.