Microbial volatiles organic compounds control anthracnose (Colletotrichum lindemuthianum) in common bean (Phaseolus vulgaris L.)

Some microbial volatile organic compounds (mVOCs) can be toxic to phytopathogens, but information about their in vivo effect and the contribution of individual mVOC to biocontrol is scarce. In this study, we evaluated the in vitro and in vivo effect of Bacillus amylolicefaciens ALB629 and UFLA285 mVOCs on anthracnose (Colletotrichum lindemuthianum) control in common bean (Phaseolus vulgaris L.). ALB629 reduced C. lindemuthianum spore numbers (31%), while UFLA285 and ALB629 inhibited mycelial growth by 16 and 18%, respectively. Both bacterial volatiles controlled anthracnose in vivo (79-85%). The volatiles from UFLA285 and ALB629, identified as 3-methylbutanoic acid and 2-methylbutanoic acid, were toxic to the pathogen when applied individually or in combination, likely being the ones that play a role in common bean protection against anthracnose. Bacterial-VOCs- 3-methylbutanoic acid and/or 2-methylbutanoic acid could be used to protect common bean against anthracnose.