Mitigating the trade-off between growth and stress resistance in plants by fungal volatile compounds.

Plants grow in association with diverse microorganisms. During communication between plants and microbes, beneficial and phytopathogenic bacteria and fungi emit various volatile compounds (VCs). These microbial VCs (mVCs) are typically small, odorous compounds with low boiling point, high vapor pressure, and a lipophilic moiety (Schulz and Dickschat, 2007). Based on recent studies, mVCs appear to regulate plant nutrient acquisition, photosynthesis, phytohormone actions, and metabolic processes, leading to an improvement in plant performance (Fincheira et al., 2021). Since mVCs can activate plant defenses, and/or promote plant growth and development at low concentrations, their application in agriculture is attractive to efficiently grow crops and improve plant health in the absence of excess usage of chemical fertilizers and pesticides. To this end, mVCs have been used for integrated pest management (IPM) to enhance both crop defense and production in field conditions (Brilli et al., 2019). Understanding the molecular action of mVCs in plants will pave the way toward improved crop protection and ecosystem management.