Cracking the plant VOC sensing code and its practical applications

HighlightsPlant–plant (interplant) interactions via volatile organic compounds (VOCs) emitted by plants confer antiherbivore capabilities on the plants receiving these VOCs.Interplant interactions occur with both conspecific and heterospecific neighboring plants, relying on VOCs emitted by herbivore-damaged plants as well as unique or constitutively emitted compounds such as isoprene and fragrant grass VOCs.VOCs are taken up through stomata and diffuse across mesophyll cells in leaves. The mechanisms underlying cellular recognition and uptake of VOCs, likely involving receptors and transporters, are not well understood.Chromatin remodeling and transcriptional regulation are the basis for gene activation for defense responses in VOC-receiving plants.VOC-emitting companion plants and VOC biostimulants may provide sustainable agricultural and horticultural technologies.AbstractVolatile organic compounds (VOCs) are essential airborne mediators of interactions between plants. These plant–plant interactions require sophisticated VOC-sensing mechanisms that enable plants to regulate their defenses against pests. However, these interactions are not limited to specific plants or even conspecifics, and can function in very flexible interactions between plants. Sensing and responding to VOCs in plants is finely controlled by their uptake and transport systems as well as by cellular signaling via, for example, chromatin remodeling system-based transcriptional regulation for defense gene activation. Based on the accumulated knowledge about the interactions between plants and their major VOCs, companion plants and biostimulants are being developed for practical applications in agricultural and horticultural pest control, providing a sustainable alternative to harmful chemicals.