Plant–Plant Communication Through Common Mycorrhizal Networks

Mycorrhizal fungi can interconnect individual plants to form common mycorrhizal networks (CMNs). Recent work has shown that these networks can transport signals produced by plants in response to herbivore and pathogen infestation to neighbouring plants before they are themselves attacked. The speed of transfer to uninfested plants is such that the mechanism is likely to have measurable benefits for plant protection. At present, the nature of the signals and the degree of plant and fungal control of their delivery are unknown. Interplant communication of signals via mycorrhizal fungi means we must rethink our understanding of multitrophic interactions in nature, and the findings have led to several hypotheses concerning the evolutionary outcomes of the process. We urgently need to better understand the mechanisms of signal transfer in natural plant communities, and attempt to harness the formation of CMNs as a tool for sustainable pest management in agriculture.