Networking via mycorrhizae

Highlights

	● Evidence for interplant communication via common mycorrhizal networks is reviewed.
	● Potential transport routes for semiochemicals via fungal hyphae are identified.
	● Drivers of signal exchange via CMNs are discussed.

Abstract

Interplant communication is of vital importance for plant performance in natural environments. Mycorrhizal fungi have emerged as key contributors to the below ground communication between plants. These mutualistic fungi form connections between the roots of plants via their hyphae, known as common mycorrhizal networks (CMNs). These hyphal networks are thought to be important ways for the exchange of signals between plants. This paper reviews the evidence for CMN-based transfer of semiochemicals between plants upon exposure to pathogen infection, herbivory or mechanical damage. Potential transport routes are explored, asking whether the fungi can actively contribute to the distribution of such signals within the network and discussing potential drivers for signal exchange. It is concluded that identification of the signals that are exchanged remains an important challenge for the future.

Graphical abstract

Keywords

Mycorrhizal fungi / common mycorrhizal network / signal transfer / defensive response

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Acknowledgements

Xiaofan Ma is supported by the China Scholarship Council (201913043).

Compliance with ethics guidelines

Xiaofan Ma and Erik Limpens declare that they have no conflicts of interest or financial conflicts to disclose. This article does not contain any studies with human or animal subjects performed by any of the authors.

RIGHTS & PERMISSIONS

The Author(s) 2024. Published by Higher Education Press. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0)