Plant herbivore protection by arbuscular mycorrhizas : a role for fungal diversity?

Our purpose here is to briefly outline key mechanisms by which the AM symbiosis enhances plant defences to insect herbivores; summarize where research has made progress in understanding the role of fungal diversity in plant defences against insect herbivory; emphasize why it is important to understand how AM fungal diversity determines plant defence outcomes while highlighting the key knowledge gaps to be addressed