E&E Seminar: Switching partners – diverse mycorrhizal partnerships with eucalypts

The vast majority of plants are mycorrhizal, with two of the most dominant types (arbuscular [AM] and ectomycorrhizal [EcM]) existing at opposite ends of multiple spectra. Most plants form symbiosis with only one of these two types but a few groups (including many Eucalyptus spp.) can associate with both, with some observing that the frequency of each type depends on the plant growth stage. This has led to hypotheses that host seedlings, saplings and trees might derive benefit from these partnerships differently and that the occurrence of each type is driven by stage-specific host requirements. In this talk, I share evidence suggesting that the occurrence of AM and EcM fungi in eucalypt woodlands is driven more by the health of the broader ecosystem than by the needs of the host. This has consequences for ecosystem recovery and restoration, as well as for our general understanding of diverse mycorrhizal systems.