The mycorrhizal communities of Lophomyrtus bullata Burret (Myrtaceae) within three natural forest associations of New Zealand

The widespread endemic tree Lophomyrtus bullata (ramarama; Myrtaceae) is in serious decline. Lophomyrtus bullata is now considered threatened due to the ongoing spread of Austropuccinia psidii, a rust fungus causing myrtle rust disease. Mycorrhizal communities play an important role in the survival of plant species and have a potential role in disease resistance. Thus, we examined the fungal communities of L. bullata, with special emphasis on the arbuscular mycorrhizal fungi, together with vegetation and site characteristics in three forest associations in Northern New Zealand. Molecular analyses demonstrated a diverse fungal community, including representatives of nine families of arbuscular mycorrhizae. The family Archaeosporaceae was particularly abundant and diverse. Other fungal phyla (Ascomycota, Basidiomycota, and Zygomycota) were also found to associate with L. bullata. Mycorrhizal species composition across vegetation associations was similar but abundances differed. This is the first study to demonstrate the multiple fungal species associated with L. bullata, which may help in the remediation of this vulnerable plant.