Three fungal phyla, which form mycorrhizas in higher plants, also form symbiotic fungal associations in liverworts. Zygomycetous fungi colonise a range of thalloid liverworts where they produce structures analogous to those seen in the vesicular-arbuscular (VA) mycorrhizas of higher plants. Experiments reveal that glomalean fungi forming typical VA mycorrhizas with a higher plant (Plantago lanceolata) can colonise a thalloid liverwort (Pellia fabroniana) producing arbuscules and vesicles in the thallus. Some members of the Jungermanniales and Metzgeriales form associations with basidiomycetous fungi, which produce intracellular hyphal coils similar to the pelotons seen in orchid mycorrhizas. The fungal associates of the autotrophic Aneura pinguis and its heterotrophic relative Cryptothallus mirabilis have been isolated. Resynthesis experiments have shown that the fungal symbiont of Cryptothallus is an ectomycorrhizal associate of Betula suggesting an explanation for the apparently obligate nature of the association between the two. Ascomycetous associations are found in the Cephaloziaceae and Lepidoziaceae. Cross-inoculation experiments have shown that a typical mycorrhizal endophyte of ericaceous plants, Hymenoscyphus ericae will colonise the rhizoids and underground axes of these plants. Ascomycete-containing hepatics are particularly conspicuous associates of the Ericaceae and Epacridaceae. Metzgeralean genera with VA-fungi are most diverse in the podocarp forests of New Zealand. Nutrient exchange between these hepatics and seed plants via common mycobionts is currently under investigation.

Key words: ascomycete, basidiomycete, liverwort, mycorrhiza, symbiosis, vesicular-arbuscular (VA)