Russula is a large genus of fungi containing both mushroom and truffle-like species, most of which form ectomycorrhizal associations with trees. Russula seminuda forms this symbiotic link with Eucalyptus nitens, a plantation tree. The fungus forms a sock-like mantle around roots and the fungal hyphae grow in-between the plant cells forming a Hartig net where carbon from photosynthesis by the plant is exchanged for phosphorus, nitrogen and water from the fungus. The fine mycelial strands of the fungus are able to access supplies of water and minerals from parts of the soil structure denied to the thicker plant roots. This symbiosis makes R. seminuda one of those fungi indispensable for the health of plantations of the fast growing Eucalypts that are suitable for energy crops. R. seminuda is a truffle-like fungus which is dependent on being eaten by small mammals for the dispersal of its spores, a lifestyle that is adaptive in a dry climate as it reduces desiccation, a significant risk for fungi with emergent fruiting bodies that scatter spores by wind. The genome of R. seminuda will help reveal how truffle-like species evolved from closely related mushroom like Russula species by comparison of the genomes of species with different fruitbody forms. Given current predictions of a drying climate, understanding pathways to this adaptation and how to manipulate their genetics may be vital knowledge for managing the health of future forestry energy plantations.
Previous name: Cystangium seminudum (Massee & Rodway) T. Lebel & Castellano, Mycologia 94: 337 (2002). Tas., L. Rodway 124; Holotype: HO.