Cortinarius is a large genus of fungi containing both
mushroom and truffle like species, most of which form
ectomycorrhizal associations with trees. Cortinarius
austrovenetus is broadly distributed in
Eucalyptus forests in southern Australia and is thought to
form ectomycorrhizae with a wide range of Eucalypt species. The
fungus forms a sock-like envelope (mantle) around roots and the
hyphae interpenetrate between plant cells forming a Hartig net
where carbon from plant photosynthesis is exchanged for phosphorus,
nitrogen and water. The fine mycelial strands of the fungus can
access supplies of water and minerals from soil locations
inaccessible by the thicker plant roots. This symbiosis makes
C. austrovenetus one of the group of fungi indispensable
for the health of Eucalyptus species, many of which have
potential as energy crops. The lignocellulose of Eucalypt timber
can be used as a feedstock for processes under development that use
fungi to produce fuel ethanol. The genome of C.
austrovenetus will help reveal how mushroom-like
Cortinarius species gave rise to truffle-like species that
are better adapted to a dry climate. In contrast to the fruiting
bodies of mushroom relatives that disperse spores in the wind and
are vulnerable to desiccation, truffle fruiting bodies are
underground-protected from rapid desiccation and their spores are
dispersed by mycophagous small mammals. Given the predictions of
climate change, understanding pathways to the development of
subterranean fruiting may be crucial for managing the health of
future forestry energy plantations.
