Home • Amylostereum chailletii DWAch2 v1.0
Fruiting bodies of the crust fungus Amylostereum chailletii on Picea abies. Note the exit holes of the siricid woodwasps forming symbiotic associations with A. chailletii. (credit : Bernard Slippers, University of Pretoria).
Fruiting bodies of the crust fungus Amylostereum chailletii on Picea abies. Note the exit holes of the siricid woodwasps forming symbiotic associations with A. chailletii. (credit : Bernard Slippers, University of Pretoria).

Within the framework of the 1000 Fungal Genomes (1KFG) project “Deep Sequencing of Ecologically-relevant Dikarya“ (CSP1974), we are sequencing genomes of ecologically-relevant fungal species to get a better understanding of the evolution of major nutritional modes in forest fungi and to provide sufficient taxonomic coverage of fungal genomes to identify and analyze DNA and RNA samples sequenced from environmental samples.

Amylostereum chailletii

Amylostereum chailletii is a basidiomycete in the order Russulales, which is best known for conspicuous ectomycorrhizal (ECM) gilled mushrooms in the genera Russula and Lactarius. In contrast, A. chailletii is a white-rot wood-decayer that has a tough, mostly resupinate (crust-like) fruiting body, with a partially reflexed margin. Amylostereum chailletii joins a growing list of Russulales genomes, which already includes wood-decayers with coralloid, resupinate, and gilled mushroom forms (e.g., Artomyces pyxidatus, Peniophora sp., Lentinellus vulpinus), timber pathogens (Heterobasidion annosum), as well as the aforementioned ECM mushrooms (Lactarius quietus and several species of Russula), among others. Thus, the Russulales is becoming a model clade for genome-based investigations of morphological and ecological diversification in Agaricomycetes.

Several species of Amylostereum form symbiotic associations with siricid woodwasps (Hymenoptera, Siricidae). The association is facultative for the fungi, but obligate for the insects. Adult female siricids carry fungal inoculum in specialized organs called mycangia and deposit fungal propagules into wood of living Pinaceae and Cupressaceae at the time of oviposition. The resulting decay of the wood is essential for the feeding of the insect larvae. Insect-mediated dispersal may lead to clonal lineages with large geographic ranges, but the fungus also reproduces sexually via basidiospores. Together, the siricid-Amylostereum association constitutes a serious timber pathogen, particularly in pine plantations outside of the native range of Pinaceae (e.g., New Zealand and South Africa). At least five species of Amylostereum are recognized, and several, including A. chailettii form associations with siricids, and species-level taxonomy within the group is now relatively well resolved. The siricid-Amylostereum association has been widely studied. The genome of A. chailletii will open the door to further investigations into the genetic mechanisms of “domestication” of a white rot fungus.

The 1KFG project is large collaborative efforts aiming for master publication(s). As always, please contact the PI associated with unpublished 1KFG genomes for permission prior to the use of any data in publications.

References

Slippers, Bernard; de Groot, Peter; Wingfield Michael J. 2012. The Sirex Woodwasp and its Fungal Symbiont: Research and Management of a Worldwide Invasive Pest. Springer.

Larsson, Ellen; Larsson, Karl-Henrik. 2003. Phylogenetic relationships of russuloid basidiomycetes with emphasis on aphyllophoralean taxa. Mycologia 95: 1037–1065.

Slippers, Bernard; Coutinho, Teresa A.; Wingfield, Brenda D.; Wingfield, Michael J. 2003. A review of the genus Amylostereum and its association with woodwasps. South African Journal of Science 99: 70–74.

Fitza, Katrin N.E.; Tabata, Masanobu; Kanzaki, Natsumi; Kimura, Koki; Garnas, Jeff; Slippers, Bernard. 2016. Host specificity and diversity of Amylostereum associated with Japanese siricids. Fungal Ecology 24: 76-81.

Genome Reference(s)