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Home • Armillaria ectypa FPL83.16 v1.0
http://www.nifg.org.uk/species/atlas2.htm?item=BMSSYS0000020524
Fruiting bodies of Armillaria ectypa growing on Sphagnum papillosum (Bog moss). The mature fruiting bodies are upto 10 cm high with about 5 cm caps in diameter. [Photo source: Northern Ireland Fungus Group; credit: Mark Wright]

The Armillaria ectypa genome was sequenced as part of the JGI CSP “1000 Fungal Genomes – Deep Sequencing of Ecologically-relevant Dikarya” project. Within the framework of this project, we are sequencing keystone lineages of saprophytic, mycorrhizal, and endophytic fungi that are of special ecological importance. Dozens of sequenced species were harvested from Long Term Observatories to serve as the foundation for a reference database for metagenomics of fungi and for a comprehensive survey of the soil fungal metatranscriptome.

Members of the genus Armillaria belong to Physalacriaceae, a highly diverse family in the Agaricales containing white rot wood decayers and devastating tree pathogens. They cause shoestring root rot, which lead to significant losses in forest areas or woody plants, including forests, parks or vineyards, among others, mostly in the temperate zone. The infection is usually characterized by the presence of rhizomorphs and mycelial mats between the bark and cambium layer of the host root. Rhizomorphs are shoestring-like multicellular structures, which are analogous to plant roots in appearance and forage for food by spreading inside the soil. Armillaria spp. produce macroscopic fruiting bodies that are edible and known as honey mushrooms. Many existing individuals of Armillaria are believed to be the largest and oldest terrestrial organisms known on earth.

We aim to sequence the genomes of several Armillaria strains representing both aggressive pathogens and white-rot saprotrophs. This will allow us to gain insights into the evolution of pathogenicity and the mechanisms of interaction between Armillaria and their host trees. It will further help understanding the biology of these species, including their strategies for host invasion, for wood decay, and the development of rhizomorphs and fruiting bodies. We hope these resources will open the door for developing efficient management strategies for limiting the spread and damage to forest ecosystems.

Armillaria ectypa (Fr.) Lamoure, commonly known as the Marsh Honey Fungus is listed as a Near Threatened Eurasian species under the IUCN Red List of Threatened Species (2015)2A. ectypa belongs to the Desarmillaria subgenus which are characterized by exannulate stipes. It is probably the only Armillaria species which is not linked to degradation of wood, rather is saprotrophic on decaying peat moss and other bryophytes1,3. The habitat preferences are majorly confined to niches with low nitrogen availability and alkaline microhabitats. A. ectypa can be found typically in alkaline mires, ombrogenous peat bogs, and reeds where the species diversity ranges from mosses to flowering plant species, suggesting that A. ectypa also plays a role in nutrient cycling in wetlands.

The 1KFG project is a large collaborative effort aiming for master publication(s). Please do contact the PI for 1KFG - Deep Sequencing of Ecologically-relevant Dikarya (Dr. Francis Martin) for permission prior to the use of any data in publications.

References:

  1. Koch et. al., (2017). Resolved phylogeny and biogeography of the root pathogen Armillaria and its gasteroid relative, Guyanagaster. BMC Evolutionary Biology. 17(33):1-16. doi: 10.1186/s12862-017-0877-3
  2. Svetasheva, T. (2015). Armillaria ectypa. The IUCN Red List of Threatened Species 2015: e. T75097245A75098379. doi: 10.2305/IUCN.UK.2015-4.RLTS.T75097245A75098379.en
  3. Ainsworth, M. (2003). Report on the marsh honey fungus, Armillaria ectypa, a UK BAP species. English Nature Research Reports No. 540 English Nature Publications.