Archaeorhizomycetes

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Archaeorhizomycetes
Scientific classification Red Pencil Icon.png
Kingdom: Fungi
Division: Ascomycota
Subdivision: Taphrinomycotina
Class: Archaeorhizomycetes
Rosling and T.James
Order: Archaeorhizomycetales
Rosling and T.James
Family: Archaeorhizomycetaceae
Rosling and T.James
Genus: Archaeorhizomyces
Rosling and T.James
Type species
Archaeorhizomyces finlayi
Rosling and T.James (2011)

Archaeorhizomycetes is a class of fungi in the subdivision Taphrinomycotina of the Ascomycota. So far, the class has only one described order, Archaeorhizomycetales, family, Archaeorhizomycetaceae, and genus, Archaeorhizomyces. The class was first described by a team led by Anna Rosling in 2011. Species in the class are globally distributed, and grow in soil and around roots. [1] [2] Specific known host trees of various Archaeorhizomyces species include hemlock, spruce, pine and heather, but other species colonise hardwoods generally. [1]

The precise ecological role of the taxa is uncertain. While originally found to be seasonal, suggesting it was dependent on carbon compounds from the roots, when grown in culture, Archaeorhizomyces finlayi, was shown to be able to grow using either glucose or cellulose as its sole source of carbon, suggesting "that it may be involved in decomposition and not require direct carbon transfer from the plant through symbiosis". [1] While the ecological role is not yet clear, preliminary tests suggest that the fungus is neither a pathogen nor an ectomycorrhizal symbiont. [3]

Prior to the description by Rosling and colleagues, Archaeorhizomycetes was referred to as Soil Clone Group 1 or SCGI after it was originally discovered tundra soils and reported in 2003 by Schadt et al. [4] The taxa were only known from ribosomal DNA sequencing but it had been found independently in ecological studies of soil in more than fifty cases worldwide using three different gene regions. [5] However, neither fruit bodies nor spores had been observed. [1]

The name Archaeorhizomyces comes from the Greek arkhaio-, meaning ancient, which is in reference to the basality of the fungus, rhiza, in reference to roots, and mykes, in reference to fungi. Archaeorhizomyces finlayi , (named in honour of Roger D. Finlay) was the first species described. It is known from Scandinavia and North America. [1] A second species Archaeorhizomyces borealis was described in 2014 together with an estimate that the class may consist of close to 500 species based on sequences available in public databases. [6]

Related Research Articles

<span class="mw-page-title-main">Mycelium</span> Vegetative part of a fungus

Mycelium is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Fungal colonies composed of mycelium are found in and on soil and many other substrates. A typical single spore germinates into a monokaryotic mycelium, which cannot reproduce sexually; when two compatible monokaryotic mycelia join and form a dikaryotic mycelium, that mycelium may form fruiting bodies such as mushrooms. A mycelium may be minute, forming a colony that is too small to see, or may grow to span thousands of acres as in Armillaria.

<span class="mw-page-title-main">Mycorrhiza</span> Fungus–plant symbiotic association

A mycorrhiza is a symbiotic association between a fungus and a plant. The term mycorrhiza refers to the role of the fungus in the plant's rhizosphere, its root system. Mycorrhizae play important roles in plant nutrition, soil biology, and soil chemistry.

<span class="mw-page-title-main">Lichen</span> Symbiosis of fungi with algae or cyanobacteria

A lichen is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship. Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not plants. They may have tiny, leafless branches (fruticose); flat leaf-like structures (foliose); grow crust-like, adhering tightly to a surface (substrate) like a thick coat of paint (crustose); have a powder-like appearance (leprose); or other growth forms.

<span class="mw-page-title-main">Endophyte</span>

An endophyte is an endosymbiont, often a bacterium or fungus, that lives within a plant for at least part of its life cycle without causing apparent disease. Endophytes are ubiquitous and have been found in all species of plants studied to date; however, most of the endophyte/plant relationships are not well understood. Some endophytes may enhance host growth, nutrient acquisition and improve the plant's ability to tolerate abiotic stresses, such as drought and decrease biotic stresses by enhancing plant resistance to insects, pathogens and herbivores. Although endophytic bacteria and fungi are frequently studied, endophytic archaea are increasingly being considered for their role in plant growth promotion as part of the core microbiome of a plant.

<span class="mw-page-title-main">Arbuscular mycorrhiza</span> Symbiotic penetrative association between a fungus and the roots of a vascular plant

An arbuscular mycorrhiza (AM) is a type of mycorrhiza in which the symbiont fungus penetrates the cortical cells of the roots of a vascular plant forming arbuscules.

<span class="mw-page-title-main">Glomeromycota</span> Phylum of fungi

Glomeromycota are one of eight currently recognized divisions within the kingdom Fungi, with approximately 230 described species. Members of the Glomeromycota form arbuscular mycorrhizas (AMs) with the thalli of bryophytes and the roots of vascular land plants. Not all species have been shown to form AMs, and one, Geosiphon pyriformis, is known not to do so. Instead, it forms an endocytobiotic association with Nostoc cyanobacteria. The majority of evidence shows that the Glomeromycota are dependent on land plants for carbon and energy, but there is recent circumstantial evidence that some species may be able to lead an independent existence. The arbuscular mycorrhizal species are terrestrial and widely distributed in soils worldwide where they form symbioses with the roots of the majority of plant species (>80%). They can also be found in wetlands, including salt-marshes, and associated with epiphytic plants.

<span class="mw-page-title-main">Saccharomycotina</span> Subdivision of fungi

Saccharomycotina is a subdivision (subphylum) of the division (phylum) Ascomycota in the kingdom Fungi. It comprises most of the ascomycete yeasts. The members of Saccharomycotina reproduce by budding and they do not produce ascocarps.

Glomus is a genus of arbuscular mycorrhizal (AM) fungi, and all species form symbiotic relationships (mycorrhizae) with plant roots. Glomus is the largest genus of AM fungi, with ca. 85 species described, but is currently defined as non-monophyletic.

<span class="mw-page-title-main">Fungivore</span> Organism that consumes fungi

Fungivory or mycophagy is the process of organisms consuming fungi. Many different organisms have been recorded to gain their energy from consuming fungi, including birds, mammals, insects, plants, amoebas, gastropods, nematodes, bacteria and other fungi. Some of these, which only eat fungi, are called fungivores whereas others eat fungi as only part of their diet, being omnivores.

Archaeorhizomyces finlayi is a species of fungi in the class Archaeorhizomycetes and the type species. When the class was described in 2011, a single order, Archaeorhizomycetales, family, Archaeorhizomycetaceae, genus, Archaeorhizomyces and species, Archaeorhizomyces finlayi, were described, though other species are known to exist. A. finlayi is named in honour of Roger D. Finlay.

<span class="mw-page-title-main">Mycorrhizal network</span> Underground hyphal networks that connect individual plants together

A Mycorrhizal network is an underground network found in forests and other plant communities, created by the hyphae of mycorrhizal fungi joining with plant roots. This network connects individual plants together and transfers water, carbon, nitrogen, and other nutrients and minerals between participants. Several studies have demonstrated that mycorrhizal networks can transport carbon, phosphorus, nitrogen, water, defense compounds, and allelochemicals from plant to plant. The flux of nutrients and water through hyphal networks has been proposed to be driven by a source–sink model, where plants growing under conditions of relatively high resource availability transfer carbon or nutrients to plants located in less favorable conditions. A common example is the transfer of carbon from plants with leaves located in high-light conditions in the forest canopy, to plants located in the shaded understory where light availability limits photosynthesis. In natural ecosystems, plants may be dependent on fungal symbionts for 90% of their phosphorus requirements and 80% of their nitrogen requirements. Mycorrhizal relationships are most commonly mutualistic, with both partners benefiting, but can be commensal or parasitic.

<span class="mw-page-title-main">Mycorrhizal fungi and soil carbon storage</span>

Soil carbon storage is an important function of terrestrial ecosystems. Soil contains more carbon than plants and the atmosphere combined. Understanding what maintains the soil carbon pool is important to understand the current distribution of carbon on Earth, and how it will respond to environmental change. While much research has been done on how plants, free-living microbial decomposers, and soil minerals affect this pool of carbon, it is recently coming to light that mycorrhizal fungi—symbiotic fungi that associate with roots of almost all living plants—may play an important role in maintaining this pool as well. Measurements of plant carbon allocation to mycorrhizal fungi have been estimated to be 5 to 20% of total plant carbon uptake, and in some ecosystems the biomass of mycorrhizal fungi can be comparable to the biomass of fine roots. Recent research has shown that mycorrhizal fungi hold 50 to 70 percent of the total carbon stored in leaf litter and soil on forested islands in Sweden. Turnover of mycorrhizal biomass into the soil carbon pool is thought to be rapid and has been shown in some ecosystems to be the dominant pathway by which living carbon enters the soil carbon pool.

<span class="mw-page-title-main">Ectomycorrhiza</span> Non-penetrative symbiotic association between a fungus and the roots of a vascular plant

An ectomycorrhiza is a form of symbiotic relationship that occurs between a fungal symbiont, or mycobiont, and the roots of various plant species. The mycobiont is often from the phyla Basidiomycota and Ascomycota, and more rarely from the Zygomycota. Ectomycorrhizas form on the roots of around 2% of plant species, usually woody plants, including species from the birch, dipterocarp, myrtle, beech, willow, pine and rose families. Research on ectomycorrhizas is increasingly important in areas such as ecosystem management and restoration, forestry and agriculture.

<span class="mw-page-title-main">Ectomycorrhizal extramatrical mycelium</span>

Ectomycorrhizal extramatrical mycelium is the collection of filamentous fungal hyphae emanating from ectomycorrhizas. It may be composed of fine, hydrophilic hypha which branches frequently to explore and exploit the soil matrix or may aggregate to form rhizomorphs; highly differentiated, hydrophobic, enduring, transport structures.

<span class="mw-page-title-main">Root microbiome</span>

The root microbiome is the dynamic community of microorganisms associated with plant roots. Because they are rich in a variety of carbon compounds, plant roots provide unique environments for a diverse assemblage of soil microorganisms, including bacteria, fungi and archaea. The microbial communities inside the root and in the rhizosphere are distinct from each other, and from the microbial communities of bulk soil, although there is some overlap in species composition.

Roy Watling, PhD., DSc, FRSE, F.I.Biol., C.Biol., FLS is a Scottish mycologist who has made significant contributions to the study of fungi both in the identification of new species and correct taxonomic placement, as well as in fungal ecology.

<i>Phellodon niger</i>

Phellodon niger, commonly known as the black tooth, is a species of tooth fungus in the family Bankeraceae, and the type species of the genus Phellodon. It was originally described by Elias Magnus Fries in 1815 as a species of Hydnum. Petter Karsten included it as one of the original three species when he circumscribed Phellodon in 1881. The fungus is found in Europe and North America, although molecular studies suggest that the North American populations represent a similar but genetically distinct species.

Orchid mycorrhizae are endomycorrhizal fungi which develop symbiotic relationships with the roots and seeds of plants of the family Orchidaceae. Nearly all orchids are myco-heterotrophic at some point in their life cycle. Orchid mycorrhizae are critically important during orchid germination, as an orchid seed has virtually no energy reserve and obtains its carbon from the fungal symbiont.

Mycorrhizae and climate change refers to the effects of climate change on mycorrhizae, a fungus which forms an endosymbiotic relationship between with a vascular host plant by colonizing its roots, and the effects brought on by climate change. Climate change is any lasting effect in weather or temperature. It is important to note that a good indicator of climate change is global warming, though the two are not analogous. However, temperature plays a very important role in all ecosystems on Earth, especially those with high counts of mycorrhiza in soil biota.

<span class="mw-page-title-main">Mucoromycota</span> A phylum within kingdom fungi

Mucoromycota is a division within the kingdom fungi. It includes a diverse group of various molds, including the common bread molds Mucor and Rhizopus. It is a sister phylum to Dikarya.

References

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  2. "New fungi class formally identified". Science Daily. 11 August 2011. Retrieved 14 August 2011.
  3. ""Boring" fungus finally gets a name". Futurity.org. 16 August 2011. Retrieved 19 August 2011.
  4. Schadt, Christopher W. (2003). "Seasonal Dynamics of Previously Unknown Fungal Lineages in Tundra Soils". Science. 301 (5638): 1359–1361. Bibcode:2003Sci...301.1359S. doi:10.1126/science.1086940. PMID   12958355. S2CID   22753815.
  5. Porter, Terri M. (2008). "Widespread occurrence and phylogenetic placement of a soil clone group adds a prominent new branch to the fungal tree of life". Molecular Phylogenetics and Evolution. 46 (2): 635–644. doi:10.1016/j.ympev.2007.10.002. PMID   18032071.
  6. Audrius Menkis; Hector Urbina; Timothy Y. James; Anna Rosling (2014). "Archaeorhizomyces borealis sp. nov. and a sequence-based classification of related soil fungal species". Fungal Biology . 118 (12): 943–955. doi:10.1016/j.funbio.2014.08.005. PMID   25457942.