Armillaria tabescens

Last updated

Armillaria tabescens
Armillaria tabescens.JPG
Scientific classification Red Pencil Icon.png
Kingdom: Fungi
Division: Basidiomycota
Class: Agaricomycetes
Order: Agaricales
Family: Physalacriaceae
Genus: Armillaria
Species:
A. tabescens
Binomial name
Armillaria tabescens
(Scop.) Emel (1921)
Synonyms

Agaricus gymnopodiusBull. (1798)
Agaricus gymnopodiussensu Quelét (1948)
Agaricus monadelphusMorgan (1883)
Agaricus socialisDC. (1815)
Agaricus tabescensScop. (1772)
Armillaria mellea var. tabescens(Scop.) Rea & Ramsb. (1917)
Armillaria socialis(DC.) Herink (1973)
Armillariella tabescens(Scop.) Singer
Clitocybe gymnopodiasensu Kühner & Romagnesi (1953)
Clitocybe gymnopodia(Bull.) Gillet (1874)
Clitocybe monadelpha(Morgan) Sacc. (1887)
Clitocybe socialis(DC.) Gillet (1874)
Clitocybe tabescens(Scop.) Bres. (1928)
Collybia tabescens(Scop.) Fr.
Flammula gymnopodia(Bull.) Quél. (1873)
Lentinus caespitosusBerk. (1847)
Monodelphus caespitosus(Berk.) Murrill, (1911)
Omphalia gymnopodiasensu Quélet
Pholiota gymnopodia(Bull.) A.F.M.Reijnders (1998)
Pleurotus caespitosus(Berk.) Sacc. (1887)
Pocillaria caespitosa(Berk.) Kuntze (1891)

Contents

Armillaria tabescens (also known as ringless honey mushroom) is a species of fungus in the family Physalacriaceae. It is a plant pathogen. The mycelium of the fungus is bioluminescent. [1]

Hosts and symptoms

Armillaria species infect a wide variety of woody plants. [2] In a survey of 250 permanent plots of trees in Albania, Armillaria tabescens affected multiple species of trees including fir species, where it invaded when the plant was stressed. [3] Tsopelas et al. [4] reported Armillaria tabescens to be more prevalent in areas where the trees were stressed due to limited moisture. In oak trees, it was slightly more damaging and could kill young trees. Armillaria tabescens was also recorded in poplar and eucalyptus plantations, and almond trees were found to be very susceptible to infection. [4] The results of the study by Lushaj et al. [3] showed that Armillaria tabescens was most frequently recorded on fruit and ornamental trees compared to the other species. [3]

Armillaria tabescens causes separation of the bark from the wood by the production of mycelial fans in the trunk, a common sign of Armillaria root rot. [2] It also causes gummosis, patches of gummy material on the surface of plants, which occurs in response to an external stimulus which causes the plant to ooze sap. [4] Other common symptoms are soft rot of cortex, dwarfing, dieback, wilting, and abnormal coloring of the leaves. [5] Small trees are killed rapidly by Armillaria tabescens and the symptoms aren’t noticeable until the leaves wilt. However, on larger trees symptoms occur earlier and start as a thin crown with small leaves. A crown of a tree refers to any branches or foliage that are growing out from the trunk. Therefore, thinning of the crown would mean reduced branches and leaves. The trees eventually start yellowing and defoliating followed by fast wilting and dying of limbs. The fungus is a white rot so it breaks down lignin in the wood. The breaking down of the lignin leads to the trees becoming hollow. [6]

Environment

Armillaria tabescens is found in warm and dry regions, so it tends to be in southern areas. It has also been found in altitudes ranging from sea level to 1,300 metres (4,300 ft). [3] Studies in Europe have found that it exists in south-east England, France, Hungary, Italy, Portugal, Greece and, rarely, Germany and Switzerland. In Japan, it is very rare; only one isolate of Armillaria tabescens was found out of 59 sites surveyed. [7]

Armillaria tabescens grows quickly at 28–30 °C (82–86 °F) and more slowly at 5 °C (41 °F). [8] If the soil is moist, fruiting bodies are abundant. It is the first to fruit in September, compared to Armillaria mellea and Armillaria gallica. The fruiting bodies can be seen even earlier if the season has been exceptionally wet. [9] Armillaria tabescens grows poorly on sand and produces shorter rhizomorphs. [10] Rhizomorphs are threadlike structures in fungi that are made up of hyphae. Hyphae are branching structures that release enzymes to absorb nutrients from the host.

Pathogenesis

Armillariatabescens is a heterothallic species of Armillaria. Heterothallic species perform anastomosis when haploid monokaryon come in contact with one another. Anastomosis is the connection or opening between two things, in this case the mycelium. Mycelium is the vegetative part of the fungus that consists of hyphae. If the two monokaryons are sexually compatible they form a clamp connection. This results in a mycelium consisting of dikaryotic cells. The dikaryon cells predominate in the vegetative phase. In the basidia karyogamy occurs before meiosis and then the formation of basidiospores. [6] The basidiospores then infect the host plant.

Armillariatabescens is found to attack trees that are already stressed or have a wound. The pathogen can spread its mycelia and get into the trunk or root of a tree. [9] The fungus has the ability to spread its mycelia throughout the root and trunk system and form mycelial mats. Mycelia is damaging to trees because they absorb the nutrients by secreting enzymes to breakdown the plant material. It specifically breaks down lignin because it is a white rot.

2008-07-16 Armillaria tabescens cropped.jpg

No rhizomorphs have been found for Armillaria tabescens in nature. However, Rishbeth and Kile [6] did find rhizomorphs buried in the soil on inocula. Since the species doesn't produce rhizomorphs commonly in the nature, infected roots must come into contact with other potential hosts for infection to occur. So, root grafting provides an effective pathway for the spread of this pathogen. Tsopelas [3] conducted an experiment of inoculating almond trees with Armillaria tabescens and two other Armillaria species. The result of the experiment was that basidiocarps developed 6–8 weeks after the inoculation. The basidiocarps are recognized by not having an annulus around the stalk of the basidium. The basidiospores infect the trees. After two years, it only killed 3 out of the 16 trees and two other trees had symptoms of dieback. [3]

Edibility

The species can be cooked and eaten, even being regarded as choice, [11] but has been reported to cause upset stomachs. [12]

See also

Related Research Articles

<span class="mw-page-title-main">Basidiomycota</span> Division of fungi

Basidiomycota is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya within the kingdom Fungi. Members are known as basidiomycetes. More specifically, Basidiomycota includes these groups: agarics, puffballs, stinkhorns, bracket fungi, other polypores, jelly fungi, boletes, chanterelles, earth stars, smuts, bunts, rusts, mirror yeasts, and Cryptococcus, the human pathogenic yeast. Basidiomycota are filamentous fungi composed of hyphae and reproduce sexually via the formation of specialized club-shaped end cells called basidia that normally bear external meiospores. These specialized spores are called basidiospores. However, some Basidiomycota are obligate asexual reproducers. Basidiomycota that reproduce asexually can typically be recognized as members of this division by gross similarity to others, by the formation of a distinctive anatomical feature, cell wall components, and definitively by phylogenetic molecular analysis of DNA sequence data.

<i>Armillaria</i> Genus of fungi

Armillaria is a genus of fungi that includes the A. mellea species known as honey fungi that live on trees and woody shrubs. It includes about 10 species formerly categorized summarily as A. mellea. Armillarias are long-lived and form the largest living fungi in the world. The largest known organism covers more than 3.4 square miles (8.8 km2) in Oregon's Malheur National Forest and is estimated to be 2,500 years old. Some species of Armillaria display bioluminescence, resulting in foxfire.

<i>Armillaria mellea</i> Species of fungus

Armillaria mellea, commonly known as honey fungus, is a basidiomycete fungus in the genus Armillaria. It is a plant pathogen and part of a cryptic species complex of closely related and morphologically similar species. It causes Armillaria root rot in many plant species and produces mushrooms around the base of trees it has infected. The symptoms of infection appear in the crowns of infected trees as discoloured foliage, reduced growth, dieback of the branches and death. The mushrooms are edible but some people may be intolerant to them. This species is capable of producing light via bioluminescence in its mycelium.

<i>Rhizoctonia solani</i> Species of fungus

Rhizoctonia solani is a species of fungus in the order Cantharellales. Basidiocarps are thin, effused, and web-like, but the fungus is more typically encountered in its anamorphic state, as hyphae and sclerotia. The name Rhizoctonia solani is currently applied to a complex of related species that await further research. In its wide sense, Rhizoctonia solani is a facultative plant pathogen with a wide host range and worldwide distribution. It causes various plant diseases such as root rot, damping off, and wire stem. It can also form mycorrhizal associations with orchids.

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

Mycelial cords are linear aggregations of parallel-oriented hyphae. The mature cords are composed of wide, empty vessel hyphae surrounded by narrower sheathing hyphae. Cords may look similar to plant roots, and also frequently have similar functions; hence they are also called rhizomorphs. As well as growing underground or on the surface of trees and other plants, some fungi make mycelial cords which hang in the air from vegetation.

<i>Armillaria luteobubalina</i> Species of fungus in the family Physalacriaceae.

Armillaria luteobubalina, commonly known as the Australian honey fungus, is a species of mushroom in the family Physalacriaceae. Widely distributed in southern Australia, the fungus is responsible for a disease known as Armillaria root rot, a primary cause of Eucalyptus tree death and forest dieback. It is the most pathogenic and widespread of the six Armillaria species found in Australia. The fungus has also been collected in Argentina and Chile. Fruit bodies have cream- to tan-coloured caps that grow up to 10 cm (4 in) in diameter and stems that measure up to 20 cm (8 in) long by 1.5 cm (1 in) thick. The fruit bodies, which appear at the base of infected trees and other woody plants in autumn (March–April), are edible, but require cooking to remove the bitter taste. The fungus is dispersed through spores produced on gills on the underside of the caps, and also by growing vegetatively through the root systems of host trees. The ability of the fungus to spread vegetatively is facilitated by an aerating system that allows it to efficiently diffuse oxygen through rhizomorphs—rootlike structures made of dense masses of hyphae.

<i>Athelia rolfsii</i> Pathogen fungus

Athelia rolfsii is a corticioid fungus in the family Atheliaceae. It is a facultative plant pathogen and is the causal agent of "southern blight" disease in crops.

<i>Heterobasidion annosum</i> Species of fungus

Heterobasidion annosum is a basidiomycete fungus in the family Bondarzewiaceae. It is considered to be the most economically important forest pathogen in the Northern Hemisphere. Heterobasidion annosum is widespread in forests in the United States and is responsible for the loss of one billion U.S. dollars annually. This fungus has been known by many different names. First described by Fries in 1821, it was known by the name Polyporus annosum. Later, it was found to be linked to conifer disease by Robert Hartig in 1874, and was renamed Fomes annosus by H. Karsten. Its current name of Heterobasidion annosum was given by Brefeld in 1888. Heterobasidion annosum causes one of the most destructive diseases of conifers. The disease caused by the fungus is named annosus root rot.

Rosellinia bunodes is a plant pathogen infecting several hosts including avocados, bananas, cacao and tea.

<i>Rigidoporus microporus</i> Species of fungus

Rigidoporus microporus is a plant pathogen, known to cause white root rot disease on various tropical crops, such as cacao, cassava, tea, with economical importance on the para rubber tree.

<i>Armillaria fuscipes</i> Species of fungus

Armillaria fuscipes is a plant pathogen that causes Armillaria root rot on Pinus, coffee plants, tea and various hardwood trees. It is common in South Africa. The mycelium of the fungus is bioluminescent.

<i>Cyathus stercoreus</i> Species of fungus

Cyathus stercoreus, commonly known as the dung-loving bird's nest or the dung bird's nest, is a species of fungus in the genus Cyathus, family Nidulariaceae. Like other species in the Nidulariaceae, the fruiting bodies of C. stercoreus resemble tiny bird's nests filled with eggs. The fruiting bodies are referred to as splash cups, because they are developed to use the force of falling drops of water to dislodge and disperse their spores. The species has a worldwide distribution, and prefers growing on dung, or soil containing dung; the specific epithet is derived from the Latin word stercorarius, meaning "of dung".

<i>Armillaria novae-zelandiae</i> Species of fungus

Armillaria novae-zelandiae is a species of mushroom-forming fungus in the family Physalacriaceae. This plant pathogen species is one of three Armillaria species that have been identified in New Zealand.

<i>Armillaria gallica</i> Species of fungus in the family Physalacriaceae

Armillaria gallica is a species of honey mushroom in the family Physalacriaceae of the order Agaricales. The species is a common and ecologically important wood-decay fungus that can live as a saprobe, or as an opportunistic parasite in weakened tree hosts to cause root or butt rot. It is found in temperate regions of Asia, North America, and Europe. The species forms fruit bodies singly or in groups in soil or rotting wood. The fungus has been inadvertently introduced to South Africa. Armillaria gallica has had a confusing taxonomy, due in part to historical difficulties encountered in distinguishing between similar Armillaria species. The fungus received international attention in the early 1990s when an individual colony living in a Michigan forest was reported to cover an area of 15 hectares, weigh at least 9.5 tonnes, and be 1,500 years old. This individual is popularly known as the "humongous fungus", and is a tourist attraction and inspiration for an annual mushroom-themed festival in Crystal Falls. Recent studies have revised the fungus's age to 2,500 years and its size to about 400 tonnes, four times the original estimate.

<i>Armillaria</i> root rot

Armillaria root rot is a fungal root rot caused by several different members of the genus Armillaria. The symptoms are variable depending on the host infected, ranging from stunted leaves to chlorotic needles and dieback of twigs and branches. However, all infected hosts display symptoms characteristic of being infected by a white rotting fungus. The most effective ways of management focus on limiting the spread of the fungus, planting resistant species, and removing infected material. This disease poses a threat to the lumber industry as well as affecting recreational areas.

<i>Armillaria ostoyae</i> Species of fungus

Armillaria ostoyae is a species of fungus (mushroom), pathogenic to trees, in the family Physalacriaceae. In the western United States, it is the most common variant of the group of species under the name Armillaria mellea. A. ostoyae is common on both hardwood and conifer wood in forests west of the Cascade Range in Oregon, United States. It has decurrent gills and the stipe has a ring. The mycelium invades the sapwood and is able to disseminate over great distances under the bark or between trees in the form of black rhizomorphs ("shoestrings"). In most areas of North America, Armillaria ostoyae can be separated from other species by its physical features: cream-brown colors, prominent cap scales, and a well-developed stem ring distinguish it from other Armillaria.

<i>Heterobasidion irregulare</i> Species of fungus

Heterobasidion irregulare is a tree root rotting pathogenic fungus that belongs to the genus Heterobasidion, which includes important pathogens of conifers and other woody plants. It has a wide host and geographic range throughout North America and causes considerable economic damage in pine plantations in the United States. This fungus is also a serious worry in eastern Canada. Heterobasidion irregulare has been introduced to Italy (Lazio)(modifica) where it has been responsible for extensive tree mortality of stone pine. Due to the ecology, disease type, host range/preference, interfertility group, and genetic information, H. irregulare was designated a new species and distinguished from Heterobasidion occidentale.

<i>Serpula himantioides</i> Species of fungus

Serpula himantioides is a species of fungus that causes damage to timber referred to as dry rot. It is a basidiomycete in the order Boletales. It has been found on all continents except for Antarctica. Recent molecular work demonstrates that S. himantioides is a species complex including multiple cryptic lineages.

Phytophthora quercina is a papillate homothallic soil-borne plant pathogen causing root rot of oak tree species in Europe. It is associated with necrotic fine roots.

References

  1. Mihail JD. (2015). "Bioluminescence patterns among North American Armillaria species". Fungal Biology. 119 (6): 528–537. doi:10.1016/j.funbio.2015.02.004. PMID   25986550.
  2. 1 2 Schnabel, Guido; Ash, Joshua; Bryson, Patricia (July 2005). "Identification and characterization of Armillaria tabescens from the southeastern United States". The British Mycological Society. 109 (Pt 11): 1208–1222. doi:10.1017/S0953756205003916. PMID   16279414.
  3. 1 2 3 4 5 6 Lushaj, B. M.; Woodward, S; Keca, N; Intini, M (2009). "Distribution, ecology and host range of Armillaria species in Albania". Forest Pathology. 40 (6): 485–499. doi:10.1111/j.1439-0329.2009.00624.x.
  4. 1 2 3 Tsopelas, P; Tjamos, E (1997). "Occurrence and pathogenicity of Armillaria tabescens on almond in Greece". OEPP/EPPO Bulletin. 27 (4): 455–461. doi:10.1111/j.1365-2338.1997.tb00665.x.
  5. "Armillaria tabescens (armillaria root rot)". www.cabi.org. Retrieved 2017-10-23.
  6. 1 2 3 Shaw, Charles; Kile, Glen (March 1991). Armillaria Root Disease. Forest Service United States Department of Agriculture.
  7. Hasagawa, E; Ota, Y; Hattori, T; Sahashi, N; Kikuchi, T (2011). "Ecology of Armillaria species on conifers in Japan". Forest Pathology. 41 (6): 429–437. doi:10.1111/j.1439-0329.2010.00696.x.
  8. Rishbeth, J (1986). "Some characteristics of English Armillaria species in culture". Mycology Society. 86: 213–218.
  9. 1 2 Rishbeth, J (1991). "Armillaria in an ancient broadleaved woodland". Forest Pathology. 21 (4): 239–249. doi:10.1111/j.1439-0329.1991.tb00975.x.
  10. Mihail, Jeanne; Bruhn, Johann; Leininger, Theodor (June 2002). "The effects of moisture and oxygen availability on Rhizomorph generation by Armillaria tabescens in comparison with A. gallica and A. mellea". Mycology Research. 106 (6): 697–704. doi:10.1017/S0953756202005920.
  11. Miller Jr., Orson K.; Miller, Hope H. (2006). North American Mushrooms: A Field Guide to Edible and Inedible Fungi. Guilford, CN: FalconGuide. p. 151. ISBN   978-0-7627-3109-1.
  12. Phillips, Roger (2010). Mushrooms and Other Fungi of North America . Buffalo, NY: Firefly Books. p.  42. ISBN   978-1-55407-651-2.