Pleurotus
Encyclopedia
Pleurotus is a genus
of gill
ed mushroom
s which includes one of the most widely eaten mushrooms, P. ostreatus. Species of Pleurotus may be called oyster, abalone, or tree mushrooms, and are some of the most commonly cultivated
edible mushroom
s in the world. Pleurotus fungi have been used in mycoremediation
of pollutants such as petroleum
and polycyclic aromatic hydrocarbon
s.
Pleurotus means "side ear", from Greek
πλευρή (pleurē), "side" + ὠτός (ōtos), genitive of οὖς (ous), "ear".
along it. The term pleurotoid
is used for mushrooms having this general shape.
The spores are smooth and elongated (described as "cylindrical"). Where hypha
e meet, they are joined by clamp connection
s. Pleurotus is not considered to be a bracket fungus
, and most of the species are monomitic (with a soft consistency). However, remarkably, Pleurotus dryinus
can sometimes be dimitic, meaning that it has additional skeletal hyphae, which give it a tougher consistency like bracket fungi.
and temperate climates throughout the world. Most species of Pleurotus are white-rot fungi
on hardwood
trees, although some also decay conifer wood
. P. eryngii is unusual in its association with herbaceous plant
s, and P. tuber-regium produces underground sclerotia
. In addition to being saprotrophic, all species of Pleurotus are also nematophagous
, catching nematode
s by paralyzing them with a toxin.
variability across wide geographic ranges, geographic overlap of species, and ongoing evolution and speciation
. Early taxonomic
efforts placed the oyster mushrooms within Agaricus
(Agaricus ostreatus Jacq.
1774). Paul Kummer
defined the genus Pleurotus in 1871; since then, the genus has been narrowed with species moving to other genera such as Favolaschia
, Hohenbuehelia
, Lentinus
, Marasmiellus
, Omphalotus
, Panellus
, Pleurocybella
, and Resupinatus
. See Singer (1986) for an example of Pleurotus taxonomy
based on morphological
characteristics.
has been utilized to determine genetic
and evolution
ary relationships between groups within the genus, delineating discrete clade
s. Pleurotus, along with the closely related genus Hohenbuehelia
, has been shown to be monophyletic
. Tests of cross-breeding viability between groups have been used to further define which groups are deserving of species
rank, as opposed to subspecies
, variety, or synonymy
. If two groups of morphologically distinct Pleurotus fungi are able to cross-breed and produce fertile offspring, they meet one definition of species
. These reproductively discrete groups, referred to as intersterility groups, have begun to be defined in Pleurotus. Many binomial names used in literature are now being grouped together as species complex
es using this technique, and may change.
) or sub-clade, and then 3. any older binomial names that have been found to be closely related, reproductively compatible, or synonymous, although they may no longer be taxonomically valid. This list is likely to be incomplete.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of gill
Gill (mushroom)
A lamella, or gill, is a papery hymenophore rib under the cap of some mushroom species, most often but not always agarics. The gills are used by the mushrooms as a means of spore dispersal, and are important for species identification...
ed mushroom
Mushroom
A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...
s which includes one of the most widely eaten mushrooms, P. ostreatus. Species of Pleurotus may be called oyster, abalone, or tree mushrooms, and are some of the most commonly cultivated
Fungiculture
Fungiculture is the process of producing food, medicine, and other products by the cultivation of mushrooms and other fungi.The word is also commonly used to refer to the practice of cultivating fungi by leafcutter ants, termites, ambrosia beetles, and marsh periwinkles.- Introduction :Mushrooms...
edible mushroom
Edible mushroom
Edible mushrooms are the fleshy and edible fruiting bodies of several species of fungi. Mushrooms belong to the macrofungi, because their fruiting structures are large enough to be seen with the naked eye. They can appear either below ground or above ground where they may be picked by hand...
s in the world. Pleurotus fungi have been used in mycoremediation
Mycoremediation
Mycoremediation, a phrase coined by Paul Stamets, is a form of bioremediation, the process of using fungi to degrade or sequester contaminants in the environment. Stimulating microbial and enzyme activity, mycelium reduces toxins in-situ...
of pollutants such as petroleum
Petroleum
Petroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...
and polycyclic aromatic hydrocarbon
Polycyclic aromatic hydrocarbon
Polycyclic aromatic hydrocarbons , also known as poly-aromatic hydrocarbons or polynuclear aromatic hydrocarbons, are potent atmospheric pollutants that consist of fused aromatic rings and do not contain heteroatoms or carry substituents. Naphthalene is the simplest example of a PAH...
s.
Pleurotus means "side ear", from Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
πλευρή (pleurē), "side" + ὠτός (ōtos), genitive of οὖς (ous), "ear".
Description
The caps may be laterally attached (with no stem). If there is a stem, it is normally eccentric and the gills are decurrentDecurrent
Decurrent is a term used in botany and mycology to describe plant or fungal parts that extend downward.In botany, the term is most often applied to leaf blades that partly wrap or have wings around the stem or petiole and extend down along the stem...
along it. The term pleurotoid
Pleurotoid fungi
Gilled fungi with laterally-attached fruiting bodies are said to be pleurotoid . Pleurotoid fungi are typically wood-decay fungi and are found on dead and dying trees and coarse woody debris...
is used for mushrooms having this general shape.
The spores are smooth and elongated (described as "cylindrical"). Where hypha
Hypha
A hypha is a long, branching filamentous structure of a fungus, and also of unrelated Actinobacteria. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium; yeasts are unicellular fungi that do not grow as hyphae.-Structure:A hypha consists of one or...
e meet, they are joined by clamp connection
Clamp connection
A clamp connection is a structure formed by growing hyphal cells of certain fungi. It is created to ensure each septum, or segment of hypha separated by crossed walls, receives a set of differing nuclei, which are obtained through mating of hyphae of differing sexual types...
s. Pleurotus is not considered to be a bracket fungus
Bracket fungus
Bracket fungi, or shelf fungi, among many groups of the fungi in the phylum Basidiomycota. Characteristically, they produce shelf- or bracket-shaped fruiting bodies called conks that lie in a close planar grouping of separate or interconnected horizontal rows...
, and most of the species are monomitic (with a soft consistency). However, remarkably, Pleurotus dryinus
Pleurotus dryinus
Pleurotus dryinus is a species of fungus in the Pleurotaceae family. It is a plant pathogen.- External links :* at Index Fungorum...
can sometimes be dimitic, meaning that it has additional skeletal hyphae, which give it a tougher consistency like bracket fungi.
Ecology
Pleurotus fungi are found in both tropicalTropical climate
A tropical climate is a climate of the tropics. In the Köppen climate classification it is a non-arid climate in which all twelve months have mean temperatures above...
and temperate climates throughout the world. Most species of Pleurotus are white-rot fungi
Wood-decay fungus
A wood-decay fungus is a variety of fungus that digests moist wood, causing it to rot. Some wood-decay fungi attack dead wood, such as brown rot, and some, such as Armillaria , are parasitic and colonize living trees. Fungi that not only grow on wood but actually cause it to decay, are called...
on hardwood
Hardwood
Hardwood is wood from angiosperm trees . It may also be used for those trees themselves: these are usually broad-leaved; in temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen.Hardwood contrasts with softwood...
trees, although some also decay conifer wood
Softwood
The term softwood is used to describe wood from trees that are known as gymnosperms.Conifers are an example. It may also be used to describe trees, which tend to be evergreen, notable exceptions being bald cypress and the larches....
. P. eryngii is unusual in its association with herbaceous plant
Herbaceous plant
A herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level. They have no persistent woody stem above ground...
s, and P. tuber-regium produces underground sclerotia
Sclerotium
A sclerotium is a compact mass of hardened fungal mycelium containing food reserves. One role of sclerotia is to survive environmental extremes. In some higher fungi such as ergot, sclerotia become detached and remain dormant until a favorable opportunity for growth. Other fungi that produce...
. In addition to being saprotrophic, all species of Pleurotus are also nematophagous
Nematophagous fungus
Nematophagous fungi are carnivorous fungi specialized in trapping and digesting nematodes. Around 160 species are known. There exist both species that live inside the nematodes from the beginning and others that catch them mostly with glue traps or in rings, some of which constrict on contact. Some...
, catching nematode
Nematode
The nematodes or roundworms are the most diverse phylum of pseudocoelomates, and one of the most diverse of all animals. Nematode species are very difficult to distinguish; over 28,000 have been described, of which over 16,000 are parasitic. It has been estimated that the total number of nematode...
s by paralyzing them with a toxin.
Taxonomy
The classification of species within the genus Pleurotus is difficult due to high phenotypicPhenotype
A phenotype is an organism's observable characteristics or traits: such as its morphology, development, biochemical or physiological properties, behavior, and products of behavior...
variability across wide geographic ranges, geographic overlap of species, and ongoing evolution and speciation
Speciation
Speciation is the evolutionary process by which new biological species arise. The biologist Orator F. Cook seems to have been the first to coin the term 'speciation' for the splitting of lineages or 'cladogenesis,' as opposed to 'anagenesis' or 'phyletic evolution' occurring within lineages...
. Early taxonomic
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
efforts placed the oyster mushrooms within Agaricus
Agaricus
Agaricus is a large and important genus of mushrooms containing both edible and poisonous species, with possibly over 300 members worldwide...
(Agaricus ostreatus Jacq.
Nikolaus Joseph von Jacquin
Nikolaus Joseph Freiherr von Jacquin or Baron Nikolaus von Jacquin. was a scientist who studied medicine, chemistry and botany....
1774). Paul Kummer
Paul Kummer
Paul Kummer was a priest, teacher, and scientist in Zerbst, Germany, known chiefly for his contribution to mycological nomenclature. Earlier classification of agarics by pioneering fungal taxonomist Elias Magnus Fries designated only a very small number of genera, with most species falling into...
defined the genus Pleurotus in 1871; since then, the genus has been narrowed with species moving to other genera such as Favolaschia
Favolaschia
Favolaschia is a genus of fungi in the family Mycenaceae. The genus has a widespread distribution, and contains about 50 species....
, Hohenbuehelia
Hohenbuehelia
Hohenbuehelia is a genus of fungi in the Pleurotaceae family. The genus has a widespread distribution and contains about 50 species.- Species :thumb|right|Hohenbuehelia mastrucata* H. abietina* H. aciculospora* H. amazonica...
, Lentinus
Lentinus
Lentinus is a genus of fungi in the family Polyporaceae. There are 40 species in the genus, which have a widespread distribution, especially in subtropical regions....
, Marasmiellus
Marasmiellus
Marasmiellus is a genus of fungus in the Marasmiaceae family of mushrooms. The widespread genus, circumscribed by American mycologist William Murrill in 1915, contains about 250 species.The name comes from the Greek marasmus meaning wasting....
, Omphalotus
Omphalotus
Omphalotus is a genus of Basidiomycete mushroom formally described by Victor Fayod in 1889. Members have the traditional cap and stem toadstool form. The best known and type species is the jack-o'-lantern mushroom . Species of Omphalotus, which are poisonous, have been mistaken for chanterelles...
, Panellus
Panellus
Panellus is a genus of about 55 species of fungi in the Mycenaceae family.-Description:The fruit bodies of Panellus species are small- to medium-sized, and pleurotoid, meaning they grow on wood, have gills, and usually form semicircular or kidney-shaped caps that may be either directly attached to...
, Pleurocybella
Pleurocybella
Pleurocybella is a genus of fungus in the Marasmiaceae family. The genus is monotypic, containing the single species Pleurocybella porrigens, widespread in temperate forests of the Northern Hemisphere. P. porrigens, known as the angel wing, is a white-rot wood-decay fungus on conifer wood,...
, and Resupinatus
Resupinatus
Resupinatus is a genus of fungi in the family Tricholomataceae. Species are saprobic, and often found growing on the underside of decaying wood. The generic name is derived from the Latin resupin .-Description:...
. See Singer (1986) for an example of Pleurotus taxonomy
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
based on morphological
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
characteristics.
Phylogeny
More recently, molecular phylogeneticsPhylogenetics
In biology, phylogenetics is the study of evolutionary relatedness among groups of organisms , which is discovered through molecular sequencing data and morphological data matrices...
has been utilized to determine genetic
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
and evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
ary relationships between groups within the genus, delineating discrete clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
s. Pleurotus, along with the closely related genus Hohenbuehelia
Hohenbuehelia
Hohenbuehelia is a genus of fungi in the Pleurotaceae family. The genus has a widespread distribution and contains about 50 species.- Species :thumb|right|Hohenbuehelia mastrucata* H. abietina* H. aciculospora* H. amazonica...
, has been shown to be monophyletic
Monophyly
In common cladistic usage, a monophyletic group is a taxon which forms a clade, meaning that it contains all the descendants of the possibly hypothetical closest common ancestor of the members of the group. The term is synonymous with the uncommon term holophyly...
. Tests of cross-breeding viability between groups have been used to further define which groups are deserving of species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
rank, as opposed to subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
, variety, or synonymy
Synonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...
. If two groups of morphologically distinct Pleurotus fungi are able to cross-breed and produce fertile offspring, they meet one definition of species
Species problem
The species problem or species concept is a mixture of difficult, related questions that often come up when biologists identify species and when they define the word "species"....
. These reproductively discrete groups, referred to as intersterility groups, have begun to be defined in Pleurotus. Many binomial names used in literature are now being grouped together as species complex
Species complex
A species complex is a group of closely related species, where the exact demarcation between species is often unclear or cryptic owing to their recent and usually still incomplete reproductive isolation. Ring species, superspecies and cryptic species complex are example of species complex...
es using this technique, and may change.
Phylogenetic species
The following species list is organized according to 1. phylogenetic clade, 2. intersterility group (group number in Roman numeralsRoman numerals
The numeral system of ancient Rome, or Roman numerals, uses combinations of letters from the Latin alphabet to signify values. The numbers 1 to 10 can be expressed in Roman numerals as:...
) or sub-clade, and then 3. any older binomial names that have been found to be closely related, reproductively compatible, or synonymous, although they may no longer be taxonomically valid. This list is likely to be incomplete.
- P. ostreatus clade
- I. P. ostreatus (oyster or pearl oyster mushroom) - North America and northern Eurasia
- P. florida
- II. P. pulmonariusPleurotus pulmonariusCommonly known as the Indian Oyster, Phoenix Mushroom, or the Lung Oyster, Pleurotus pulmonarius is very similar to Pleurotus ostreatus, the pearl oyster, but has a few noticeable differences. The caps of pulmonarius are much paler and smaller than ostreatus and develops more of a stem...
(phoenix or Indian oyster mushroom) - North America, Eurasia, and Australasia- P. columbinus
- P. sapidus
- III. P. populinusPleurotus populinusPleurotus populinus, the aspen oyster mushroom, is a gilled fungus native to North America. It is found on dead wood of aspen and cottonwood trees . Although morphologically similar to Pleurotus ostreatus and Pleurotus pulmonarius, it has been shown to be a distinct species incapable of...
- North America - VI. P. eryngiiPleurotus eryngiiPleurotus eryngii is an edible mushroom native to Mediterranean regions of Europe, the Middle East, and North Africa, but also grown in parts of Asia.In Italian it is called cardoncello; in Chinese, it is called xìng bào gū Pleurotus eryngii (also known as king trumpet mushroom, French horn...
(king oyster mushroom) - Europe and the Middle East- P. ferulae
- P. fossulatus - Afghanistan
- P. nebrodensisPleurotus nebrodensisPleurotus nebrodensis, commonly known as Funcia di basilicu is a fungus that was declared by the IUCN as critically endangered in 2006. This fungus only grows on limestone in northern Sicily in association with Cachrys ferulacea...
- XII. P. abieticola - Asia
- XIII. P. albidus - Caribbean, Central America, South America
- I. P. ostreatus (oyster or pearl oyster mushroom) - North America and northern Eurasia
- P. djamor-cornucopiae clade
- IV. P. cornucopiae (branched oyster mushroom) - Europe
- P. citrinopileatusPleurotus citrinopileatusPleurotus citrinopileatus, the golden oyster mushroom , is an edible gilled fungus. Native to eastern Russia, northern China, and Japan, the golden oyster mushroom is very closely related to P. cornucopiae of Europe, with some authors considering them to be at the rank of subspecies. In far...
(golden oyster mushroom) - eastern Asia - P. euosmus (tarragon oyster mushroom)
- P. citrinopileatus
- V. P. djamorPleurotus djamorPleurotus djamor, commonly known as the pink oyster mushroom, is a species of fungus in the family Pleurotaceae. It was originally named Agaricus djamor by the German-born botanist Georg Eberhard Rumphius, and sanctioned under that name by Elias Magnus Fries in 1821...
(The pink oyster mushroom) - pantropical- P. flabellatus
- P. salmoneo-stramineus
- P. salmonicolor
- XI. P. opuntiae - North America, New Zealand
- XVI. P. calyptratus
- IV. P. cornucopiae (branched oyster mushroom) - Europe
- P. cystidiosus clade
- VII. P. cystidiosus (abalone mushroom) - Global
- P. abalonus - Taiwan
- P. fuscosquamulosus - Africa, Europe
- P. smithii - Mexico
- IX. P. dryinusPleurotus dryinusPleurotus dryinus is a species of fungus in the Pleurotaceae family. It is a plant pathogen.- External links :* at Index Fungorum...
- North America, Europe, and New Zealand
- VII. P. cystidiosus (abalone mushroom) - Global
- VIII. P. levis - subtropical to tropical
- X. P. tuber-regiumPleurotus tuber-regiumPleurotus tuber-regium, the king tuber mushroom, is an edible gilled fungus native to the tropics, including Africa, Asia, and Australasia. It has been shown to be a distinct species incapable of cross-breeding and phylogenetically removed from other species of Pleurotus.P. tuber-regium is a...
(king tuber mushroom) - Africa, Asia, Australasia - XIV. P. australisPleurotus australisPleurotus australis, the brown oyster mushroom, is a gilled fungus native to Australia and New Zealand. It is found on dead wood. Although morphologically similar to some other Pleurotus fungi, it has been shown to be a distinct species incapable of cross-breeding.-External links:* at University...
(brown oyster mushroom) - Australia and New Zealand - XV. P. purpureo-olivaceusPleurotus purpureo-olivaceusPleurotus purpureo-olivaceus is a gilled fungus native to Australia and New Zealand. It is found on dead wood of Nothofagus trees. Although morphologically similar to some other Pleurotus fungi, it has been shown to be a distinct species incapable of cross-breeding and phylogenetically removed...
- Australia and New Zealand- P. rattenburyi
Species of unclear relationship
- P. gardneri
- P. parsonsii
- P. velatus
Former species
- P. sajor-cajuLentinus sajor-cajuLentinus sajor-caju is the common Oyster Mushroom widely cultivated in the Tropics. In India it is mainly grown in Paddy straw, filled into Poly bags and kept in a humid environment....
was moved to the genus LentinusLentinusLentinus is a genus of fungi in the family Polyporaceae. There are 40 species in the genus, which have a widespread distribution, especially in subtropical regions....
. - P. nidiformisOmphalotus nidiformisOmphalotus nidiformis, or ghost fungus, is a gilled basidiomycete mushroom found in southern Australia most notable for its bioluminescent properties. Generally found growing on dead or dying trees, it is saprotroph and parasite....
was moved to the genus OmphalotusOmphalotusOmphalotus is a genus of Basidiomycete mushroom formally described by Victor Fayod in 1889. Members have the traditional cap and stem toadstool form. The best known and type species is the jack-o'-lantern mushroom . Species of Omphalotus, which are poisonous, have been mistaken for chanterelles...
in 1994.
See also
- AntromycopsisAntromycopsisAntromycopsis is a genus of fungi in the Pleurotaceae family. The genus, an anamorphic form of Pleurotus, has a widespread distribution and contains three species....
- an anamorphicTeleomorph, anamorph and holomorphThe terms teleomorph, anamorph, and holomorph apply to portions of the life cycles of fungi in the phyla Ascomycota and Basidiomycota.*Teleomorph: the sexual reproductive stage , typically a fruiting body....
form of Pleurotus
External links
- Pleurotus Genus on the Mushroom, the Journal of Wild Mushrooming site
- Oysters: Pleurotoid Mushrooms at MushroomExpert.com
- Dichotomous key for Pleurotus species from University of Tennessee-Knoxville Mycology Lab
- Oyster Mushroom recipes, Wild About Mushrooms, The Cookbook of the San Francisco Mycological Society, by Louise Freedman