The caps may be laterally attached (with no stipe). If there is a stipe, it is normally eccentric and the gills are
decurrent along it. The term pleurotoid is used for any mushroom with this general shape.[4]
The spores are smooth and elongated (described as "cylindrical"). Where
hyphae meet, they are joined by
clamp connections. Pleurotus is not considered to be a
bracket fungus, and most of the species are
monomitic (with a soft consistency). However, remarkably, P. dryinus can sometimes be
dimitic, meaning that it has additional skeletal hyphae, which give it a tougher consistency like bracket fungi.[5]
The classification of species within the genus Pleurotus is difficult due to high
phenotypic variability across wide geographic ranges, geographic overlap of species, and ongoing evolution and
speciation. Early
taxonomic efforts placed the oyster mushrooms within a very broad Agaricus as Agaricus ostreatus (
Jacq. 1774).
Paul Kummer defined the genus Pleurotus in 1871; since then, the genus has been narrowed with some species reclassified to other genera, such as Favolaschia, Hohenbuehelia, Lentinus, Marasmiellus, Omphalotus, Panellus, Pleurocybella, and Resupinatus. See Singer (1986)[7] for an example of Pleurotustaxonomy based on
morphological characteristics.
Phylogeny
More recently, molecular
phylogenetics has been utilized to determine
genetic and
evolutionary relationships between groups within the genus, delineating discrete
clades.[8][9][10]Pleurotus, along with the closely related genus Hohenbuehelia, has been shown to be
monophyletic.[11] 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.[9][12] Many binomial names used in literature are now being grouped together as
species complexes using this technique, and may change.
Phylogenetic species
The following species list is organized according to 1. phylogenetic clade,[8][10] 2. intersterility group (group number in
Roman numerals) or sub-clade,[9][12] 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.
The genus name Pleurotus literally means side ear in reference to the mushroom caps being laterally attached to the substrate. It is a composite of the Ancient Greek words
πλευρά : pleurá - side, and the stem -oto referring to ears (from
οὖς, ὠτός : ear).
In addition to being
saprotrophic, all species of Pleurotus are also
nematophagous, catching
nematodes by paralyzing them with a toxin.[20][11] In the case of the carnivorous mushroom Pleurotus ostreatus, it was shown that small, fragile lollipop-shaped structures (toxocysts) on fungal hyphae contain a volatile ketone, 3-octanone, which disrupts the cell membrane integrity of nematodes, leading to rapid cell and organismal death, hypothetically either to defend themselves and/or to acquire nutrients.[21]
Uses
Culinary
Oyster mushrooms are popular for cooking, torn up instead or sliced, especially in
stir fry or
sauté, because they are consistently thin, and so will cook more evenly than uncut mushrooms of other types.[22] They are often used in
vegetarian cuisine.[23]
The 2007
Cosco Busan oil spill was remediated partly by using 1000 mats of human hair collected from Bay Area salons woven into mats, then used to grow oyster mushrooms, helping to absorb the oil.[24]
After the 2017
Tubbs Fire in California, oyster mushrooms were grown to help remediate toxic ash run-off.[25]
^
abCohen, R.; Persky, L.; Hadar, Y. (2002). "Biotechnological applications and potential of wood-degrading mushrooms of the genus Pleurotus". Applied Microbiology and Biotechnology. 58 (5): 582–94.
doi:
10.1007/s00253-002-0930-y.
PMID11956739.
S2CID45444911.
^Marcel Bon (1987). The Mushrooms and Toadstools of Britain and North-Western Europe. Hodder & Stoughton.
ISBN0-340-39935-X.
^Knudsen, Henning; Jan Vesterhout (2008). Funga Nordica. Copenhagen: Nordsvamp. p. 321.
^
abcdefghVilgalys, R.; Moncalvo, J.M.; Liou, S.R.; Volovsek, M. (1996).
"Recent advances in molecular systematics of the genus Pleurotus"(PDF). In Royse, D.J. (ed.). Mushroom biology and mushroom products: proceedings of the 2nd International Conference, June 9–12, 1996. University Park, PA (USA): Pennsylvania State University: World Society for Mushroom Biology and Mushroom Products. pp. 91–101. Archived from
the original(PDF) on 2011-09-02. Retrieved 2011-03-10.
^
abThorn, R. Greg; Moncalvo, Jean-Marc; Reddy, C. A.; Vilgalys, Rytas (Mar–Apr 2000). "Phylogenetic Analyses and the Distribution of Nematophagy Support a Monophyletic Pleurotaceae within the Polyphyletic Pleurotoid-Lentinoid Fungi". Mycologia. 92 (2): 241–252.
doi:
10.2307/3761557.
JSTOR3761557.
^
abcdefPeterson, Ronald H.; Hughes, Karen W. & Psurtseva, Nadezhda.
"Biological Species in Pleurotus". The University of Tennessee-Knoxville. Archived from
the original on 2011-03-02. Retrieved 2011-03-11.
^
abcdefSegedin, BP; Buchanan, PK; Wilkie, JP (1995). "Studies in the agaricales of New Zealand: New species, new records and renamed species of Pleurotus (Pleurotaceae)". Australian Systematic Botany. 8 (3): 453–482.
doi:
10.1071/SB9950453.
^Alma E. Rodriguez Estrada, Maria del Mar Jimenez-Gasco and Daniel J. Royse (May–June 2010). "Pleurotus eryngii species complex: Sequence analysis and phylogeny based on partial EF1α and RPB2 genes". Fungal Biology. 114 (5–6): 421–428.
doi:
10.1016/j.funbio.2010.03.003.
PMID20943152.
^
abHibbett, D. S.; Thorn, R. G. (Sep–Oct 1994). "Nematode-Trapping in Pleurotus tuberregium". Mycologia. 86 (5): 696–699.
doi:
10.2307/3760542.
JSTOR3760542.
^Freedman, Louise (1987).
"Oyster Mushroom". Wild About Mushrooms: The Cookbook of the Mycological Society of San Francisco. Addison-Wesley.
ISBN9780943186306. Retrieved 29 February 2020.