Basidiomycota
Basidiomycota is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya within the kingdom Fungi. More Basidiomycota includes these groups: mushrooms, stinkhorns, bracket fungi, other polypores, jelly fungi, chanterelles, earth stars, bunts, mirror yeasts, the human pathogenic yeast Cryptococcus. Basidiomycota are filamentous fungi composed of hyphae and reproduce sexually via the formation of specialized club-shaped end cells called basidia that bear external meiospores; these specialized spores are called basidiospores. However, some Basidiomycota reproduce asexually in exclusively. Basidiomycota that reproduce asexually can be recognized as members of this division by gross similarity to others, by the formation of a distinctive anatomical feature, cell wall components, definitively by phylogenetic molecular analysis of DNA sequence data; the most recent classification adopted by a coalition of 67 mycologists recognizes three subphyla and two other class level taxa outside of these, among the Basidiomycota.
As now classified, the subphyla join and cut across various obsolete taxonomic groups commonly used to describe Basidiomycota. According to a 2008 estimate, Basidiomycota comprise three subphyla 16 classes, 52 orders, 177 families, 1,589 genera, 31,515 species. Traditionally, the Basidiomycota were divided into two classes, now obsolete: Homobasidiomycetes, including true mushrooms Heterobasidiomycetes, including the jelly and smut fungiPreviously the entire Basidiomycota were called Basidiomycetes, an invalid class level name coined in 1959 as a counterpart to the Ascomycetes, when neither of these taxa were recognized as divisions; the terms basidiomycetes and ascomycetes are used loosely to refer to Basidiomycota and Ascomycota. They are abbreviated to "basidios" and "ascos" as mycological slang; the Agaricomycotina include what had been called the Hymenomycetes, the Gasteromycetes, as well as most of the jelly fungi. The three classes in the Agaricomycotina are the Agaricomycetes, the Dacrymycetes, the Tremellomycetes.
The class Wallemiomycetes is not yet placed in a subdivision, but recent genomic evidence suggests that it is a sister group of Agaricomycotina. The Pucciniomycotina include the rust fungi, the insect parasitic/symbiotic genus Septobasidium, a former group of smut fungi, a mixture of odd, infrequently seen, or recognized fungi parasitic on plants; the eight classes in the Pucciniomycotina are Agaricostilbomycetes, Atractiellomycetes, Classiculomycetes, Cryptomycocolacomycetes, Cystobasidiomycetes, Microbotryomycetes and Pucciniomycetes. The Ustilaginomycotina are most of the Exobasidiales; the classes of the Ustilaginomycotina are the Exobasidiomycetes, the Entorrhizomycetes, the Ustilaginomycetes. Unlike animals and plants which have recognizable male and female counterparts, Basidiomycota tend to have mutually indistinguishable, compatible haploids which are mycelia being composed of filamentous hyphae. Haploid Basidiomycota mycelia fuse via plasmogamy and the compatible nuclei migrate into each other's mycelia and pair up with the resident nuclei.
Karyogamy is delayed, called a dikaryon. The hyphae are said to be dikaryotic. Conversely, the haploid mycelia are called monokaryons; the dikaryotic mycelium is more vigorous than the individual monokaryotic mycelia, proceeds to take over the substrate in which they are growing. The dikaryons can be decades, or centuries; the monokaryons are neither female. They have either a tetrapolar mating system; this results in the fact that following meiosis, the resulting haploid basidiospores and resultant monokaryons, have nuclei that are compatible with 50% or 25% of their sister basidiospores because the mating genes must differ for them to be compatible. However, there are sometimes more than two possible alleles for a given locus, in such species, depending on the specifics, over 90% of monokaryons could be compatible with each other; the maintenance of the dikaryotic status in dikaryons in many Basidiomycota is facilitated by the formation of clamp connections that physically appear to help coordinate and re-establish pairs of compatible nuclei following synchronous mitotic nuclear divisions.
Variations are multiple. In a typical Basidiomycota lifecycle the long lasting dikaryons periodically produce basidia, the specialized club-shaped end cells, in which a pair of compatible nuclei fuse to form a diploid cell. Meiosis follows shortly with the production of 4 haploid nuclei that migrate into 4 external apical basidiospores. Variations occur, however; the basidiospores are ballistic, hence they are sometimes called ballistospores. In most species, the basidiospores disperse and each
Polyporales
The Polyporales are an order of about 1800 species of fungi in the division Basidiomycota. The order includes some polypores as well as a few agarics. Many species within the order are saprotrophic; some genera, such as Ganoderma and Fomes, contain species that attack living tissues and continue to degrade the wood of their dead hosts. Those of economic importance include several important pathogens of forest and amenity trees and a few species that cause damage by rotting structural timber; some of the Polyporales are commercially cultivated and marketed for use as food items or in traditional Chinese medicine. The order was proposed in 1926 by German mycologist Ernst Albert Gäumann to accommodate species within the phylum Basidiomycota producing basidiocarps showing a gymnocarpous mode of development; as such, the order included the ten families Brachybasidiaceae, Clavariaceae, Dictyolaceae, Polyporaceae, Radulaceae and Vuilleminiaceae, representing a mix of poroid, corticioid and clavarioid fungi.
In a series of publications in 1932, E. J. H. Corner explained the occurrence of different types of hyphae in the fruit bodies of polypore fungi, he introduced the concept of hyphal analysis, which become a fundamental character in polypore taxonomy. The order Polyporales was not adopted by Gäumann's contemporaries; when an attempt was made to introduce a more natural, morphology-based classification of the fungi in the 1980s and 1990s, the order was still overlooked. A standard 1995 reference work placed most polypores and corticioid fungi in the Ganodermatales and Stereales. Molecular research, based on cladistic analysis of DNA sequences, has resurrected and redefined the Polyporales. Studies using a combination of rRNA gene sequences, single-copy protein-coding genes, genome-based phylogenetic analyses have shown that the Polyporales are a monophyletic group, they have not been assigned to a subclass. Though the precise boundaries of the order and its constituent families are yet to be resolved, it retains the core group of polypores in the family Polyporaceae, with additional species in the Fomitopsidaceae and Meripilaceae.
It includes polypores in the Ganodermataceae, which were assigned to their own separate order, the Ganodermatales, based on their distinctive basidiospore morphology. Corticioid fungi belonging to the Cystostereaceae, Phanerochaetaceae, Xenasmataceae are included, as are the cauliflower fungi in the Sparassidaceae. In an extensive molecular analysis, Manfred Binder and colleagues analyzed 6 genes from 373 species and confirmed the existence of four recognized lineages of Polyporales: the antrodia, core polyporoid and residual polyporoid clades. Extending this work, Alfredo Justo and colleagues proposed a phylogenetic overview of the Polyporales that included a new family-level classification, they assigned family names to four informal unranked clades. The families are listed below, followed by their taxonomic authorities and year of publication: Phanerochaetaceae Jülich Irpicaceae Spirin & Zmitr. Meruliaceae Rea Steccherinaceae Parmasto Cerrenaceae Miettinen, Justo & Hibbett 2017) Panaceae Miettinen, Justo & Hibbett Hyphodermataceae Jülich Meripilaceae Jülich Podoscyphaceae D.
A. Reid Polyporaceae Corda Fomitopsidaceae Jülich Laetiporaceae Jülich Dacryobolaceae Jülich Sparassidaceae Jülich Grifolaceae Jülich Gelatoporiaceae Miettinen, Justo & Hibbett Incrustoporiaceae Jülich Ischnodermataceae Jülich Other families that putatively belong to the Polyporales, but for which molecular confirmation is absent or lacking, include Diachanthodaceae Jülich,. C. Dai, B. K. Cui & C. L. Zhao; the Nigrofomitaceae placed in the Polyporales, was shown to be nested as a distinct lineage within the Hymenochaetales. The family Steccherinaceae was redefined in 2012 to contain most species of the poroid and hydnoid genera Antrodiella and Steccherinum, as well as members of 12 other hydnoid and poroid genera, traditionally classified in the families Phanerochaetaceae and Meruliaceae. Several new genera were added to the Steccherinaceae in 2016–17; the order is cosmopolitan and contains around 1800 species of fungi worldwide—about 1.5% of all known fungus species. All species in the Polyporales are saprotrophs.
Their fruit bodies are therefore found on living or moribund trees or on dead attached or fallen wood. Polyporales species that fruit on the ground are either root rot species–such as Laetiporus cincinnatus and Grifola frondosa, or are fruiting from buried pieces of substrate–such as Polyporus radicatus and P. melanopus. Wood-decay Polyporales reduce the volume of dead wood in the forest and are an important component of the carbon cycle. Wood is composed of three types of tissue: lignin and hemicelluloses. White rot species of Polyporales are efficient degraders of the decay-resistant polymer lignin, leaving degraded cellulose as a residue. Brown rot species break down the cellulose fibres, leaving a brown lignin residue. Brown-rot residues such as humus can remain in the
Polypore
Polypores are a group of fungi that form fruiting bodies with pores or tubes on the underside. They are a morphological group of basidiomycetes like gilled mushrooms and hydnoid fungi, not all polypores are related to each other. Polypores are called bracket fungi, their woody fruiting bodies are called conks. Most polypores inhabit tree trunks or branches consuming the wood, but some soil-inhabiting species form mycorrhiza with trees. Polypores and their relatives corticioid. Thus, they play a significant role in nutrient cycling and carbon dioxide production of forest ecosystems. Over one thousand polypore species have been described to science, but a large part of the diversity is still unknown in well-studied temperate areas. Polypores are much more diverse in old natural forests with abundant dead wood than in younger managed forests or plantations. A number of species have declined drastically and are under threat of extinction due to logging and deforestation. Polypores are used in traditional medicine, they are studied for their medicinal value and various industrial applications.
Several polypore species are serious pathogens of plantation trees and are major causes of timber spoilage. Bracket fungi, or shelf fungi, are among the many groups of fungi that compose the division Basidiomycota. Characteristically, they produce shelf- or bracket-shaped or circular fruiting bodies called conks that lie in a close planar grouping of separate or interconnected horizontal rows. Brackets can range from only a single row of a few caps, to dozens of rows of caps that can weigh several hundred pounds, they are found on trees and coarse woody debris, may resemble mushrooms. Some grow larger year after year. Bracket fungi are tough and sturdy and produce their spores, called basidiospores, within the pores that make up the undersurface; because bracket fungi are defined by their growth form rather than phylogeny, the group contains members of multiple clades. Although the term classically was reserved for polypores, molecular studies have revealed some odd relationships; the beefsteak fungus, a well-known bracket fungus, is a member of the agarics.
Other examples of bracket fungi include the sulphur shelf, birch bracket, dryad's saddle, artist's conk, turkey tail. The name polypores is used for a group that includes many of the hard or leathery fungi, which lack a stipe, growing straight out of wood. "Polypore" is derived from the Greek words poly, meaning "much" or "many", poros, meaning "pore". The group includes many different shapes and forms that are common in the tropical forests, including the hard'cup fungi' and the'shell','plate' and'bracket' fungus found growing off logs and still standing dead trees; the fungal individual that develops the fruit bodies that are identified as polypores resides in soil or wood as mycelium. Polypores are restricted to either deciduous or conifer host trees; some species depend on a single tree genus. Forms of polypore fruit bodies range from mushroom-shaped to thin effused patches that develop on dead wood. Perennial fruit bodies of some species growing on living trees can grow over 80 years old.
Most species of polypores develop new, short-lived fruit bodies annually or several times every year. Abundant fruit takes place during the rainy season. Structure of the fruit bodies is simple. Effused or resupinate fruit bodies consist of two layers - a tube layer of vertically arranged tubes that open downwards, supporting layer called subiculum that supports and attached the tubes to substrate. In fruit bodies with a cap the tissue between upper surface and the pore layer is called context. A few polypores have a core between context and substrate. A minority of polypores have a stalk that attach to the cap either laterally or centrally depending on the species. Polypore tubes are a honey-comb-like structure, their sides are covered with the hymenium. The tubes offer shelter for developing spores and help to increase the area of the spore-producing surface. Pore size and shape vary a lot between species, but little within a species – some Hexagonia spp. have 5 mm wide pores whereas pores of Antrodiella spp. are invisible to naked eye with 15 pores per mm.
The larger the pores, the larger the spores. A few polypores produce asexual spores in the upper surface of their cap or without the presence of a sexual fruit body. Bracket fungi grow in semi-circular shapes, looking like trees or wood, they can be saprotrophic, or both. One of the more common genera, can grow large thick shelves that may contribute to the death of the tree, feed off the wood for years after, their hardiness means they are resilient and can live for quite a long time, with many species developing beautiful multi-coloured circles of colour that are annual growth rings. Polypores are among the most efficient decomposers of lignin and cellulose, the main components of wood. Due to this ability they dominate communities of wood-rotting organisms in land ecosystems along with corticioid fungi. Through decomposing tree trunks they recycle a major part of nutrients in f
Ganodermataceae
The Ganodermataceae are a family of fungi in the order Polyporales. As of April 2018, Index Fungorum accepts 8 genera and 300 species in the family; the family was circumscribed by Dutch mycologist Marinus Anton Donk in 1948 to contain polypores with a double spore wall. The inner wall is verruculose to ornamented and coloured, while the outer wall is thin and hyaline. Moncalvo, Jean-Marc. A Nomenclatural Study of the Ganodermataceae. Synopsis Fungorum. Oslo, Norway: Fungiflora. ISBN 8290724187
Elaeis
Elaeis is a genus of palms containing two species, called oil palms. They are used in commercial agriculture in the production of palm oil; the African oil palm Elaeis. It is native to southwest Africa, occurring between Angola and Gambia; the American oil palm Elaeis oleifera is native to tropical Central and South America, is used locally for oil production. Mature palms are single-stemmed, can grow well over 20 m tall; the leaves are pinnate, reach between 3–5 m long. The flowers are produced in dense clusters; the palm fruit is reddish, about the size of a large plum, grows in large bunches. Each fruit is made up of an oily, fleshy outer layer, with a single seed rich in oil; the two species, E. guineensis and E. oleifera can produce fertile hybrids. The genome of E. guineensis has been sequenced, which has important implications for breeding improved strains of the crop plants. Since palm oil contains more saturated fats than oils made from canola, linseed, soybeans and sunflowers, it can withstand extreme deep-frying heat and resists oxidation.
It contains no trans fat, its use in food has increased as food-labelling laws have changed to specify trans fat content. Oil from Elaeis guineensis is used as biofuel. Human use of oil palms may date back to about 5,000 years in coastal west Africa. Palm oil was discovered in the late 19th century by archaeologists in a tomb at Abydos dating back to 3000 BCE, it is thought. Elaeis guineensis is now extensively cultivated in tropical countries outside Africa Malaysia and Indonesia which together produce most of the world supply. Palm oil is considered the most controversial of the cooking oils - for both health and environmental reasons. Palm oil plantations are under increasing scrutiny for social and environmental harm because rainforests with high biodiversity are destroyed, greenhouse gas output is increased, because people are displaced by unscrupulous palm-oil enterprises and traditional livelihoods are negatively impacted. In Indonesia, there is growing pressure for palm oil producers to prove that they are not harming rare animals in the cultivation process.
In 2018 a Christmas TV advertisement by supermarket chain Iceland, produced by Greenpeace, was banned by the UK advertising watchdog Clearcast. Iceland had committed to banning palm oil from its own-brand products by the end of 2018. Attalea maripa, another oil-producing palm Journal of Oil Palm Research Energy and the environment List of Arecaceae genera Social and environmental impact of palm oil
Ancient Greek
The Ancient Greek language includes the forms of Greek used in Ancient Greece and the ancient world from around the 9th century BCE to the 6th century CE. It is roughly divided into the Archaic period, Classical period, Hellenistic period, it is succeeded by medieval Greek. Koine is regarded as a separate historical stage of its own, although in its earliest form it resembled Attic Greek and in its latest form it approaches Medieval Greek. Prior to the Koine period, Greek of the classic and earlier periods included several regional dialects. Ancient Greek was the language of Homer and of fifth-century Athenian historians and philosophers, it has contributed many words to English vocabulary and has been a standard subject of study in educational institutions of the Western world since the Renaissance. This article contains information about the Epic and Classical periods of the language. Ancient Greek was a pluricentric language, divided into many dialects; the main dialect groups are Attic and Ionic, Aeolic and Doric, many of them with several subdivisions.
Some dialects are found in standardized literary forms used in literature, while others are attested only in inscriptions. There are several historical forms. Homeric Greek is a literary form of Archaic Greek used in the epic poems, the "Iliad" and "Odyssey", in poems by other authors. Homeric Greek had significant differences in grammar and pronunciation from Classical Attic and other Classical-era dialects; the origins, early form and development of the Hellenic language family are not well understood because of a lack of contemporaneous evidence. Several theories exist about what Hellenic dialect groups may have existed between the divergence of early Greek-like speech from the common Proto-Indo-European language and the Classical period, they differ in some of the detail. The only attested dialect from this period is Mycenaean Greek, but its relationship to the historical dialects and the historical circumstances of the times imply that the overall groups existed in some form. Scholars assume that major Ancient Greek period dialect groups developed not than 1120 BCE, at the time of the Dorian invasion—and that their first appearances as precise alphabetic writing began in the 8th century BCE.
The invasion would not be "Dorian" unless the invaders had some cultural relationship to the historical Dorians. The invasion is known to have displaced population to the Attic-Ionic regions, who regarded themselves as descendants of the population displaced by or contending with the Dorians; the Greeks of this period believed there were three major divisions of all Greek people—Dorians and Ionians, each with their own defining and distinctive dialects. Allowing for their oversight of Arcadian, an obscure mountain dialect, Cypriot, far from the center of Greek scholarship, this division of people and language is quite similar to the results of modern archaeological-linguistic investigation. One standard formulation for the dialects is: West vs. non-west Greek is the strongest marked and earliest division, with non-west in subsets of Ionic-Attic and Aeolic vs. Arcadocypriot, or Aeolic and Arcado-Cypriot vs. Ionic-Attic. Non-west is called East Greek. Arcadocypriot descended more from the Mycenaean Greek of the Bronze Age.
Boeotian had come under a strong Northwest Greek influence, can in some respects be considered a transitional dialect. Thessalian had come under Northwest Greek influence, though to a lesser degree. Pamphylian Greek, spoken in a small area on the southwestern coast of Anatolia and little preserved in inscriptions, may be either a fifth major dialect group, or it is Mycenaean Greek overlaid by Doric, with a non-Greek native influence. Most of the dialect sub-groups listed above had further subdivisions equivalent to a city-state and its surrounding territory, or to an island. Doric notably had several intermediate divisions as well, into Island Doric, Southern Peloponnesus Doric, Northern Peloponnesus Doric; the Lesbian dialect was Aeolic Greek. All the groups were represented by colonies beyond Greece proper as well, these colonies developed local characteristics under the influence of settlers or neighbors speaking different Greek dialects; the dialects outside the Ionic group are known from inscriptions, notable exceptions being: fragments of the works of the poet Sappho from the island of Lesbos, in Aeolian, the poems of the Boeotian poet Pindar and other lyric poets in Doric.
After the conquests of Alexander the Great in the late 4th century BCE, a new international dialect known as Koine or Common Greek developed based on Attic Greek, but with influence from other dialects. This dialect replaced most of the older dialects, although Doric dialect has survived in the Tsakonian language, spoken in the region of modern Sparta. Doric has passed down its aorist terminations into most verbs of Demotic Greek. By about the 6th century CE, the Koine had metamorphosized into Medieval Greek. Ancient Macedonian was an Indo-European language at least related to Greek, but its exact relationship is unclear because of insufficient data: a dialect of Greek; the Macedonian dialect (or l
Wood-decay fungus
A wood-decay fungus is any species of fungus that digests moist wood, causing it to rot. Some species of wood-decay fungi attack dead wood, such as brown rot, some, such as Armillaria, are parasitic and colonize living trees. Excessive moisture above the fibre saturation point in wood is required for fungal colonization and proliferation. Fungi that not only grow on wood but permeate its fibrous structure and cause decay, are called lignicolous fungi. In nature, this process causes the breakdown of complex molecules and leads to the return of nutrients to the soil. Various lignicolous fungi consume wood in various ways; the rate of decay of wooden materials in various climates can be estimated by empirical models. Wood-decay fungi can be classified according to the type of decay; the best-known types are brown rot, soft rot, white rot. Each produce different enzymes, can degrade different plant materials, can colonise different environmental niches; the residual products of decomposition from fungal action have variable pH, solubility and redox potentials.
Over time this residue will become incorporated in the soil and sediment, so can have a noticeable effect on the environment of that area. Brown-rot fungi break down cellulose that form the wood structure. Cellulose is broken down by hydrogen peroxide, produced during the breakdown of hemicellulose; because hydrogen peroxide is a small molecule, it can diffuse through the wood, leading to a decay, not confined to the direct surroundings of the fungal hyphae. As a result of this type of decay, the wood shrinks, shows a brown discoloration, cracks into cubical pieces, a phenomenon termed cubical fracture; the fungi of certain types remove cellulose compounds from wood and hence the wood becomes brown colour. Brown rot in a dry, crumbly condition is sometimes incorrectly referred to as dry rot in general; the term brown rot replaced the general use of the term dry rot, as wood must be damp to decay, although it may become dry later. Dry rot is a generic name for certain species of brown-rot fungi.
Brown-rot fungi of particular economic importance include Serpula lacrymans, Fibroporia vaillantii, Coniophora puteana, which may attack timber in buildings. Other brown-rot fungi include the sulfur shelf, Phaeolus schweinitzii, Fomitopsis pinicola. Brown-rot fungal decay is characterised by extensive demethylation of lignins whereas white-rot tends to produce low yields of molecules with demethylated functional groups. There are few brown rot fungi in tropical climates or in southern temperate zones. Most brown rot fungi have a geographical range north of the Tropic of Cancer, most of these are found north of the 35° latitude, corresponding to a boreal distribution; those brown rot fungi between latitudes 23.5° and 35° are found at high elevations in pine forest regions, or in coniferous forest regions such as the Rocky Mountains or the Himalayas. Soft-rot fungi secrete cellulase from their hyphae, an enzyme that breaks down cellulose in the wood; this leads to the formation of microscopic cavities inside the wood, sometimes to a discoloration and cracking pattern similar to brown rot.
Soft-rot fungi need fixed nitrogen in order to synthesize enzymes, which they obtain either from the wood or from the environment. Examples of soft-rot-causing fungi are Chaetomium and Kretzschmaria deusta. Soft-rot fungi are able to colonise conditions that are too hot, cold or wet for brown or white-rot to inhabit, they can decompose woods with high levels of compounds that are resistant to biological attack. Bark in woody plants contains a high concentration of tannin, difficult for fungi to decompose, suberin which may act as a microbial barrier; the bark acts as form of protection for the more vulnerable interior of the plant. Soft-rot fungi do not tend to be able to decompose matter as as white-rot fungi: they are less aggressive decomposers. White-rot fungi break down the lignin in wood; as a result, the wood changes texture, becoming moist, spongy, or stringy. Because white-rot fungi are able to produce enzymes, such as laccase, needed to break down lignin and other complex organic molecules, they have been investigated for use in mycoremediation applications.
There are many different enzymes that are involved in the decay of wood by white-rot fungi, some of which directly oxidize lignin. The relative abundance of phenylpropane alkyl side chains of lignin characteristically decreases when decayed by white-rot fungi, it has been reported that the oyster mushroom preferentially decays lignin instead of polysaccharides. This is different from some other white-rot fungi, e.g. Phanerochaete chrysosporium, which shows no selectivity to lignocellulose. Honey mushroom is a white-rot fungus notorious for attacking living trees. Pleurotus ostreatus and other oyster mushrooms are cultivated white-rot fungi, but P. ostreatus is not parasitic and will not grow on a living tree, unless it is dying from other causes. Other white-rot fungi include the turkey tail, artist's conk, tinder fungus. White-rot fungi are grown all over the world as a source of food – for example the shiitake mushroom, which in 2003 comprised 25% of total mushroom production. Snag Compartmentalization of decay in trees Schwarze, Francis W. M. R..
Fungal Strategies of Wood Decay in Trees. Springer. ISBN 978-3-540
