Isaria cicadae | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Fungi |
Division: | Ascomycota |
Class: | Sordariomycetes |
Order: | Hypocreales |
Family: | Cordycipitaceae |
Genus: | Isaria |
Species: | I. cicadae |
Binomial name | |
Isaria cicadae Isaria cicadae Miq., Bull. Sci. phys. nat. Néerl.: 85 (1838) | |
This range map depicts global occurrences of Isaria cicadae and synonymous species including Cordyceps cicadae Shing and Massee, and Paecilomyces cicadae. | |
Synonyms | |
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Isaria cicadae is an ascomycete fungus that parasitizes cicada larvae. [1] It forms white and yellow asexual fruiting structures resembling synnema. [2] While mostly being found throughout Asia in warm, humid regions, it has been found on various other continents. [3] It is known in Traditional Chinese Medicine as Chan Hua and commonly called “cicada flower.” [4] Its medicinal uses date back to the fifth century AD in China. [5] It can also be used in various foods and tonics. [6]
Isaria cicadae is thought to be a cryptic species because of how many different species names have been attributed to it and the controversy over what the correct species name is. I. cicadae was originally described as Isaria cicadae Miq. by Miquel in 1838 until he synonymized it with C. cicadae in 1895. Paecilomyces cicadae was synonymized with C. cicadae in 1974 by Samson. Soon after, S.Z. Shing described the species again as Cordyceps cicadae Shing in 1975, but these are all thought to be generally synonymous. C. cicadae and I. cicadae are both often used in the literature. [3] I. cicadae is thought to be the most current name for the species, although the true taxonomy is still in flux. Other reported synonyms include Cordyceps zhejiangensis [1] , C. sobolifera, C. sinclairii [2] .
Isaria cicadae forms its fruiting structures on the surface of its host, a cicada nymph. [7] The fruiting structure can either cover the entire nymph body or only partially cover it. [3] Sexual structures are not produced on these fruiting structures. [2] Much more information is known about the asexual morph of this fungus because the sexual morph has been reportedly observed once in nature and never in the lab. [3] Its asexual fruiting structures are synnema-like and produce conidiophores and conidia. [2] The fruiting bodies have yellow stalk-looking structures with a white-ish, fluffy tip where the conidiophores are located.
Isaria cicadae is an entomogenous fungi that parasitizes the nymphs of its cicada hosts and forms fruiting structures on the surface. [8] These fruiting structures are produced from June–August, and they protrude from the nymph, up through the soil after the fungus kills it. Asexual means of reproduction occur once temperatures rise following sclerotium development and is done so through conidia, dispersed by air and water. [3] It is said that this fungal species is rare and scarce because it propagates slowly and lacks resistance. [7] This could also be due to the fact that it is largely asexual and clonal in nature, as sexual structures have yet to be reliably observed in lab or in nature. Despite this, there is evidence supporting that it is heterothallic being that a study found a truncated MAT1-1-1 type found in the MAT1-2 locus that is not due to asexual fruiting. [2]
Its genome has been sequenced and found to be 33.9Mb including serine proteases and chintinases which target host tissues and are characteristic of other entomopathogenic fungi. The fungus also produces metabolites such as beauvericins and oosporein which have non-selective insecticidal properties. This would suggest that the fungus could infect more than one host, but this has only been seen in the lab on silkworm pupae and beetle wings. [2]
The life cycle of Cordyceps cicadae (synonymous with I. cicadae) in southern China as observed and described by Zha, Ling-Sheng et al. in 2019 follows. During mid-late summer, conidia of I. cicadae attach to the surface of a cicada nymph’s body within the soil which germinate and form germ tubes that can penetrate below the surface and form hyphae. After two to three days of absorbing the cicada’s nutrients and reproducing, they can occupy the entire body. Hyphae turn to mycelia which cause the nymph to die from absorbing water and nutrients and producing mycotoxins. After the nymph is killed, the fungus forms a sclerotium and produce antibiotics to keep the body from rotting. When temperatures rise again, either that year or the following, mycelia are produced once more to form synnemata that eventually break through the soil to grow above ground. The synnema branches to form multiple conidiophores and chained conidia. The conidia are dispersed by air or water, leading them back to the soil, where they use water flow to infiltrate the soil until they make contact with another nymph and infect. [3]
Isaria cicadae is found in warm, humid, low-elevational regions (below 2,500m), on cicada nymphs in sunny soils. Habitats that fit these criteria include bamboo, broad-leaved, coniferous, and broad-leaved mixed forests. [2] They are mostly found in China, but have also been found throughout Asia, [9] Europe, and North America, [10] with some studies showing other continents as well. [3]
Isaria cicadae/C. cicadae is one of the oldest, most valued and well-known forms of Traditional Chinese Medicine, dating back to the fifth century AD. [5] When used as a medicine, it is referred to as Chan Hua. [11] Many of its medicinal properties relate it to the more commonly used Cordyceps sinensis and Cordyceps militaris , making it a potential substitute for these highly sought after medicinal fungi. [12] Obstacles to using I. cicadae on a larger scale alongside its relatives C. sinensis and C. militaris include its scarcity and its cryptic taxonomy which make it difficult to study, cultivate, and harvest. [13] [2] It has been shown to be helpful for a multitude of health issues and concerns and nonsignificant toxicity has been reported meaning it is thought to be safe to use as treatment. [1] On the other hand, oosporein, which is produced by the fungus, has been shown to cause issues in some species including birds [14] and chickens, [15] canines. [16] Oxalic acid also produced by the fungus could be cause for kidney stone disease in high levels. [17]
Chemicals isolated from I. cicadae/ C. cicadae include nucleotides and nucleosides, sterols (ergosterol, mannitol), cyclic dipeptides, sugars, polysaccharides, fatty acids, amino acids, aromatic compounds, galactomannan, adenosine, uridine, inosine, guanosine, cyclopeptides, myriocin, and inorganic elements. [21] [22] [23] [18] [24] [25]
Botrytis cinerea is a necrotrophic fungus that affects many plant species, although its most notable hosts may be wine grapes. In viticulture, it is commonly known as "botrytis bunch rot"; in horticulture, it is usually called "grey mould" or "gray mold".
Ophiocordyceps sinensis, known colloquially as caterpillar fungus, is an entomopathogenic fungus in the family Ophiocordycipitaceae. It is mainly found in the meadows above 3,500 metres (11,500 ft) on the Tibetan Plateau in Tibet and the Himalayan regions of Bhutan, India, and Nepal. It parasitizes larvae of ghost moths and produces a fruiting body which is valued in traditional Chinese medicine as an aphrodisiac. Caterpillar fungus contains the compound cordycepin, an adenosine derivative. However, the fruiting bodies harvested in nature usually contain high amounts of arsenic and other heavy metals, so they are potentially toxic and sales have been strictly regulated by China's State Administration for Market Regulation since 2016.
Cordyceps is a genus of ascomycete fungi that includes about 600 worldwide species. Diverse variants of cordyceps have had more than 1,500 years of use in Chinese medicine. Most Cordyceps species are endoparasitoids, parasitic mainly on insects and other arthropods ; a few are parasitic on other fungi.
An entomopathogenic fungus is a fungus that can kill or seriously disable insects.
Cordycepin, or 3'-deoxyadenosine, is a derivative of the nucleoside adenosine, differing from the latter by the replacement of the hydroxy group in the 3' position with a hydrogen. It was initially extracted from the fungus Cordyceps militaris, but can now be produced synthetically. It is also found in other Cordyceps species as well as Ophiocordyceps sinensis.
Hyphomycetes are a form classification of fungi, part of what has often been referred to as fungi imperfecti, Deuteromycota, or anamorphic fungi. Hyphomycetes lack closed fruit bodies, and are often referred to as moulds. Most hyphomycetes are now assigned to the Ascomycota, on the basis of genetic connections made by life-cycle studies or by phylogenetic analysis of DNA sequences; many remain unassigned phylogenetically.
Beauveria is a genus of asexually-reproducing fungi allied with the ascomycete family Cordycipitaceae. Its several species are typically insect pathogens. The sexual states (teleomorphs) of Beauveria species, where known, are species of Cordyceps.
Ganoderic acids are a class of closely related triterpenoids found in Ganoderma mushrooms. For thousands of years, the fruiting bodies of Ganoderma fungi have been used in traditional medicines in East Asia. Consequently, there have been efforts to identify the chemical constituents that may be responsible for the putative pharmacological effects. The two most well described ganoderic acids out of the many that have been identified and characterized are ganoderic acids A and B. Some ganoderic acids have been found to possess biological activities including hepatoprotection, anti-tumor effects, and 5-alpha reductase inhibition.
Ustilaginoidea virens, perfect sexual stage Villosiclava virens, is a plant pathogen which causes the disease "false smut" of rice which reduces both grain yield and grain quality. The disease occurs in more than 40 countries, especially in the rice producing countries of Asia. but also in the U.S. As the common name suggests, it is not a true smut (fungus), but an ascomycete. False smut does not replace all or part of the kernel with a mass of black spores, rather sori form erupting through the palea and lemma forming a ball of mycelia, the outermost layers are spore-producing. Infected rice kernels are always destroyed by the disease.
Massospora cicadina is a fungal pathogen that infects only 13 and 17 year periodical cicadas. Infection results in a "plug" of spores that replaces the end of the cicada's abdomen while it is still alive, leading to infertility, disease transmission, and eventual death of the cicada.
Immersaria is a genus of lichen-forming fungi in the family Lecideaceae. It has eight species of crustose lichens.
Isaria sinclairii is a species of entomopathogenic fungus mostly infecting the underground nymphs of cicadas. It produces myriocin, from which the synthetic drug fingolimod, a treatment for multiple sclerosis, was developed.
Purpureocillium lilacinum is a species of filamentous fungus in the family Ophiocordycipitaceae. It has been isolated from a wide range of habitats, including cultivated and uncultivated soils, forests, grassland, deserts, estuarine sediments and sewage sludge, and insects. It has also been found in nematode eggs, and occasionally from females of root-knot and cyst nematodes. In addition, it has frequently been detected in the rhizosphere of many crops. The species can grow at a wide range of temperatures – from 8 to 38 °C for a few isolates, with optimal growth in the range 26 to 30 °C. It also has a wide pH tolerance and can grow on a variety of substrates. P. lilacinum has shown promising results for use as a biocontrol agent to control the growth of destructive root-knot nematodes.
Phillyrin is an endophytic fungal isolate with anti-obesity activity. It can be produced by Colletotrichum gloeosporioides, an endophytic fungus isolated from Forsythia suspensa. It can also be prepared directly from Forsythia suspensa.
Tolypocladium ophioglossoides, also known by two of its better known synonyms Elaphocordyceps ophioglossoides and Cordyceps ophioglossoides and commonly known as the goldenthread cordyceps, is a species of fungus in the family Ophiocordycipitaceae. It is parasitic on fruit bodies of the truffle-like Elaphomyces. The species is considered inedible, but is valued in traditional Chinese medicine.
Cordyceps militaris is a species of fungus in the family Cordycipitaceae, and the type species of the genus Cordyceps, which consists of hundreds of species. The species was originally described by Carl Linnaeus in 1753 as Clavaria militaris. Cordyceps militaris parasitizes insects and is used use in traditional Chinese medicine and modern pharmaceuticals.
Trichothecium roseum is a fungus in the division Ascomycota first reported in 1809. It is characterized by its flat and granular colonies which are initially white and develop to be light pink in color. This fungus reproduces asexually through the formation of conidia with no known sexual state. Trichothecium roseum is distinctive from other species of the genus Trichothecium in its characteristic zigzag patterned chained conidia. It is found in various countries worldwide and can grow in a variety of habitats ranging from leaf litter to fruit crops. Trichothecium roseum produces a wide variety of secondary metabolites including mycotoxins, such as roseotoxins and trichothecenes, which can infect and spoil a variety of fruit crops. It can act as both a secondary and opportunistic pathogen by causing pink rot on various fruits and vegetables and thus has an economical impact on the farming industry. Secondary metabolites of T. roseum, specifically Trichothecinol A, are being investigated as potential anti-metastatic drugs. Several agents including harpin, silicon oxide, and sodium silicate are potential inhibitors of T. roseum growth on fruit crops. Trichothecium roseum is mainly a plant pathogen and has yet to show a significant impact on human health.
Isaria fumosorosea is an entomopathogenic fungus, formerly known as Paecilomyces fumosoroseus. It shows promise as a biological pesticide with an extensive host range.
Cordyceps locustiphila is the basionym and teleomorph of the fungi Beauveria locustiphila, a species of fungus in the family Cordycipitaceae. and is a species within the genus Cordyceps. It was originally described in by Henn in 1904. C. locustiphila is an entomopathogen and obligate parasite of the grasshopper species within the genus Colpolopha or Tropidacris, and as such is endemic to South America. The scientific name is derived from its close relationship with its host, being named after locusts. The fungi was renamed to Beauveria locustiphila in 2017 following research into the family Cordycipitaceae. Following the loss of the species type specimen, new studies were conducted that now recommend that the fungi be divided into 3 species. C. locustiphila, C. diapheromeriphila, and C. acridophila.
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