''Beauveria bassiana'' is a

fungus A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from t ...

that grows naturally in soils throughout the world and acts as a

parasite Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...

on various

arthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and cuticle made of chiti ...

species, causing white muscardine disease; it thus belongs to the

entomopathogenic fungi An entomopathogenic fungus is a fungus that can kill or seriously disable insects. Typical life cycle These fungi usually attach to the external body surface of insects in the form of microscopic spores (usually asexual, mitosporic spores also ...

. It is used as a biological insecticide to control a number of pests, including

termite Termites are small insects that live in colonies and have distinct castes (eusocial) and feed on wood or other dead plant matter. Termites comprise the infraorder Isoptera, or alternatively the epifamily Termitoidae, within the order Blatto ...

thrips Thrips (order Thysanoptera) are minute (mostly long or less), slender insects with fringed wings and unique asymmetrical mouthparts. Different thrips species feed mostly on plants by puncturing and sucking up the contents, although a few are ...

whiteflies Whiteflies are Hemipterans that typically feed on the undersides of plant leaves. They comprise the family Aleyrodidae, the only family in the superfamily Aleyrodoidea. More than 1550 species have been described. Description and taxonomy The ...

aphids Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A t ...

and various beetles. Its use in the control of bedbugs and

malaria Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or death. S ...

-transmitting

mosquito Mosquitoes (or mosquitos) are members of a group of almost 3,600 species of small flies within the family Culicidae (from the Latin ''culex'' meaning " gnat"). The word "mosquito" (formed by ''mosca'' and diminutive ''-ito'') is Spanish for "li ...

s is under investigation.Donald G. McNeil Jr.
Fungus Fatal to Mosquito May Aid Global War on Malaria
''The New York Times'', 10 June 2005

Discovery and name

The species is named after the

Italian Italian(s) may refer to: * Anything of, from, or related to the people of Italy over the centuries ** Italians, an ethnic group or simply a citizen of the Italian Republic or Italian Kingdom ** Italian language, a Romance language *** Regional Ita ...

entomologist

Agostino Bassi Agostino Bassi, sometimes called de Lodi (25 September 1773 – 8 February 1856), was an Italian entomologist. He preceded Louis Pasteur in the discovery that microorganisms can be the cause of disease (the germ theory of disease). He discovered ...

, who discovered it in 1835 as the cause of the muscardine disease which then led to carriers transmitting it by airborne means, and later the same year it was named ''Botrytis bassiana'' by

Giuseppe Gabriel Balsamo-Crivelli Giuseppe Gabriel Balsamo-Crivelli (1 September 1800, in Milan – 15 November 1874, in Pavia) was an Italian naturalist. He became a professor of mineralogy and zoology at the University of Pavia in 1851, and was appointed professor of comp ...

. In 1911 Jean Beauverie did further study and the next year

Jean Paul Vuillemin Jean Paul Vuillemin (13 February 1861 – 25 September 1932 in Malzéville) was a French mycologist born in Docelles. He studied at the University of Nancy, earning his medical doctorate in 1884. In 1892 he obtained his doctorate in sciences at ...

made it the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

of his new ''Beauveria''. It was formerly also known as ''Tritirachium shiotae''. The name ''B. bassiana'' has long been used to describe a

species complex In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

of morphologically similar and closely related

isolates {{About, , the linguistics term dealing with languages unrelated to any other language in the world, Language isolate, other uses, Isolate (disambiguation){{!Isolate Isolates is a term used in developmental psychology and family studies, to describ ...

. Rehner and Buckley have shown that ''B. bassiana'' consists of many distinct lineages that should be recognized as distinct phylogenetic species and the genus ''

Beauveria ''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 o ...

'' was redescribed with a proposed type for ''B. bassiana'' in 2011. In light of this work and the known existence of

cryptic species In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

, it is important to characterise

isolate Isolate may refer to: Arts, entertainment, and media * ''Isolate'' (film), a 2013 Australian film * ''Isolate'' (Circus Maximus album), 2007 * ''Isolate'' (Gary Numan album), 1992 Language * Isolating language, with near-unity morpheme/word ...

s used to develop

biological insecticides A Biopesticide is a biological substance or organism that damages, kills, or repels organisms seens as pests. Biological pest management intervention involves predatory, parasitic, or chemical relationships. They are obtained from organisms inclu ...

Relation to ''Cordyceps'' and other fungi

''Beauveria bassiana'' is the anamorph (asexually reproducing form) of '' Cordyceps bassiana''. The latter

teleomorph In mycology, the 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 (morph), typically a fruiting body. *Anamorph: an asex ...

(the sexually reproducing form) has been collected only in eastern Asia.

White muscardine disease

The

insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three ...

disease caused by the fungus is a

muscardine Muscardine is a disease of insects. It is caused by many species of entomopathogenic fungus. Many muscardines are known for affecting silkworms.Singh, T. ''Principles And Techniques Of Silkworm Seed Production''. Discovery Publishing House. 2004. ...

which has been called white muscardine disease. When the microscopic spores of the fungus come into contact with the body of an insect host, they germinate, penetrate the cuticle, and grow inside, killing the insect within a matter of days. Afterwards, a white mold emerges from the cadaver and produces new spores. A typical isolate of ''B. bassiana'' can attack a broad range of insects; various isolates differ in their host range. The factors responsible for host susceptibility are not known. WhiteMuscardineDiseaseGoldenSilkOrbWeaver

WhiteMuscardineDiseaseGoldenSilkOrbWeaver

''Beauveria bassiana'' parasitizing the

Colorado potato beetle The Colorado potato beetle (''Leptinotarsa decemlineata''), also known as the Colorado beetle, the ten-striped spearman, the ten-lined potato beetle, or the potato bug, is a major pest of potato crops. It is about long, with a bright yellow/o ...

has been reported to be, in turn, the host of a mycoparasitic fungus '' Syspastospora parasitica''. This organism also attacks related insect-pathogenic species of the

Clavicipitaceae The Clavicipitaceae are a family of fungi within the order Hypocreales. A 2008 estimate placed 43 genera in the family, but recent work has increased this number to 97. Phylogeny Molecular phylogenetic analysis of multigene DNA sequence data in ...

Morphology of the fungus

In culture, ''B. bassiana'' grows as a white mould. On most common cultural media, it produces many dry, powdery conidia in distinctive white spore balls. Each spore ball is composed of a cluster of conidiogenous cells. The conidiogenous cells of ''B. bassiana'' are short and ovoid, and terminate in a narrow apical extension called a

rachis In biology, a rachis (from the grc, ῥάχις [], "backbone, spine") is a main axis or "shaft". In zoology and microbiology In vertebrates, ''rachis'' can refer to the series of articulated vertebrae, which encase the spinal cord. In this c ...

. The rachis elongates after each conidium is produced, resulting in a long zig-zag extension. The conidia are single-celled, haploid, and

hydrophobic In chemistry, hydrophobicity is the physical property of a molecule that is seemingly repelled from a mass of water (known as a hydrophobe). In contrast, hydrophiles are attracted to water. Hydrophobic molecules tend to be nonpolar and, t ...

Use in biological control of insects

''Beauveria bassiana'' can be used as a biological insecticide to control a number of pests such as

, and many other insects. Its use in the control of

-transmitting

s is under investigation. As an insecticide, the spores are sprayed on affected crops as an emulsified suspension or wettable powder or applied to mosquito nets as a mosquito control agent. As a species, ''Beauveria bassiana'' parasitizes a very wide range of arthropod hosts. However, different

strain Strain may refer to: Science and technology * Strain (biology), variants of plants, viruses or bacteria; or an inbred animal used for experimental purposes * Strain (chemistry), a chemical stress of a molecule * Strain (injury), an injury to a mu ...

s vary in their host ranges, some having rather narrow ranges, like strain Bba 5653 that is very virulent to the

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...

e of the

diamondback moth The diamondback moth (''Plutella xylostella''), sometimes called the cabbage moth, is a moth species of the family Plutellidae and genus '' Plutella''. The small, grayish-brown moth sometimes has a cream-colored band that forms a diamond along ...

and kills only few other types of

caterpillars Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths). As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder Symp ...

. Some strains do have a wide host range and should, therefore, be considered nonselective biological insecticides. These should not be applied to flowers visited by

pollinating Pollination is the transfer of pollen from an anther of a plant to the stigma of a plant, later enabling fertilisation and the production of seeds, most often by an animal or by wind. Pollinating agents can be animals such as insects, birds, a ...

insects. Known targets include: *

Aphid Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A t ...

s *

Whiteflies Whiteflies are Hemipterans that typically feed on the undersides of plant leaves. They comprise the family Aleyrodidae, the only family in the superfamily Aleyrodoidea. More than 1550 species have been described. Description and taxonomy The ...

Mealybugs Mealybugs are insects in the family Pseudococcidae, unarmored scale insects found in moist, warm habitats. Many species are considered pests as they feed on plant juices of greenhouse plants, house plants and subtropical trees and also act as a ...

Psyllids Psyllidae, the jumping plant lice or psyllids, are a family of small plant-feeding insects that tend to be very host-specific, i.e. each plant-louse species only feeds on one plant species (monophagous) or feeds on a few closely related plants ( ...

** Chinch bug ** Lygus bugs *

Grasshopper Grasshoppers are a group of insects belonging to the suborder Caelifera. They are among what is possibly the most ancient living group of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago. Grasshopp ...

s * Stink bugs (''

Halyomorpha halys The brown marmorated stink bug (''Halyomorpha halys'') is an insect in the family Pentatomidae, native to China, Japan, Korea and other Asian regions. In September 1998 it was collected in Allentown, Pennsylvania, where it is believed to have be ...

'') *

Thrips Thrips ( order Thysanoptera) are minute (mostly long or less), slender insects with fringed wings and unique asymmetrical mouthparts. Different thrips species feed mostly on plants by puncturing and sucking up the contents, although a few are ...

Termite Termites are small insects that live in colonies and have distinct castes (eusocial) and feed on wood or other dead plant matter. Termites comprise the infraorder Isoptera, or alternatively the epifamily Termitoidae, within the order Blattode ...

s *

Fire ant Fire ants are several species of ants in the genus ''Solenopsis'', which includes over 200 species. ''Solenopsis'' are stinging ants, and most of their common names reflect this, for example, ginger ants and tropical fire ants. Many of the nam ...

s *

Flies Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...

* Stem borers ** Fungal gnats ** Shoreflies *

Beetle Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...

s **

Bark beetle A bark beetle is the common name for the subfamily of beetles Scolytinae. Previously, this was considered a distinct family (Scolytidae), but is now understood to be a specialized clade of the "true weevil" family (Curculionidae). Although the ...

Black vine weevil Black vine weevil (''Otiorhynchus sulcatus'') is an insect native to Europe but common in North America as well. It is a pest of many garden plants. Overview The adult weevil is matte black with fused wing covers, and is unable to fly. It feeds ...

Boll weevil The boll weevil (''Anthonomus grandis'') is a beetle that feeds on cotton buds and flowers. Thought to be native to Central Mexico, it migrated into the United States from Mexico in the late 19th century and had infested all U.S. cotton-growing ...

Cereal leaf beetle The cereal leaf beetle (''Oulema melanopus'') is a significant crop pest, described by Carl Linnaeus in 1758. Life history One generation of this beetle is produced a year. Adults feed before winter and spend most of their overwintering time in ...

** Coffee berry borer **

Emerald ash borer The emerald ash borer (''Agrilus planipennis''), also known by the acronym EAB, is a green buprestid or jewel beetle native to north-eastern Asia that feeds on ash species. Females lay eggs in bark crevices on ash trees, and larvae feed undern ...

(in conjunction with the

parasitoid In evolutionary ecology, a parasitoid is an organism that lives in close association with its host (biology), host at the host's expense, eventually resulting in the death of the host. Parasitoidism is one of six major evolutionarily stable str ...

wasp ''

Tetrastichus planipennisi ''Tetrastichus planipennisi'' is a parasitic non-stinging wasp of the family Eulophidae which is native to North Asia. It is a parasitoid of the emerald ash borer (''Agrilus planipennis'' Fairmaire, family Buprestidae), an invasive species which ...

'') **

Japanese beetle The Japanese beetle (''Popillia japonica'') is a species of scarab beetle. The adult measures in length and in width, has iridescent copper-colored elytra and a green thorax and head. It is not very destructive in Japan (where it is control ...

Mexican bean beetle The Mexican bean beetle (''Epilachna varivestis'') is a species of lady beetle that can be an agricultural pest. It is one of the few North American lady beetles that feed on plants rather than other insects. It is found throughout Mexico and ...

** Red palm weevil ** Strawberry root weevil *

Caterpillar Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths). As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder Sym ...

s **

Codling moth The codling moth (''Cydia pomonella'') is a member of the Lepidopteran family Tortricidae. They are major pests to agricultural crops, mainly fruits such as apples and pears. Because the larvae are not able to feed on leaves, they are highly d ...

** Douglas fir tussock moth **

European corn borer The European corn borer (''Ostrinia nubilalis''), also known as the European corn worm or European high-flyer, is a moth of the family Crambidae which includes other grass moths. It is a pest of grain, particularly maize (''Zea mays''). The in ...

** Invasive silkworms ** Apple clearwing moth *

Mite Mites are small arachnids (eight-legged arthropods). Mites span two large orders of arachnids, the Acariformes and the Parasitiformes, which were historically grouped together in the subclass Acari, but genetic analysis does not show clear evid ...

s The fungus rarely infects humans or other animals, so it is generally considered safe as an insecticide. However, at least one case of human infection by ''B. bassiana'' has been reported in a person with a suppressed immune system. Additionally, the spores may exacerbate

breathing difficulties Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing di ...

. Wagner and Lewis reported the ability of ''B. bassiana'' to grow as an

endophyte An endophyte is an endosymbiont, often a bacterium or fungus, that lives within a plant for at least part of its life cycle without causing apparent disease. Endophytes are ubiquitous and have been found in all species of plants studied to date; h ...

in corn. A fungus attributed to be ''B. bassiana'' was observed to cause infections in a captive

American alligator The American alligator (''Alligator mississippiensis''), sometimes referred to colloquially as a gator or common alligator, is a large crocodilian reptile native to the Southeastern United States. It is one of the two extant species in the g ...

and ''B. bassiana'' was implicated in causing a

pulmonary disease Respiratory diseases, or lung diseases, are pathological conditions affecting the organs and tissues that make gas exchange difficult in air-breathing animals. They include conditions of the respiratory tract including the trachea, bronchi, bron ...

in captive tortoises. The

reptile Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians ( ...

s were in captivity and under temperature stress which may explain their susceptibility to the fungus. When a

tortoise Tortoises () are reptiles of the family Testudinidae of the order Testudines (Latin: ''tortoise''). Like other turtles, tortoises have a turtle shell, shell to protect from predation and other threats. The shell in tortoises is generally hard, ...

was kept at 22°C and injected with 0.5 mL of 106 spores of ''B. bassiana'' into the lung, no mortality was observed, while a second contaminated tortoise died when kept only at 16°C. Preliminary research has shown the fungus is 100% effective in eliminating bed bugs exposed to cotton fabric sprayed with fungus spores. It is also effective against bed bug colonies due to ''B. bassiana'' carried by infected bugs back to their harborages. The tested strain of B bassiana caused rapid mortality (3 - 5 days) after short-term exposure. In a 2017 follow-up study,

pyrethroid A pyrethroid is an organic compound similar to the natural pyrethrins, which are produced by the flowers of pyrethrums (''Chrysanthemum cinerariaefolium'' and ''Chrysanthemum coccineum, C. coccineum''). Pyrethroids are used as commercial and hou ...

-resistant bed bugs had >94% mortality after treatment with a commercial preparation of B. bassiana. A microevolutionary experiment in 2013 showed that the Greater wax moth (''

Galleria mellonella ''Galleria mellonella'', the greater wax moth or honeycomb moth, is a moth of the family Pyralidae. ''G. mellonella'' is found throughout the world. It is one of two species of wax moths, with the other being the lesser wax moth. ''G. mellonella' ...

'') was able to adapt its defense mechanisms during 25 generations, while being under constant selective pressure from the fungus ''B. bassiana''. The moth developed resistance, but apparently, at a cost.

Containment leak

In March 2013, genetically modified ''Beauveria bassiana'' was found in a number of research laboratories and greenhouses outside of a designated containment area at Lincoln University in Christchurch, New Zealand. The Ministry for Primary Industries investigated the leak.

Discovery and name

Relation to ''Cordyceps'' and other fungi

White muscardine disease

Morphology of the fungus

Use in biological control of insects

Containment leak

See also

References

Further reading