Metarhizium flavoviride | |
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Unidentified leafhopper (Cicadellidae) infected with M. flavoviride: Atewa forest, Ghana (2008) | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Fungi |
Division: | Ascomycota |
Class: | Sordariomycetes |
Order: | Hypocreales |
Family: | Clavicipitaceae |
Genus: | Metarhizium |
Species: | M. flavoviride |
Binomial name | |
Metarhizium flavoviride Gams & Roszypal, 1973 | |
Metarhizium flavoviride is a Sordariomycete in the order Hypocreales and family Clavicipitaceae. [1] The genus Metarhizium currently consists of 45 described species and are a group of fungal isolates that are known to be virulent against Hemiptera and some Coleoptera. M. flavoviride is described as its own species, but there also exists a variety of M. flavoviride, which is M. flavoviride var. flavoviride. [2] [3] Previously described varieties of M. flavoviride have been documented, however recent random amplified polymorphic DNA (RAPD) markers have assigned these varieties as new species. [2] The reassigned species are as follows: M. flavoviride Type E is now M. brasiliense; M. flavoviride var. minus is now M. minus; M. flavoviride var. novozealandicum is now M. novozealandicum; and M. flavoviride var. pemphigi is now M. pemphigi. [2] [3]
All species in the Metarhizium genus are entomopathogenic, infecting a variety of hosts ranging from those in the orders Coleoptera, Hemiptera, Diptera, and Orthoptera. Hosts are often agriculturally important pests. [2] [4] [5] [6] Historically, species in the Metarhizium genus have been distinguished from each other by morphological traits such as differences in conidial shape, color, and conidiogenous cells. These taxonomic morphological differences are mostly substantiated by allozyme analyses. [7] [8] [9] However, recent studies indicate that using morphological characteristics is not an accurate method to distinguish between different Metarhizium species and their respective varieties, and instead, molecular and genetic techniques should be used. [2] [3] [9]
M. flavoviride is mainly studied for its use as a biological control to reduce pesticide resistance in plants where hosts feed on, as well as to reduce the environmental impact of using pesticides on agricultural crops. [10] [11]
As with other Metarhizium species, there has been interest in developing isolates into mycoinsecticides: with work carried out on rice insect pests during the 1970–80s. [12] However, such isolates appear to be more difficult to mass-produce, so there has been less commercial activity than with other Metarhizium species. In light of new molecular techniques, we now know that references to this species for control of locusts (e.g. in early LUBILOSA Programme literature) should apply to Metarhizium acridum .
M. flavoviride conidia (spores) range in color from vibrant green to light grey-green. [1] [4] [13] Conidiogenous cells are 7–11 μm long and clavate, broadly ellipsoid, or ovoid. Conidia are relatively slow to develop. [4] [1]
Metarhizium species and M. flavoviride have been isolated from multiple soil types from all types of climates across all continents (excluding Antarctica) and have been found to infect many different arthropods. [2] M. flavoviride has been found in a wide range of soils, particularly in agricultural habitats; they are often found in soils associated with roots of plants where host pests feed on. [2] [5] [14] Some data have supported the finding that undisturbed habitats with naturally occurring vegetation are more likely to support entomopathogenic fungi such as M. flavoviride. [15] It is of interest to continue research regarding the abundance and occurrence of M. flavoviride as it concerns using entomopathogenic fungi as a form of biological control. [2]
In the Shaanxi province in China, it was found that the richness of Metarhizium species decreased with increasing elevation. [13]
M. flavoviride is facultatively saprophytic. M. flavoviride can be free-living in soil or in the rhizosphere of plants in the absence of a host. [2]
M. flavoviride infects mainly by penetrating the host through the cuticle and colonizes through the body cavity. The fungal propagule germinates, creates an appressorium, and generates a penetration peg which produces degradative enzymes that break down the cuticle. The fungal hyphae use the epicuticular waxes and lipids for growth. M. flavoviride secretes toxic secondary metabolites that facilitate infection of the hemolymph. Death of the host is caused by physical damage and loss of normal function. [5] [11]
Beauveria bassiana is a fungus that grows naturally in soils throughout the world and acts as a parasite on various arthropod species, causing white muscardine disease; it thus belongs to the group of entomopathogenic fungi. It is used as a biological insecticide to control a number of pests, including termites, thrips, whiteflies, aphids and various beetles. Its use in the control of bedbugs and malaria-transmitting mosquitos is under investigation.
An entomopathogenic fungus is a fungus that can kill or seriously disable insects.
Metarhizium robertsii – formerly known as M. anisopliae, and even earlier as Entomophthora anisopliae (basionym) – is a fungus that grows naturally in soils throughout the world and causes disease in various insects by acting as a parasitoid. Ilya I. Mechnikov named it after the insect species from which it was originally isolated – the beetle Anisoplia austriaca. It is a mitosporic fungus with asexual reproduction, which was formerly classified in the form class Hyphomycetes of the phylum Deuteromycota.
Delia flies are members of the Anthomyiidae family within the superfamily Muscoidae. The identification of different species of Delia can be very difficult for non-specialists as the diagnostic characteristics used for immature and/or female specimens may be inconsistent between species. Past taxonomic keys were not as comprehensive in their identification of Delia specimens; they were either too reliant on genetic characteristics, focused solely on a specific life stage, or were focused only on certain species. However current taxonomic keys aim to be more thorough by not only including morphological diagnostics for males, females, and immature specimens of various species, but also their genetic make-up or molecular barcode.
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.
Clonostachys rosea f. rosea, also known as Gliocladium roseum, is a species of fungus in the family Bionectriaceae. It colonizes living plants as an endophyte, digests material in soil as a saprophyte and is also known as a parasite of other fungi and of nematodes. It produces a wide range of volatile organic compounds which are toxic to organisms including other fungi, bacteria, and insects, and is of interest as a biological pest control agent.
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.
Raymond J. St. Leger is an American mycologist, entomologist, molecular biologist and biotechnologist who currently holds the rank of Distinguished University Professor in the Department of Entomology at the University of Maryland, College Park.
Metarhizium is a genus of entomopathogenic fungi in the Clavicipitaceae family. With the advent of genetic profiling, placing these fungi in proper taxa has now become possible. Most turn out to be the asexual forms (anamorphs) of fungi in the phylum Ascomycota, including Metacordyceps spp.
LUBILOSA was the name of a research programme that aimed at developing a biological alternative to the chemical control of locusts. This name is an acronym of the French title of the programme: Lutte Biologique contre les Locustes et les Sauteriaux. During its 13-year life, the programme identified an isolate of an entomopathogenic fungus belonging to the genus Metarhizium and virulent to locusts, and went through all the necessary steps to develop the commercial biopesticide product Green Muscle based on its spores.
Metarhizium acridum is the new name given to a group of fungal isolates that are known to be virulent and specific to the Acrididea (grasshoppers). Previously, this species has had variety status in Metarhizium anisopliae ; before that, reference had been made to M. flavoviride or Metarhizium sp. describing an "apparently homologous and distinctive group" of isolates that were most virulent against Schistocerca gregaria in early screening bioassays.
Metarhizium majus is the name given to a group of fungal isolates that are known to be virulent against Scarabaeidae, a family of beetles. Previously, this species has had variety status in Metarhizium anisopliae and its name is derived from characteristically very large spores for the genus Metarhizium. There has been considerable interest in developing isolates of this species into mycoinsecticides: especially against the coconut and oil palm beetle pest Oryctes in SE Asia, the Pacific region and Africa.
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.
Muscardine is a disease of insects. It is caused by many species of entomopathogenic fungus. Many muscardines are known for affecting silkworms. Muscardine may also be called calcino.
Zoophthora is a genus of fungi in the family Entomophthoraceae. Like other taxa in this family, Zoophthora species cause disease in insects and as such are considered entomopathogenic fungi.
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Hoplocampa testudinea, the apple sawfly or European apple sawfly, is a species of sawfly in the family Tenthredinidae. It is native to Europe but has been accidentally introduced into North America where it became invasive. The larvae feed inside the developing fruits of the apple tree.
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Tariq Butt is an entomologist in the UK, he is Professor of Biosciences at Swansea University in Wales.
Donald W. Roberts was an American insect pathologist and one of the originators of that field. He was especially known for research into biological pest control of Lepidoptera by Metarhizium but also Beauveria bassiana. He was a Research Professor Emeritus in the Biology Department of Utah State University.