Metarhizium


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 of fungi in the phylum Ascomycota, including Metacordyceps spp.

Species

Before molecular techniques were introduced at the end of the 20th century, Metarhizium species were identified on morphological characteristics. The 'original' species included: M. anisopliae, M. brunneum, M. cicadinum, M. cylindrosporum, M. flavoviride, M. taii, M. truncatum, and M. viridicolumnare.
In 2009, nine former varieties of the type species M. anisopliae were assigned species status. New species have continued to be identified, with original names sometimes re-instated ; the index fungorum currently lists:
The teleomorphs of Metarhizium species appear to be members of the genus Metacordyceps. Metacordyceps taii has been described as the teleomorph of Metarhizium taii:
a name that has now been restored.
Whether the other varieties of M. anisopliae have their own teleomorphs is not yet clear. Some, if not most, strains of M. anisopliae possibly have lost the capability of reproducing sexually.

Locust control

In the 1990s, the LUBILOSA research programme proved that M. acridum in its spore form was effective in killing locusts and other members of the Acrididea families with no deleterious effects found in field trials on any nontarget species except for the domesticated silk worm Bombyx mori. It is currently produced as a biopesticide under the name Green Guard by Becker Underwood of Australia for the control of locusts and wingless grasshoppers; a similar product called Green Muscle produced by LUBILOSA is designed for the control of short-horned grasshoppers.