Entomopathogenic fungus


An entomopathogenic fungus is a fungus that can act as a parasite of insects and kills or seriously disables them.
s killed by the entomopathogenic fungus Beauveria bassiana

Typical life cycle

These fungi usually attach to the external body surface of insects in the form of microscopic spores. Under the right conditions of temperature and humidity, these spores germinate, grow as hyphae and colonize the insect's cuticle; which they bore through by way of enzymatic hydrolysis, reaching the insects' body cavity. Then, the fungal cells proliferate in the host body cavity, usually as walled hyphae or in the form of wall-less protoplasts. After some time the insect is usually killed, and new propagules are formed in or on the insect if environmental conditions are again right. High humidity is usually required for sporulation.

Groups

The entomopathogenic fungi include taxa from several of the main fungal groups and do not form a monophyletic group. Many common and/or important entomopathogenic fungi are in the order Hypocreales of the Ascomycota: the asexual phases Beauveria, Isaria, Hirsutella, Metarhizium, Nomuraea and the sexual state Cordyceps; others belong in the order Entomophthorales of the Zygomycota.
Related fungi attack and kill other invertebrates.

Pest control

Since they are considered natural mortality agents and environmentally safe, there is worldwide interest in the use and manipulation of entomopathogenic fungi for biological control of insects and other arthropod pests. In particular, the asexual phases of Ascomycota are under intense scrutiny due to traits favouring their use as biological insecticides.

Production

Most entomopathogenic fungi can be grown on artificial media. However, some require extremely complex media; others, like Beauveria bassiana and exploitable species in the genus Metarhizium, can be grown on starch-rich substrates like cereal grains.

[Virulence]

The Entomophthorales are often reported as causing high levels of mortality in nature. These fungi are highly virulent. The anamorphic Ascomycota are reported as causing epizootics less frequently in nature.
Also important for pesticide development are their properties regarding specificity, storage, formulation, and application.