ABSTRACT
Commonly referred to as microsporidians, entomopathogenic protozoans are an extremely diverse group of attacking invertebrates including insect species of many kinds as well as rangeland locusts and grasshoppers. They are generally host-specific and slow-acting, producing chronic infections with general debilitation of the host. The spore formed by the protozoan is the infectious stage and has to be ingested by the insect host for pathogenicity. The spore germinates in the midgut and sporoplasm is released invading the target cells causing infection of the host. The infection results in reduced feeding, vigor, fecundity and longevity of the insect host as inundatively applied microbial control agents. Only some species have been found successful, for instance, the utility of Nosema locustae as a grasshopper biocontrol agent remains reasonable, whereas Vairimorphanecatrix is with great commercial potential against caterpillar pests. The Nosemapyrausta is another beneficial microsporidian that reduces fecundity and longevity of the adults and also causes mortality of the larvae of the European corn borer. Some microsporidia are being further investigated as microbial insecticides, but the technology is new, and more work is needed to perfect the use of these o4rganisms.
