ABSTRACT
The fungi comprise a large, heterogeneous, and ubiquitous group of heterotrophic organisms living as saprophytes or parasites, or associated with other organisms as symbionts. The majority of known fungi, whether normally parasitic or not, are capable of living on dead organic material. In Europe, entomogenous fungi attacking honeybee, silkworm, and a few other insects were alluded to by poets and naturalists around the 18th century. High relative humidity and/or free water are generally required by entomogenous fungi for germination of infective propagules and formation of reproductive structures outside the host. Mass production, a basic requirement for the development of an entomogenous fungus as a microbial control agent, is dependent on man’s ability to isolate and culture candidate fungi in a living organism or on a nonliving substrate. Hirsutella thompsonii causes seasonal epizootics in citrus rust mite populations lasting two to three weeks during the summer when mite densities reach injurious levels in Florida.
