Chapter 14: Fungi as Agents of Biological Control

Fungi possess several inherent advantages for pest management including high reproductive rates, short generation times, narrow host ranges, and the capacity to produce dormant spores that remain viable across extended periods. The discussion organizes around three primary domains of fungal biocontrol application. First, entomogenous fungi target arthropod pests through direct parasitism and infection, with species like Beauveria bassiana and Metarhizium anisopliae serving as commercial mycoinsecticides against agricultural threats including Colorado potato beetles, locusts, and mosquito larvae. Additional fungal agents such as Verticillium lecanii control hemipteran pests like aphids and whiteflies, while Hirsutella thompsonii addresses citrus mite infestations. Second, mycoherbicidal fungi attack plant pathogens causing weed species, with rust fungi demonstrating remarkable success against invasive vegetation in international contexts and commercial products such as Colletotrichum gloeosporioides targeting specific weed species with precision unavailable through broad-spectrum chemical herbicides. Third, mycoparasitic fungi suppress other pathogenic fungi through antagonistic mechanisms including direct parasitism, competitive exclusion, and induced cross-protection. Trichoderma species exemplify this category by attacking soil-borne pathogens like Rhizoctonia and Sclerotium across diverse agricultural and horticultural systems. The chapter emphasizes that although fungal biocontrol agents operate more gradually than chemical alternatives, their inherent safety profiles, ecological specificity, and self-perpetuating population dynamics establish them as essential components of integrated pest management frameworks. Historical perspectives tracing from silkworm disease observations to contemporary commercial applications illustrate the expanding role of mycological approaches in global agricultural sustainability and disease prevention strategies.