Entomopathogenic fungal metabolites and their biotechnological applications for sucking insect pests

Fungal secondary metabolites and virulence factors are central to the ecological success of entomopathogenic fungi (EPF) and represent untapped resources for sustainable pest management, especially against sucking insect pests. EPF initiates infection by penetrating the insect cuticle, then deploys a repertoire of toxic metabolites into the hemocoel to suppress host defenses and accelerate mortality. Key examples, such as beauvericin from Beauveria bassiana and destruxin from Metarhizium anisopliae, exemplify how these compounds function as both potent virulence factors and promising biocontrol agents. Structurally diverse metabolites-including nonribosomal peptides, alkaloids, terpenes, and polyketides-are synthesized via tightly regulated biosynthetic pathways that optimize pathogenicity. For decades, the genetic and biochemical mechanisms governing these processes remained largely unexplored. However, breakthroughs in next-generation sequencing and targeted genetic engineering have unveiled critical genes and regulatory networks underlying metabolite production and host-fungus interactions. This knowledge is enabling the rational enhancement of EPF strains and the strategic deployment of their metabolites in pest control programs. Harnessing fungal metabolites with optimized virulence offers a targeted, environmentally safe alternative to conventional insecticides, with reduced risks to nontarget organisms and minimized chemical residues. Continued research into the molecular ecology, biosynthetic innovation, and field performance of these compounds will be pivotal in translating laboratory discoveries into robust, field-ready biocontrol solutions for managing economically important insect pests.