Isolation and identification of entomopathogenic fungi strains for Colorado potato beetle (Leptinotarsa decemlineata) control.

This article focuses on the isolation, identification, and evaluation of entomopathogenic fungi (EPF) strains from soil samples in the Czech Republic as potential biological control agents against the Colorado potato beetle (Leptinotarsa decemlineata), a major pest resistant to many chemical insecticides. Twenty EPF strains belonging to Beauveria bassiana, Beauveria brongniartii, Cordyceps fumosorosea, Purpureocillium lilacinum, Metarhizium brunneum, and Metarhizium robertsii were isolated and characterized using morphological and molecular markers (28S rRNA, ITS, and elongation factor 1-alpha gene sequences). Laboratory bioassays demonstrated significant variability in virulence among strains, with Metarhizium species, particularly M. robertsii strain MAN3b, showing the highest pathogenicity against adult beetles. The study suggests that certain indigenous EPF strains, especially from the genus Metarhizium, hold promise for developing environmentally safe mycoinsecticides for integrated pest management of the Colorado potato beetle.