Virulence of Metarhizium anisopliae and Beauveria bassiana to Ctenocephalides felis felis

Ctenocephalides felis felis is a flea species that parasitizes dogs and cats. The current study verified the in vitro virulence of the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana to eggs and adults of C. felis felis. The fungal isolates were cultivated on rice grains in plastic bags. Conidial suspensions were then prepared by immersing the grains in Tween 80 aqueous solution (0.01%). Eggs and adults of C. felis felis were obtained from a laboratory colony. Experiments were composed of one control and four treatment groups (10(5), 10(6), 10(7), and 10(8) conidia mL(-1)). Both insect pathogens inhibited egg hatchability and caused adult mortality. Among isolates used in this study, M. anisopliae (isolate E9) was the most successful at inhibiting hatching, while B. bassiana (isolate 986) was the most powerful for causing mortality in adults. The results indicate that these entomopathogenic fungi have promising potential for use in controlling both C. felis felis egg and adult stages.