Bio-Pesticide Control of the Brown Dog Tick (Rhipicephalus sanguineus) in Egypt by using Two Entomopathogenic Fungi (Beauveria bassiana and Metarhizium anisopliae)

Abstract

The current study examined the potential use of entomopathogenic fungi to control infestation of Rhipicephalus sanguineus. Examination of 514 dogs admitted to veterinary clinics in Egypt revealed that 67.5% were infested with R. sanguineus. Two hundred and sixty adult ticks were collected. Beauveria bassiana and Metarhizium anisopliae were then tested for their effect on these ticks. The in vitro effect of different concentrations of B. bassiana on engorged females, unfed females, fed males, eggs, larvae, and nymphs was strong for all three concentrations of B. bassiana compared with controls (P<0.05) and white fungal colonies grew on the surface of the ticks. The B1 of B. bassiana (108 conidia/ ml) was the most pathogenic on adult and developmental stages of ticks. The impact of different concentrations of M. anisopliae on adult and developmental stages in comparison with controls was similar, with the growth of green hyphae around eggs and adult ticks which prevented hatching and resulted in tick death. The M2 suspension (107 conidia/ml) had the most potent effect on adult ticks and developmental stages. The efficacy of this suspension was higher than that of the B1 concentration of B. bassiana (98 and 100% respectively). Therefore, 107conidia/ml of M. anisopliae seems to be the most effective fungus to use as bio-pesticide to control different developmental stages of R. sanguineus and may be a reasonable alternative to chemical treatment.