[In vitro pathogenicity of fungic formulation on nymphs and adults of Rhipicephalus sanguineus (Latreile, 1806) (Acari:Ixodidae)].

Rhipicephalus sanguineus is responsible for transmitting several pathogenic agents, such as: Babesia sp. and Ehrlichia sp.. This species is known as the brown dog tick and has wide geographical distribution. The purpose of this work was to evaluate the pathogenicity of biological formulations of Beauveria bassiana and Metarhizium anisopliae applied to the fed nymphs and adults of R. sanguineus under laboratory conditions. The following treatments were evaluated: control, distilled water with tween 80, emulsible concentrated, cellulose polymerized gel, fungus mixed with emulsible concentrated, fungus mixed with cellulose polymerized gel and fungus mixed with emulsible concentrated and cellulose polymerized gel. Each treatment was repeated ten times. The survival of fed nymphs and unfed adults was evaluated on the 5th, 10th, 15th and the 20th days after treatments. Significant differences were observed between the treatments (p<0.05). The treatment with M. anisopliae mixed with emulsible concentrated and cellulose polymerized gel showed the lower survival on the 15th and 20th days after treatment. We can conclude that the fungi formulation is harmful to fed nymphs and unfed adults of R. sanguineus in vitro, on this account it is suggested its use for the microbial control of this tick.