In vitro pathogenicity of Metarhizium anisopliae s.l. on larvae and nymphs of Ornithodoros mimon (Acari: Argasidae)
ABSTRACT. Perinotto W.M.S., Landulfo G.A., Camargo M.G., Golo P.S., Angelo I.C., Quinelato S., Barros-Batesti D.M., Bittencourt V.R.E.P. [In vitro pathogenicity of Metarhizium anisopliae s.l. on larvae and nymphs of Ornithodoros mimon (Acari: Argasidae).] Patogenicidade in vitro de Metarhizium anisopliae s.l. sobre larvas e ninfas de Ornithodoros mimon (Acari: Argasidae). Revista Brasileira de Medicina Veterinária, 35(Supl.2):43-47, 2013. Departamento de Parasitologia Animal, IV, Anexo 1, Universidade Federal Rural do Estado do Rio de Janeiro, BR 465 Km 7, Seropédica, RJ 23897-970, Brasil. E-mail: email@example.com Ornithodoros mimon is an argasid tick common on Chiroptera in the Neotropical region, which also bites humans aggressively and it is often found in human habitations. Currently, there are no control methods for argasid ticks. However, previous works already reported the susceptibility of species of Argasidae to entomopathogenic fungi. Thus, the present study aimed to determine the in vitro pathogenecity of Metarhizium anisoplie s.l. on larvae and nymphs first instar of O. mimon. The biological parameter evaluated was the percentage of mortality of the larvae and nymphs. The results showed 80% larval mortality in the concentration of 107 conidia/mL and 91.4% for larvae subjected to a concentration of 108 conidia/mL. The engorged nymphs immersed in suspensions 107 conidia/ml were more susceptible to fungus that unfed nymphs. In the suspensions 108 conidia/ mL no difference was observed, because the average percentage mortality was above 95% for engorged and unfed nymphs. Based on the results obtained, we concluded that immature stages of O. mimon are susceptible to M. anisoplie s.l.