A??o de Beauveria bassiana e Metarhizium anisopliae sobre popula??es de Rhipicephalus (Boophilus) microplus de diferentes localidades

• Autor(a) principal: Perinotto, Wendell Marcelo de Souza
• Data de Publicação: 2010
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRRJ
• Texto Completo: https://tede.ufrrj.br/jspui/handle/tede/794
• topic: Rhipicephalus (B.) microplus; Beauveria bassiana; Metarhizium anisopliae; susceptibilidade e controle biol?gico; susceptibility and biological control; Medicina Veterin?ria

Recent studies have indicated the possibility of difference in susceptibility between different populations of ticks, while undergoing treatment with entomopathogenic fungi. To assess whether this difference actually occurs, this study intents to verify the in vitro effect of fungi Metarhizium anisopliae and Beauveria bassiana on two distinct populations of Rhipicephalus (B.) microplus collected from different properties. Experiments were conducted on engorged females, eggs and larvae. To evaluate the effect of fungi female reproductive parameters were observed. In eggs, the hatch percentage was evaluated, and in larvae, the mortality rate was analyzed. Five groups were formed (108, 107 con?dia/ml of M. anisopliae; 108, 107 con?dia/ml of B. bassiana and control group) with 10 repetitions each. The specimens were immersed in one ml of the suspension for three minutes and the control group was exposed only to diluent. The results showed that the fungi were efficient, influencing all females s reproductive parameters of both properties. To verify the susceptibility of different populations statistical analysis were carried out comparing the treatments on females of different origins. The following parameters presented significant difference: periods of the pre oviposition, larvae hatch and egg production index. Furthermore, B. bassiana was more effective than M. anisopliae on engorged female. In the bioassay with eggs the hatch percentage ranged between 3.1 and 49.5% in one property and from 3.4 to 42.7% in another, but there was no significant difference between the two populations at this stage of R. (B.) microplus. At the bioassay with larvae the mortality percentage of larvae ranged from 91.8 to 98.7% in one and 71.0 to 94,0% in another property. Moreover, the average lethal time (LT 90) ranged from 19.52 to 27.51 days in one of the properties and 22.89 to 37.31 days in the other. Through these results, it can be concluded the entomopathogenic fungi used in this study are effective in controlling this tick species. However, different populations have variation in their susceptibility to B. bassiana and M.anisopliae.