Potencial de granulado de Metarhizium spp. para controle da fase não parasitária do carrapato Rhipicephalus microplus

• Autor(a) principal: Prieb, Andreisa
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000001g74
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/6192
• topic: Carrapato; Fungos entomopatogênicos; Controle microbiano; Ticks; Entomopathogenic fungi; Microbial control; MEDICINA::ANATOMIA PATOLOGICA E PATOLOGIA CLINICA

Rhipicephalus microplus is one of the main parasites found in Brazilian cattle herds; it is vector of pathogens causing severe economic losses. Currently, the control of R. microplus is conducted almost exclusively by the use of chemical products applied to parasitized hosts; however, the continued use of these products may lead ticks to resistance, and human health to damage. New methods for tick control that causes low damage to humans and to the environment are required; therefore, the use of entomopathogenic fungi has been investigated for biological control purposes, and the fungus Metarhizium has shown efficacy against R. microplus. The current study investigated the the efficacy of M. anisopliae and M. robertsii to control the non-parasitic phase of R. microplus. Bioassays were conducted in Petri dishes containing 5 g of sterile soil and 0.003 g of granules of formulated fungi spread evenly over the soil surface. One engorged female was placed in each plate for evaluation of their biology. The mean number of hatched larvae obtained from groups of females treated with granules of the isolate CG 632 was 604, while 385 larvae were obtained from the groups treated with granules of CG 168, and 87 from groups treated with CG 47; in the control groups, 2,896 larvae hatched. The mean oviposition period of females treated with granules of CG 168 or CG 632 was, respectively, 2.8 and 0.9 days, while in the control groups the mean oviposition period was 14.2 days. The statistical analysis revealed that both the oviposition period of engorged females and the number of hatched larvae showed significance at 1% of probability (P<0.01). The current study revelaed that the fungal isolates tested, M. anisopliae and M. robertsii, formulated in granules were able to reduce progeny of R. microplus under controlled conditions, suggesting their potential to control the non-parasitic phase of the R. microplus tick.