The association of extracts of Achyrocline satureioides and the fungus Beauveria bassiana against the tick Rhipicephalus microplus

Author(s)

Fantatto, Rafaela Regina ; Gainza, Yousmel Aleman ; Figueiredo, Amanda ; Sorrechia, Rodrigo ; de Souza Chagas, Ana Carolina ; Linhari Rodrigues Pietro, Rosemeire Cristina

• Document type: Journal article
• Source: Experimental and Applied Acarology; v. 87, n. 4, p. 13-pg., 2022-08-24.

Abstract

The tick Rhipicephalus microplus (Canestrini) is a major economic hurdle to the global livestock industry. The incorrect and indiscriminate control carried out by synthetic chemical compounds has contributed to the emergence of parasite resistance present today to many products available in the veterinary market. Effective, economically viable and potentially safe alternatives need to be investigated, including herbal medicine and biological control by entomopathogenic fungi. In this study, extracts from Achyrocline satureioides (Lam.) DC. obtained by extraction with solvents of different polarities associated and not associated with the entomopathogenic fungus Beauveria bassiana (Balsamo-Crivelli) Vuillemin were evaluated on different stages of the life cycle of R. microplus. The activity of plant extracts, fungus and their associations in ticks was analyzed in vitro through the adult immersion test, larval packet test and larval immersion test. The highest efficacy on engorged females (43.3%) was reached by the hexanic partition (ASh) at 5 mg/mL + fungus, reducing larval hatchability. ASh associated with B. bassiana also caused high mortality of larvae, reaching LC50 of 6.23 and 2.65 mg/mL in the packet and immersion tests, respectively. The results obtained showed that extracts, when used in combination with the fungus, have their action enhanced, reaching 100% mortality of larvae. Among the evaluated methodologies, it was observed that the larval immersion test allows better assessment, due to the time of contact with the larvae. The results obtained with A. satureioides associated with the fungus are considered promising and open new perspectives for future product development. (AU)

• FAPESP's process: 18/14116-4 - Acaricide evaluation of natural derivatives of Achyrocline satureioides and Schinus lentiscifolius in association with biotechnological products obtained from entomopathogenic fungi on the bovine tick Rhipicephalus (Boophilus) microplus
• Grantee: Rosemeire Cristina Linhari Rodrigues Pietro
• Support Opportunities: Regular Research Grants