Controlling Argas arboreus and A. persicus (Acari: Argasidae) by Adiantum capillus-veneris L. extracts with phytochemical analysis.

Argas species are parasites associated mostly with birds. Their infestations of the host may cause blood loss, resulting in anemia and finally death. Egypt loses millions of tons annually from birds because of these parasites. In addition, they can transmit pathogens to animals and humans. The acaricidal effects of the ethanolic and methanolic extracts of Adiantum capillus-veneris at different concentrations (1-4%) against semi-fed adults of Argas arboreus and A. persicus were investigated during 30 days after treatments. Mobility and mortality, acaricide efficacy, and the concentration that kills 50% of specimens (LC50) were estimated. The percentage of dead adults of both Argas species appeared during 6 days considerably until 30 days was significantly increased after treatment of either ethanol or methanol extracts of Adiantum at 1-4%, versus control groups. Ethanolic extracts (100% mortality) were more effective than methanolic ones (90% mortality) for both Argas species. Argas arboreus (80% efficacy and 5.9% LC50) was more resistant than A. persicus (100% efficacy and 4.1% LC50). Generally, males were more resistant than females. The chemical profile (by gas chromatography-mass spectrometry analysis) for the ethanolic extract of Ad. capillus-veneris at 4% (the most effective extract) was provided for the first time, which showed that the major group was sugars and sugar alcohols, and the main components were thymol-ß-d-glucopyranoside, D-(-)-Tagatofuranose, D-Arabinose, D-Galactose, D-(-)-Fructofuranose and Anthracene, 1-methyl. The efficiency of all these components was discussed. Based on the findings, bioactive compounds present in Ad. capillus-veneris have the potential to be applied as substitutes for synthetic acaricides and a biological control agent in the management of A. arboreus and A. persicus ticks.

Chemical identification of Tagetes minuta Linnaeus (Asteraceae) essential oil and its acaricidal effect on ticks / Caracterização química e efeito acaricida do óleo essencial de Tagetes minuta Linnaeus (Asteraceae) em carrapatos

The control of tick species that affect animal production is vital for the economic welfare of the cattle industry. This study focused on testing the acaricidal activity of the essential oil from the leaves and stems of Tagetes minuta against several Brazilian tick species, including Rhipicephalus (Boophilus) microplus, Rhipicephalus sanguineus, Amblyomma cajennense and Argas miniatus. The chemical composition of the essential oil was determined by chromatography and spectroscopy analyses, which revealed the presence of monoterpenes. The adult immersion test (AIT) and the larval packet test (LPT) were used to evaluate the efficacy of T. minuta essential oil in tick management at concentrations of 2.5, 5, 10, 20 and 40%. The results demonstrated that the T. minuta essential oil had over 95% efficacy against four species of ticks at a concentration of 20%. These results suggest that the essential oil of T. minuta could be used as an environmentally friendly acaricide.(AU)

O controle de carrapatos que causa impacto na produção de bovinos possui importância econômica para a cadeia produtiva. Neste trabalho objetivou-se testar a atividade acaricida do óleo essencial das folhas e caules de Tagetes minuta contra várias espécies de carrapatos brasileiros, incluindo Rhipicephalus (Boophilus) microplus, Rhipicephalus sanguineus, Amblyomma cajennense e Argas miniatus. A composição química do óleo foi determinada por GC-MS e análises de espectroscopia de RMN, que revelaram a presença de monoterpenos. Na avaliação destas substâncias no controle do carrapato foram empregados os testes de imersão de adulto (TIA) e o de pacote de larvas (TPL) para o extrato de óleo de T. minuta nas concentrações de 2,5%; 5%; 10%; 20% e 40%. Os resultados do TPL e TIA demonstraram que o óleo essencial na concentração de 20% de T. minuta apresenta eficácia superior a 95% nas quatro espécies de carrapato. Estes resultados sugerem que o óleo essencial de T. minuta pode ser usado como um acaricida eficaz e com baixo impacto ambiental.(AU)

Acaricidal efficacy of Myrrh (Commiphora molmol) on the fowl tick Argas persicus (Acari: Argasidae).

Five concentrations of purified extract of Myrrh from Commiphora molmol tree were prepared to study its effects on the fowl tick Argas persicus under laboratory conditions. The results revealed that Myrrh had dependant dose toxic effect on the adult female of A. persicus. Toxicity increased gradually daily post treatment. The LC50 was 1.28%, 0.88%, 0.84%, 0.50% and 0.42% at Ist, 2nd, 3rd, 6th and 12th days respectively. At 12th day, the recorded mortality rates were 63, 67, 76, 87 and 94% for concentrations, 0.625, 1.25, 2.5, 5 and 10%, respectively against 5% in control. Histopathological and Transmission election microscope (TEM) examinations showed the lysing of epithelial gut cells in treated groups. The lysed epithelial gut cells showed irregularly distributed nucleus, commonly at low concentrations and rarely in high concentrations of Myrrh. The lysed epithelial gut cells, without nucleus or with aggregated one beside the basal lamina, were common at high concentrations and rare in low concentrations of Myrrh. Consequently, Myrrh can rapidly penetrate the cuticle to body cavity, destroy the epithelial gut cells and finally cause the death of ticks.