Fernández-Salas Agustín, Alonso-Díaz Miguel Angel, Alonso-Morales Rogelio Alejandro
Centro de Enseñanza, Investigación y Extensión en Ganadería Tropical, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Km. 5.5 Carretera Federal Tlapacoyan-Martínez de La Torre, C.P. 93600, Martínez de La Torre, Veracruz, Mexico.
Centro de Enseñanza, Investigación y Extensión en Ganadería Tropical, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Km. 5.5 Carretera Federal Tlapacoyan-Martínez de La Torre, C.P. 93600, Martínez de La Torre, Veracruz, Mexico.
Exp Parasitol. 2019 Sep;204:107729. doi: 10.1016/j.exppara.2019.107729. Epub 2019 Jul 23.
The objectives of this study are to: (1) evaluate the in vitro acaricidal effect of 54 Metarhizium anisopliae strains, six Beauveria bassiana strains and one Purpureocilium lilacinum strain, against the larvae of two populations of Rhipicephalus microplus (multi-resistant and susceptible to chemical acaricides); and (2) determine the lethal concentrations required to eliminate the 50% (LC50) and 99% (LC99) of larvae through the use of entomopathogenic fungi (EF) with high acaricidal effects. The mortality percentage was evaluated by larval immersion tests at a dose of 1 × 10 conidia/mL for each fungal strain. For calculating LC50 and LC99, four doses (1 × 10, 1 × 10, 1 × 10 and 1 × 10) were used. Nine strains of M. anisopliae and the P. lilacinum strain showed a high mortality percentage in the R. microplus larvae of both populations. The best strains that showed the lowest values of LC50 and LC99 for tick elimination were MaV50 and PlV01. In conclusion, several strains of entomopathogenic fungi showed a high acaricidal effect against the R. microplus larvae of both populations, suggesting that these fungi might be a promissory adjuvant in the control of R. microplus, including those who are resistant. Finally, the discovery of a P. lilacinum strain with a high acaricidal effect is also reported.
（1）评估54株金龟子绿僵菌、6株球孢白僵菌和1株淡紫拟青霉对微小牛蜱两个种群（多抗性和对化学杀螨剂敏感）幼虫的体外杀螨效果；（2）通过使用具有高杀螨效果的昆虫病原真菌（EF），确定消除50%（LC50）和99%（LC99）幼虫所需的致死浓度。通过对每种真菌菌株以1×10分生孢子/毫升的剂量进行幼虫浸泡试验来评估死亡率百分比。为了计算LC50和LC99，使用了四个剂量（1×10、1×10、1×10和1×10）。九株金龟子绿僵菌和淡紫拟青霉菌株在两个种群的微小牛蜱幼虫中均表现出较高的死亡率百分比。对于蜱虫消除显示出最低LC50和LC99值的最佳菌株是MaV50和PlV01。总之，几种昆虫病原真菌菌株对两个种群的微小牛蜱幼虫均表现出高杀螨效果，这表明这些真菌可能是控制微小牛蜱（包括抗性蜱）的一种有前景的辅助手段。最后，还报道了发现一种具有高杀螨效果的淡紫拟青霉菌株。
