USDA-ARS, Knipling-Bushland US Livestock Insects Research Laboratory, Kerrville, TX.
Entomology and Nematology Department, University of Florida, Gainesville, FL.
J Med Entomol. 2019 Jun 27;56(4):1145-1149. doi: 10.1093/jme/tjz012.
Anecdotal evidence of pyrethroid insecticide product failure for the control of stable fly [Stomoxys calcitrans (L.)] populations in the United States and worldwide prompted us to evaluate the frequency of knockdown resistance (kdr)-type polymorphisms within the voltage-sensitive sodium channel (Vssc) gene of field collected specimens from the United States, France, Costa Rica, and Thailand. The kdr-his allele (L1014H), associated with permethrin resistance, was detected in stable flies from the 10 states sampled in the United States, as well as from Costa Rica and France (Toulouse). Field collections of stable flies from California (Modesto) and New York (Cliffton Springs) exhibited reduced susceptibility upon exposure to a diagnostic permethrin concentration of 10× LC99, but survival did not appear to strictly associate with frequency of the kdr-his allele. This suggests that there are additional resistance mechanisms contributing to the phenotype in these states. The kdr allele (L1014F) was detected for the first time in stable flies originating in France and Thailand, and an improved, DNA-based diagnostic assay was developed and validated for use in future screens for kdr and kdr-his allele frequencies from field collections. The absence of kdr in United States and Costa Rica populations suggests that the allele is currently restricted to Europe and Asia.
在美国和世界各地，有关拟除虫菊酯杀虫剂产品控制厩螫蝇（Stomoxys calcitrans (L.)）种群失败的传闻证据，促使我们评估了美国、法国、哥斯达黎加和泰国田间采集样本中电压门控钠离子通道（Vssc）基因中击倒抗性（kdr）型多态性的频率。与氯菊酯抗性相关的 kdr-his 等位基因（L1014H）在美国 10 个州、哥斯达黎加和法国（图卢兹）的厩螫蝇中被检测到。加利福尼亚州（莫德斯托）和纽约州（克利夫顿斯普林斯）的厩螫蝇田间采集样本在接触诊断浓度为 10×LC99 的氯菊酯时表现出较低的敏感性，但存活似乎与 kdr-his 等位基因的频率没有严格关联。这表明在这些州，还有其他的抗性机制导致了这种表型。kdr 等位基因（L1014F）首次在来自法国和泰国的厩螫蝇中被检测到，并且开发并验证了一种改进的基于 DNA 的诊断检测方法，以便在未来从田间采集样本中筛选 kdr 和 kdr-his 等位基因频率时使用。美国和哥斯达黎加种群中没有 kdr 表明该等位基因目前仅限于欧洲和亚洲。
