Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Japan.
Graduate School of Science and Engineering, Ehime University, Matsuyama, Japan.
PLoS Negl Trop Dis. 2021 Feb 26;15(2):e0009139. doi: 10.1371/journal.pntd.0009139. eCollection 2021 Feb.
Dengue is endemic in tropical and subtropical countries and is transmitted mainly by Aedes aegypti. Mosquito movement can be affected by human-made structures such as roads that can act as a barrier. Roads can influence the population genetic structure of Ae. aegypti. We investigated the genetic structure and gene flow of Ae. aegypti as influenced by a primary road, España Boulevard (EB) with 2000-meter-long stretch and 24-meters-wide in a very fine spatial scale. We hypothesized that Ae. aegypti populations separated by EB will be different due to the limited gene flow as caused by the barrier effect of the road. A total of 359 adults and 17 larvae Ae. aegypti were collected from June to September 2017 in 13 sites across EB. North (N1-N8) and South (S1-S5) comprised of 211 and 165 individuals, respectively. All mosquitoes were genotyped at 11 microsatellite loci. AMOVA FST indicated significant genetic differentiation across the road. The constructed UPGMA dendrogram found 3 genetic groups revealing the clear separation between North and South sites across the road. On the other hand, Bayesian cluster analysis showed four genetic clusters (K = 4) wherein each individual samples have no distinct genetic cluster thus genetic admixture. Our results suggest that human-made landscape features such as primary roads are potential barriers to mosquito movement thereby limiting its gene flow across the road. This information is valuable in designing an effective mosquito control program in a very fine spatial scale.
登革热流行于热带和亚热带国家，主要由埃及伊蚊传播。人为结构如道路会影响蚊子的移动，因为道路可以作为一种屏障。道路会影响埃及伊蚊的种群遗传结构。我们调查了主要道路西班牙大道（EB）对埃及伊蚊的遗传结构和基因流动的影响，EB 道路全长 2000 米，宽 24 米，这是一个非常精细的空间尺度。我们假设由于道路的屏障效应导致基因流动有限，因此被 EB 隔开的埃及伊蚊种群将有所不同。2017 年 6 月至 9 月，我们在 EB 沿线的 13 个地点共收集了 359 只成蚊和 17 只幼虫。北（N1-N8）和南（S1-S5）分别包括 211 人和 165 人。所有蚊子均在 11 个微卫星基因座上进行了基因分型。AMOVA FST 表明道路两侧的遗传分化显著。构建的 UPGMA 树状图发现了 3 个遗传群，显示了道路两侧北和南地区的明显分离。另一方面，贝叶斯聚类分析显示有 4 个遗传群（K=4），其中每个个体样本没有明显的遗传群，因此存在遗传混合。我们的研究结果表明，人为景观特征（如主要道路）可能是蚊子移动的障碍，从而限制了其在道路上的基因流动。这一信息对于在非常精细的空间尺度上设计有效的蚊虫控制计划非常有价值。
