Population Biology, Ecology, and Evolution Graduate Program Emory University Atlanta, GA, USA.
Department of Environmental Sciences, Emory University Atlanta, GA, USA.
J Med Entomol. 2024 Sep 10;61(5):1155-1167. doi: 10.1093/jme/tjae088.
Wolbachia pipientis (Hertig, 1936), also referred as Wolbachia, is a bacterium present across insect taxa, certain strains of which have been demonstrated to impact the fitness and capacity to transmit viruses in mosquitoes, particularly Aedes aegypti (Linnaeus, 1762). Most studies examine these impacts in limited sets of environmental regimes. Here we seek to understand the impacts of environmentally relevant conditions such as larval density, temperature, and their interaction on wAlbB-infected A. aegypti. Using a factorial design, we measured wAlbB stability (relative density, post-emergence in females, and in progeny), the ability for wAlbB to induce cytoplasmic incompatibility, and bacterial effects on mosquito fitness (fecundity, fertility, and body mass) and performance (adult survival and time to pupation) across 2 temperature regimes (fluctuating and constant) and 2 initial larval densities (low and high). Fluctuating daily regimes of temperature (27 to 40 °C) led to decreased post-emergence wAlbB density and increased wAlbB density in eggs compared to constant temperature (27 °C). An increased fecundity was found in wAlbB-carrying females reared at fluctuating temperatures compared to uninfected wild-type females. wAlbB-carrying adult females showed significantly increased survival than wild-type females. Contrarily, wAlbB-carrying adult males exhibited a significantly lower survival than wild-type males. We found differential effects of assessed treatments (Wolbachia infection status, temperature, and larval density) across mosquito sexes and life stages. Taken together, our results indicate that realistic conditions may not impact dramatically the stability of wAlbB infection in A. aegypti. Nonetheless, understanding the ecological consequence of A. aegypti-wAlbB interaction is complex due to life history tradeoffs under conditions faced by natural populations.
沃尔巴克氏体（Hertig，1936），也称为沃尔巴克氏体，是一种存在于昆虫类群中的细菌，某些菌株已被证明会影响蚊子的适应性和传播病毒的能力，特别是埃及伊蚊（Linnaeus，1762）。大多数研究都在有限的环境制度中检查这些影响。在这里，我们试图了解环境相关条件（如幼虫密度、温度及其相互作用）对感染 wAlbB 的埃及伊蚊的影响。使用析因设计，我们测量了 wAlbB 的稳定性（相对密度、雌性后代中的密度以及后代中的密度）、wAlbB 诱导细胞质不亲和的能力以及细菌对蚊子适应性（繁殖力、生育力和体重）和性能（成虫存活率和化蛹时间）的影响，跨越 2 个温度范围（波动和恒定）和 2 个初始幼虫密度（低和高）。波动的日温度（27 至 40°C）导致与恒温（27°C）相比，出现在埃及伊蚊中的 wAlbB 密度降低，而卵中的 wAlbB 密度增加。与未感染的野生型雌性相比，在波动温度下饲养的携带 wAlbB 的雌性的繁殖力增加。携带 wAlbB 的成年雌性的存活率明显高于野生型雌性。相反，携带 wAlbB 的成年雄性的存活率明显低于野生型雄性。我们发现评估处理（沃尔巴克氏体感染状况、温度和幼虫密度）在蚊子性别和生命阶段的影响存在差异。总之，我们的结果表明，现实条件可能不会对埃及伊蚊中 wAlbB 感染的稳定性产生巨大影响。尽管如此，由于自然种群面临的生活史权衡，理解埃及伊蚊-沃尔巴克氏体相互作用的生态后果是复杂的。
