Microbial Mediation of Habitat Selection and Production

描述：(由申请人提供)：在撒哈拉以南非洲， 疟疾是由于接触具有感染性的蚊子叮咬而引起的，尤其是 冈比亚按蚊。在数量上有高度的异质性 住在流行区的人被传染的叮咬，这对 对量化并最终降低传播强度的影响。 我们假设这种异质性是由于成体的聚集生产 蚊子来自幼虫栖息地，这是产卵地点的函数 幼虫的选择和栖息地的产生。我们认为这两个过程 是由出现在幼虫栖息地的微生物介导的。雌性蚊子 将选择产卵地点释放挥发性有机化合物(VOCs)，这 是由蛋白质的微生物代谢产生的(到吲哚及其 衍生物)和腐植酸(到酚类)。第二，我们将量化 幼虫营养物质的微生物处理与微生物生物量的积累 栖息地，并将它们与成体生产联系起来。我们相信 密度依赖的幼虫对营养受限微生物食物的竞争 资源将限制成虫的生产，并将导致紧急的雌性 可变的、次理想的身体质量和营养储备。这些因素将在 进而影响人口调控过程和向量能力属性 在一个。冈比亚亚纲种群。方法将涉及到空间量化 肯尼亚西部阿森博湾研究地点的多产幼虫栖息地 对疟疾流行区进行了彻底的绘制和充分的研究。微生物的调节作用 产卵地点的选择将通过鉴定产卵地点 微生物群落和排放VOCs的GC/MS分析 VOCs的检测和实验产卵地点的微生物选择 挥发性有机化合物是被操纵的。幼虫栖息地生产的微生物基础将是 通过田间和实验室实验研究了营养源和微生物 群落被量化、操纵和幼虫的生长反应和成虫 生产是量化的。

DESCRIPTION: (provided by the applicant): In subSaharan Africa, the risk of malaria is due to exposure to infectious bites of mosquitoes, particularly Anopheles gambiae. There is a high degree of heterogeneity in the number of infectious bites that peoplewho live in endemic areas receive, which has implications for quantifying and ultimately reducing intensity of transmission. We hypothesize that this heterogeneity is due to aggregated production of adult mosquitoes from larval habitats, which is a function of oviposition site selection and larval habitat production. We believe that both of these processes are mediated by microorganisms that occur in larval habitats. Female mosquitoes will choose oviposition sites that emit volatile organic compounds(VOCs), which are generated by microbial metabolism of proteins (to indole and its derivatives) and humic acids (to phenolics). Secondly, we will quantify microbial processing of nutrients and accrual of microbial biomass in larval habitats, and link them to adult production. We believe that density-dependentlarval competition for nutrient-limited microbial food resources will limit adult production and will result in emergent females of variable, suboptimal body masses and nutrient reserves. These factors will in turn affect population regulatory processes and vectorial capacity attributes in An. Gambiae populations. Methods will involve spatial quantification of productive larval habitats in the Asembo Bay study site in western Kenya, a thoroughly mapped and well studied malaria endemic area. Microbial-mediation of oviposition site selection will be studied through characterization of the microbial community and emitted VOCs using GC/MS. GC/MS-electroantennogram detection of VOCs, and experimental oviposition site selection where microbes and VOCs are manipulated. Microbial basis for larval habitat production will be studied with field and lab experiments where nutrient sources and microbial communities are quantified, manipulated and larval growth responses and adult production quantified.