GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, 24105, Kiel, Germany.
Department of Biology, University of Alabama at Birmingham, 1300 University Blvd, CH464, Birmingham, AL, 35294, USA.
ISME J. 2021 Jun;15(6):1668-1679. doi: 10.1038/s41396-020-00878-7. Epub 2021 Jan 21.
Invasive species are co-introduced with microbiota from their native range and also interact with microbiota found in the novel environment to which they are introduced. Host flexibility toward microbiota, or host promiscuity, is an important trait underlying terrestrial plant invasions. To test whether host promiscuity may be important in macroalgal invasions, we experimentally simulated an invasion in a common garden setting, using the widespread invasive macroalga Agarophyton vermiculophyllum as a model invasive seaweed holobiont. After disturbing the microbiota of individuals from native and non-native populations with antibiotics, we monitored the microbial succession trajectories in the presence of a new source of microbes. Microbial communities were strongly impacted by the treatment and changed compositionally and in terms of diversity but recovered functionally by the end of the experiment in most respects. Beta-diversity in disturbed holobionts strongly decreased, indicating that different populations configure more similar -or more common- microbial communities when exposed to the same conditions. This decline in beta-diversity occurred not only more rapidly, but was also more pronounced in non-native populations, while individuals from native populations retained communities more similar to those observed in the field. This study demonstrates that microbial communities of non-native A. vermiculophyllum are more flexibly adjusted to the environment and suggests that an intraspecific increase in host promiscuity has promoted the invasion process of A. vermiculophyllum. This phenomenon may be important among invasive macroalgal holobionts in general.
入侵物种与它们的原生范围中的微生物群落一起共同引入，并且与它们被引入的新环境中的微生物群落相互作用。宿主对微生物群落的灵活性，或宿主的混杂性，是陆地植物入侵的一个重要特征。为了测试宿主的混杂性是否在宏观藻类的入侵中很重要，我们在一个常见的花园环境中进行了实验模拟入侵，使用广泛分布的入侵性大型海藻 Agarophyton vermiculophyllum 作为入侵性海藻共生体的模型。在用抗生素干扰来自原生和非原生种群的个体的微生物群落后，我们监测了在存在新微生物源的情况下微生物的演替轨迹。微生物群落受到处理的强烈影响，在组成和多样性方面发生了变化，但在实验结束时，大多数方面都恢复了功能。受干扰的共生体中的β多样性强烈下降，表明不同种群在暴露于相同条件下配置了更相似（或更常见）的微生物群落。这种β多样性的下降不仅更快，而且在非原生种群中更为明显，而来自原生种群的个体保留的群落与在野外观察到的群落更为相似。这项研究表明，非本地的 Agarophyton vermiculophyllum 的微生物群落更能灵活地适应环境，并表明宿主混杂性的种内增加促进了 Agarophyton vermiculophyllum 的入侵过程。这种现象在一般的入侵性大型藻类共生体中可能很重要。
