Genetic diversity and ecological success of the invasive riparian plant Mimulus guttatus

对生物入侵的研究可以帮助我们设计有效的策略来预防和管理入侵物种。与河流和溪流相关的栖息地特别容易受到生物入侵，这既是因为它们受到自然干扰，也是因为它们经常受到相当大的人为修改。河流和溪流网络促进了入侵物种的扩散，这可能会加剧它们的负面影响，并使它们的控制成为一项具有挑战性的任务。事实上，英国一些最著名的入侵植物物种与水体密切相关(例如喜马拉雅香脂、巨型猪草、日本虎尾草)。尽管在英国研究生物入侵有很长的历史，但在入侵河岸物种的遗传变异结构方面仍存在很大的知识空白。种群内和种群间的遗传变异分布包含了大量关于入侵物种引进和传播的历史、它们之间的遗传联系程度以及最终入侵物种在不断变化的环境条件下继续适应新环境并促进其传播的潜力的信息。阐明这些生物模式是设计持久和成功的应对生物入侵策略的必要的第一步。我们的研究重点是黄猴花(Mimulus Guttatus)，这是一种广泛存在的入侵植物，主要局限于永久性和临时性的自来水水体。它通过种子进行有性繁殖，也通过水携带的植物碎片进行无性繁殖。猴子花是在19世纪初从北美引进英国的S，目前在不列颠群岛随处可见。猴花非常适合研究入侵期间的遗传和进化过程。在过去的50年里，猴花的生态和进化在其原生范围内得到了广泛的研究，它已经成为当地适应、种群结构、繁殖策略、物种形成和基因组学研究的模式。没有其他英国入侵的河岸植物拥有类似的资源，这使得点滴菊属成为研究入侵物种生态遗传学的明显选择。在这里，我们将从广泛的地理尺度到小的种群内水平研究入侵河岸植物的空间遗传结构。在这项工作的第一部分，我们将在不同的空间尺度上对英国各地的40个猴花种群进行采样，从广阔的地理区域到流域内的多个种群。这一部分产生的数据将使我们能够确定英国猴花的一般遗传结构，检验该物种在这里的殖民和传播模式的相互矛盾的假说，并测量空间尺度上的遗传连通性。在这项工作的第二部分，我们将在精细空间尺度上进行采样，以估计有性繁殖和无性繁殖的比率，这是入侵物种动态的基本决定因素。这些数据将使我们第一次计算无性繁殖对遗传变异结构的重要性，以及它与入侵猴花生态成功的关系。通过将遗传分析与生态成功的测量相结合，我们将推断入侵的历史模式和种群之间的联系，并揭示繁殖模式是否与整体遗传多样性和生态成功相关。我们的项目为在英国建立猴子花作为研究生物入侵的模型提供了一个特殊的机会。这一领先的项目将为未来在英国和其他地方开展入侵物种的生态、进化和管理工作奠定基础。

The study of biological invasions can help us to design effective strategies to prevent, and manage invasive species. Habitats associated with rivers and streams are particularly susceptible to biological invasion, both because of their natural levels of disturbance and because they are often subject of considerable man-made modification. Networks of river and streams facilitate the dispersal of invasive species which can potentiate their negative effects and make their control a challenging task. In fact, some of the most prominent invasive plant species in the UK occur in close association with water bodies (e.g. Himalayan balsam, giant hogweed, Japanese knotweed). Despite a long history of studying biological invasions in the UK, large gaps of knowledge exist in the structure of genetic variation of invasive riparian species. The distribution of genetic variation both within and between populations holds a trove of information regarding the history of introduction and spread of invasive species, the extent of genetic connectivity among them, and ultimately the potential of invasive species to keep adapting to novel environments and advance their spread under changing environmental conditions. Elucidating these biological patterns is the necessary first step towards designing lasting and successful strategies to deal with biological invasions.Our study focuses on yellow monkey flowers (Mimulus guttatus), a widespread invasive plant that is mostly restricted to permanent and temporary bodies of running-water. It propagates both sexually via seeds and asexually through plant fragments carried by water. Monkey flowers were introduced to the UK from North America in the early 1800's, and are currently found throughout the British Isles. Monkey flowers are excellently suited for studying genetic and evolutionary processes during invasions. The ecology and evolution of monkey flowers has been extensively studied in its native range during the past 50 years, where it has become a model for studies of local adaptation, population structure, reproductive strategies, speciation, and genomics. No other UK invasive riparian plant has similar resources readily available, making M. guttatus the obvious choice for studying the ecological genetics of invasive species.Here we will investigate the spatial genetic structure on an invasive riparian plant from broad geographic scales to small, within-population levels. In the first component of the work we will sample 40 populations of monkey flowers across the UK at different spatial scales from broad geographic regions to multiple populations within water catchments. The data generated in this component will allow us to determine the general genetic structure of monkey flowers in Britain, to test competing hypothesis of the pattern of colonization and spread of this species here, and to measure genetic connectivity across spatial scales. In the second component of the work we will sample at the fine spatial scale to estimate the rates of sexual and asexual reproduction, which is a fundamental determinant of the dynamics of invasive species. These data will allow us to calculate for the first time, the importance of asexual propagation to the structure of genetic variation and its relationship with ecological success in invasive monkey flowers. By combining genetic analyses with measurements of ecological success, we will infer historical patterns of invasion and connectivity between populations, and reveal whether the mode of reproduction correlates both with overall genetic diversity and ecological success.Our project provides an exceptional opportunity to establish monkey flowers as a model for the study of biological invasions in the UK. This leading project will set the stage for future work on the ecology, evolution and management of invasive species in the UK and elsewhere.