High Genetic Diversity With Weak Phylogeographic Structure of the Invasive Spartina alterniflora (Poaceae) in China

作者：Lei Shang, Linfeng Li, Zhiping Song, Yi Wang, Ji Yang, Chuan‐Chao Wang, Shiyun Qiu, Jingxin Huang, Ming Nie, Lorne M. Wolfe, Bo Li · 发表于：Frontiers in Plant Science · 年份：2019 · DOI：10.3389/fpls.2019.01467 · 被引用次数：16 · 研究领域：Plant Taxonomy and Phylogenetics、Plant responses to water stress、Botany, Ecology, and Taxonomy Studies

Biological invasion represents a global issue of concern due to its large negative impacts on native ecosystems and society. Elucidating the evolutionary history and genetic basis underpinning invasiveness is critical to understanding how alien species invade and adapt to novel environments. Smooth cordgrass (Spartina alterniflora, 2n = 6x = 62) is a notorious invasive species that causes heavily negative effects on native ecosystems worldwide. Here we addressed the evolutionary mechanisms underlying the invasion and dispersal history of this species along the China coast in the past decades. We employed nine microsatellites and three chloroplast genes to investigate phylogeographic structure and genetic diversity of 22 native and invasive S. alterniflora populations in United States and China. Demographic history simulation was also performed for both the native and invasive populations, respectively. Comparative genetic analyses of these natural populations revealed that although all the Chinese populations were introduced only once, high level of genetic diversity with weak geographic structure was observed. In particular, both the genetic features and mathematical simulation illustrated very recent population expansion in the Chinese populations. In addition, we found that genetic variants identified in native US populations were mixed in the Chinese populations, suggesting the recombination of these original variants during the invasion process. These genetic attributes ...