Tian Xiang-Yu, Ye Jun-Wei, Wang Tian-Ming, Bao Lei, Wang Hong-Fang
State Key Laboratory of Earth Surface Processes and Resource Ecology and Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life Sciences Beijing Normal University Beijing China.
Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Kunming China.
Ecol Evol. 2020 Mar 24;10(10):4331-4342. doi: 10.1002/ece3.6200. eCollection 2020 May.
Isolation by spatial distance (IBD), environment (IBE), and historical climatic instability (IBI) are three common processes assessed in phylogeographic and/or landscape genetic studies. However, the relative contributions of these three processes with respect to spatial genetic patterns have seldom been compared. Moreover, whether the relative contribution differs in different regions or when assessed using different genetic markers has rarely been reported. has been found to have two sister genetic clades of chloroplast (cpDNA) and nuclear microsatellite (nSSR), both of which show discontinuous distribution in northern and southern East Asia. In this study, we used the Mantel test and multiple matrix regression with randomization (MMRR) to determine the relative contributions of IBD, IBE, and IBI with respect to populations. Independent Mantel tests and MMRR calculations were conducted for two genetic data sets (cpDNA and nSSR) and for different regions (the overall species range, and northern and southern subregions of the range). We found a significant IBI pattern in nSSR divergence for all assessed regions, whereas no clear IBI pattern was detected with respect to cpDNA. In contrast, significant (or marginal) divergent IBD patterns were detected for cpDNA in all regions, whereas although a significant IBE was apparent with respect to the overall range, the effect was not detected in the two subregions. The differences identified in nSSR and cpDNA population divergence may be related to differences in the heredity and ploidy of the markers. Compared with the southern region, the northern region showed less significant correlation patterns, which may be related to the shorter population history and restricted population range. The findings of this study serve to illustrate that comparing between markers or regions can contribute to gaining a better understanding the population histories of different genomes or within different regions of a species' range.
通过空间距离隔离（IBD）、环境隔离（IBE）和历史气候不稳定性隔离（IBI）是系统地理学和/或景观遗传学研究中评估的三个常见过程。然而，这三个过程对空间遗传模式的相对贡献很少被比较。此外，很少有报道称相对贡献在不同区域或使用不同遗传标记进行评估时是否存在差异。已发现 有叶绿体（cpDNA）和核微卫星（nSSR）的两个姐妹遗传分支，两者在东亚北部和南部均呈不连续分布。在本研究中，我们使用曼特尔检验和随机化多重矩阵回归（MMRR）来确定IBD、IBE和IBI对 种群的相对贡献。针对两个遗传数据集（cpDNA和nSSR）以及不同区域（整个物种分布范围以及该分布范围的北部和南部分区域）进行了独立的曼特尔检验和MMRR计算。我们发现，在所有评估区域中，nSSR分歧存在显著的IBI模式，而对于cpDNA未检测到明显的IBI模式。相反，在所有区域中cpDNA均检测到显著（或边缘）的分歧IBD模式，而尽管在整个分布范围内明显存在显著的IBE，但在两个子区域中未检测到该效应。nSSR和cpDNA种群分歧中发现的差异可能与标记的遗传和倍性差异有关。与南部地区相比，北部地区的相关模式不太显著，这可能与较短的种群历史和有限的种群范围有关。本研究结果表明，比较不同标记或区域有助于更好地理解不同基因组或物种分布范围内不同区域的种群历史。
