Limited data are available on genetic structures of the herbaceous plant species populations inhabiting mountainous areas of Siberia and Northeastern Asian (Russian Far East). Although this area was not directly impacted by the extensive ice-sheets during the Quaternary, it experienced significant climatic fluctuations that influenced rich local flora. Orostachys spinosa (Crassulaceae) lacks any adaptations for long-distance dispersal, yet the species is characterized by an unusually wide range spanning from the Urals to the coast of the Pacific Ocean. We studied O. spinosa phylogeography and genetic diversity across its range sampling 203 individuals from 21 natural populations. Using sequences from three chloroplast DNA non-coding regions, we revealed 82 haplotypes and observed high level of population differentiation indicating presence of the phylogeographic structure (GST = 0.501 and NST = 0.822 (p < 0.01)). In concordance with the previous phylogenetic analyses based on ITS rDNA data, parsimony network revealed two distinct cpDNA haplotype lineages deferring in their structure and characteristics of genetic diversity. The split between these haplotype groups can be dated to the Pliocene (ca. 3.6 Mya). According to our estimates diversification in the Western group of populations took place ca. 1 Mya earlier than in the Eastern group (3.1 Mya and 2.26 Mya, respectively). Apart from the generally accepted notion about East Asian origin of O. spinosa, our results indicated that the species could have originated in mountains of Southern Siberia (Altai). This region was colonized independently from O. thyrsiflora which has a largely overlapping distribution in this area.

中文翻译：

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Orostachys spinosa（景天科）起源和多样化：东亚还是南西伯利亚山脉？叶绿体 DNA 数据

关于居住在西伯利亚和东北亚（俄罗斯远东）山区的草本植物种群的遗传结构数据有限。虽然该地区在第四纪没有直接受到大面积冰盖的影响，但它经历了显着的气候波动，影响了当地丰富的植物群。Orostachys spinosa（景天科）对长距离传播缺乏任何适应性，但该物种的特点是从乌拉尔到太平洋沿岸的范围异常广泛。我们从 21 个自然种群中抽取了 203 个个体，研究了其范围内的 O. spinosa 系统地理学和遗传多样性。使用来自三个叶绿体 DNA 非编码区的序列，我们揭示了 82 个单倍型并观察到高水平的种群分化，表明存在系统地理学结构（GST = 0.501 和 NST = 0.822 (p < 0.01)）。与之前基于 ITS rDNA 数据的系统发育分析一致，简约网络揭示了两个不同的 cpDNA 单倍型谱系，其结构和遗传多样性特征有所不同。这些单倍型组之间的分裂可以追溯到上新世（约 3.6 Mya）。根据我们的估计，西方人群的多样化发生在大约。1 Mya 早于东部组（分别为 3.1 Mya 和 2.26 Mya）。除了普遍接受的关于 O. spinosa 东亚起源的概念外，我们的结果表明该物种可能起源于西伯利亚南部（阿尔泰）的山区。