Edaphic specialization is one of the main drivers of plant diversification and has multifaceted effects on population dynamics. Carex angustisquama is a sedge plant growing only on heavily acidified soil in solfatara fields, where only extremophytes can survive. Because of the lack of closely related species in similar habitats and its disjunct distribution, the species offers ideal settings to investigate the effects of adaptation to solfatara fields and of historical biogeography on the genetic consequences of plant edaphic specialization to solfatara fields. Here, genome‐wide single nucleotide polymorphisms were used to reveal the phylogenetic origin of C. angustisquama, and 16 expressed sequence tag–simple sequence repeat markers were employed to infer population demography of C angustisquama. Molecular phylogenetic analysis strongly indicated that C. angustisquama formed a monophyletic clade with Carex doenitzii, a species growing on nonacidified soil in the sympatric subalpine zone. The result of population genetic analysis showed that C. angustisquama has much lower genetic diversity than the sister species, and notably, all 16 loci were completely homozygous in most individuals of C. angustisquama. Approximate Bayesian computation analysis supported the model that assumed hierarchical declines of population size through its evolutionary sequence. We propose that the edaphic specialist in solfatara fields has newly attained the adaptation to solfatara fields in the process of speciation. Furthermore, we found evidence of a drastic reduction in genetic diversity in C. angustisquama, suggesting that the repeated founder effects associated with edaphic specialization and subsequent population demography lead to the loss of genetic diversity of this extremophyte in solfatara fields.

中文翻译：

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植物土壤专业化对 solfatara 领域的遗传后果：Carex angustisquama（莎草科）的系统发育和种群遗传分析。

土壤专业化是植物多样化的主要驱动力之一，对种群动态具有多方面的影响。Carex angustisquama是一种莎草植物，仅生长在 solfatara 田地中严重酸化的土壤上，只有极端植物才能生存。由于在相似生境中缺乏密切相关的物种及其分散分布，该物种为研究对 solfatara 田地的适应和历史生物地理学对植物土壤专业化对 solfatara 田地的遗传后果的影响提供了理想的环境。在这里，全基因组单核苷酸多态性被用来揭示C. angustisquama的系统发育起源，并使用 16 个表达的序列标签 - 简单序列重复标记来推断 C. angustisquama 的种群人口统计学。角鳞甲。分子系统发育分析强烈表明C. angustisquama与 Carex doenitzii形成了一个单系进化枝，Carex doenitzii是一种生长在同域亚高山地区非酸化土壤上的物种。群体遗传分析结果表明，C. angustisquama的遗传多样性远低于姊妹种，值得注意的是，在C. angustisquama的大多数个体中，所有 16 个位点都是完全纯合的。. 近似贝叶斯计算分析支持通过其进化序列假设种群规模分级下降的模型。我们认为solfatara领域的土壤专家在物种形成过程中新获得了对solfatara领域的适应。此外，我们发现了C. angustisquama遗传多样性急剧减少的证据，这表明与土壤专业化和随后的人口人口学相关的重复创始人效应导致这种极端植物在 solfatara 领域的遗传多样性丧失。