Potential refugium on the Qinghai-Tibet Plateau revealed by the chloroplast DNA phylogeography of the alpine species Metagentiana striata (Gentianaceae)
Potential refugium on the Qinghai-Tibet Plateau revealed by the chloroplast DNA phylogeography of the alpine species Metagentiana striata (Gentianaceae)
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DOI：
10.1111/j.1095-8339.2008.00785.x
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发表时间：
2008-05-01
影响因子：
2.4
通讯作者：
Chen, Shilong
中科院分区：
文献类型：
--
作者：
Chen, Shengyun;Wu, Guili;Chen, Shilong
条斑绿苔（Metagentiana striata）是青藏高原东部及邻近地区特有的一种高山一年生草本植物。M.利用叶绿体DNA（cpDNA）trnS-trnG基因间隔区序列测定方法，对中国对虾的叶绿体DNA序列进行了研究。通过对232个个体的调查，共鉴定出10种单倍型。striata从14个种群覆盖本种的整个地理范围。居群间分化程度很高（G（ST）= 0.746; N-ST = 0.774），地理结构呈明显的连锁性（P < 0.05）。分子方差分析发现，居群间变异较大（76%），F-ST = 0.762（极显著，P < 0.001），表明不同地区间基因流较少;这是由于沿着青藏高原和邻近地区的高山隔离了居群（N-m = 0.156）。只有一个祖先单倍型（A）是常见的，并广泛分布在整个分布范围的M。纹状体。青藏高原东南部横断山区居群具有较高的单倍型多样性和独特性。这表明该地区可能是M. striata在第四纪冰期，间冰期和冰后期的范围扩大发生从这个避难所。这种情况与巢式进化枝分析的结果非常一致，巢式进化枝分析推断cpDNA单倍型和种群当前的空间分布是由范围扩张以及过去的异地片段化事件造成的。(c)2008年，伦敦林奈学会。
Metagentiana striata is an alpine annual herbaceous plant endemic to the east of the Qinghai-Tibet (Q-T) Plateau and adjacent areas. The phylogeography of M. striata was studied by sequencing the chloroplast DNA (cpDNA) trnS-trnG intergenic spacer. Ten haplotypes were identified from an investigation of 232 individuals of M. striata from 14 populations covering the entire geographical range of this species. The level of differentiation amongst populations was very high (G(ST) = 0.746; N-ST = 0.774) and a significant phylogeographical structure was observed (P < 0.05). An analysis of molecular variance found a high variation amongst populations (76%), with F-ST = 0.762 (highly significant, P < 0.001), indicating that little gene flow occurred amongst the different regions; this was explained by the isolation of populations by high mountains along the Q-T Plateau and adjacent areas (N-m = 0.156). Only one ancestral haplotype (A) was common and widespread throughout the distributional range of M. striata. The populations of the Hengduan Mountains region of the south-eastern Q-T Plateau showed high diversity and uniqueness of haplotypes. It is suggested that this region was the potential refugium of M. striata during the Quaternary glaciation, and that interglacial and postglacial range expansion occurred from this refugium. This scenario was in good agreement with the results of nested clade analysis, which inferred that the current spatial distribution of cpDNA haplotypes and populations resulted from range expansion, together with past allopatric fragmentation events. (c) 2008 The Linnean Society of London.