基于叶绿体DNA的黄土高原特有植物蕤核的谱系地理学

该文利用母系遗传的叶绿体DNA片段(psb A-trn H,psb I-psb K和psb J-pet A)对黄土高原地区的特有植物蕤核(Prinsepia uniflora)进行谱系地理学研究,以揭示其现有的遗传结构和群体历史动态。结果表明:(1)蕤核自然种群总的遗传多样性较高(H_T=0.796),而种群内的遗传多样性较低(H_S=0.276)。(2)分子变异分析(AMOVA)表明,分布区域内蕤核具有较高的遗传分化(F_(ST)=0.674),且遗传变异主要存在于种群间(67.4%)。(3) Mismatch分析和基于Max Ent的不同历史时期生态位模拟结果表明,尽管蕤核的核心适生范围没有经历太大的变化,但其种群在最后一次大冰期结束后仍存在一定程度上的扩张。综上结果认为,与大多数分布在我国北方地区的许多植物类群一样,蕤核很可能是采取冰期在邻近或者就地避难,冰期过后局部回迁的方式应对第四纪的气候波动。

Phylogeography of the Loess Plateau endemic plant Prinsepia uniflora inferred from the chloroplast DNA

To reveal the historical dynamics of the population and existing genetic structure, maternal chloroplast DNA fragments(psbA-trnH, psbI-psbK and psbJ-petA)were used to study the phylogeography of Prinsepia uniflora, a kind of endemic plant distributed in the Loess Plateau. The results were as follows:(1)Total genetic diversity of P. uniflora was high(H_T = 0.796), but genetic diversity within species was low(H_S= 0.276);(2)The molecular variation analysis(AMOVA)showed that there was a high genetic differentiation within P. uniflora(F_ST = 0.674), and the genetic variation was mainly between populations(67.4%);(3)Mismatch analysis and MaxEnt based ecological niche simulation results in different historical periods showed that although the core suitable range of P. uniflora did not change much, population still expanded to some extent after the end of the Last Glacial Maximum(LGM). Our study indicated that, like most of the plant groups distributed in the northern regions of China, P. uniflora probably responded to the Quaternary climatic fluctuations by taking refuge nearby or in situ during the glacial period and locally recolonizing in following post-glacial period.