Population genetic dynamics of Himalayan-Hengduan tree peonies, Paeonia subsect. Delavayanae
作 者：Zhang JM, Lopez-Pujol J*, Gong X, Wang HF, Vilatersana R, Zhou SL*
影响因子:4.419
刊物名称:Molecular Phylogenetics and Evolution
出版年份:2018
卷:125期: 页码:62-77
文章摘要:According to the present taxonomical treatment,Paeoniasubsect.Delavayanaeconsists of only two species (P. delavayiandP.ludlowii) endemic to the Himalayan-Hengduan Mountains. AlthoughP. ludlowiican be distinguished fromP. delavayion the basis of a series of morphological characters, the species delimitation remains controversial because the more widespread one,P. delavayi, exhibits considerable morphological diversity. BothchloroplastDNA markersand nuclearmicrosatellitesor simple sequence repeats (nSSR) are used herein to reveal genetic diversity and relationships of the two taxa included in this subsection, and ecological niche modeling (ENM) is employed to get insights into their paleodistribution. Our results show that genetic boundaries between the two currently recognized species are unclear, probably due to recent divergence.Paeonia ludlowiiis budding fromP. delavayi, probably by genetic isolation but also by shifting its niche to the harsher upland Tibetan conditions.Paeonia delavayiitself would be, however, under active speciation, showing significantgenetic differentiationand morphological diversity. WhereasP. ludlowiiwould have endured the Pleistocene glacial periods byin situpersistence in local, small refugia, a ‘dual’ model seems to apply forP. delavayi(in situpersistence and retreat to refugia). The rarity ofP. ludlowiiand high evolutionary potential ofP. delavayiimply high priority forin situconservation of both taxa. The Himalayan-Hengduan Mountains are an ideal arena for differentiation within subsect.DelavayanaeofPaeonia, by means of expansions/contractions/displacements,vertical migrations, and local survival/extinctions in response to the Neogene climate fluctuations and geological changes.