Diversification and historical demography of Haloxylon ammodendron in relation to Pleistocene climatic oscillations in northwestern China

PeerJ

article

Yuting Chen¹  Songmei Ma¹  Dan Zhang²  Bo Wei³  Gang Huang²  Yunling Zhang⁴  Benwei Ge¹ 

[1] Shihezi University, Xinjiang Production and Construction Corps Key Laboratory of Oasis Town and Mountain-basin System Ecology, College of Science;Shihezi University, Xinjiang Production and Construction Corps Key Laboratory of Oasis Town and Mountain-basin System Ecology, College of Life Sciences;Institute of Geographic Sciences and Natural Resources Research;General Grassland Station of Xinjiang

关键词: Haloxylon ammodendron;    Allopatric divergence;    Refugia;    Demographic history;    China introduction;   

DOI  :  10.7717/peerj.14476

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

The influence of aridification and climatic oscillations on the genetic diversity and evolutionary processes of organisms during the Quaternary in northwestern China is examined using Haloxylon ammodendron. Based on the variation of two cpDNA regions (trnS-trnG and trnV) and one nDNA sequence (ITS1-ITS4) in 420 individuals from 36 populations, the spatial genetic structure and demographic history of H. ammodendron in arid China is examined. Median-joining network and Bayesian inference trees enabled the identification of three diverged lineages within H. ammodendron from 24 different haplotypes and 16 ribotypes, distributed across western (Xinjiang), eastern (Gansu and Inner Mongolia) and southern (Qinghai) regions. AMOVA analysis demonstrated that more than 80% of observed genetic variation related to lineage split was based on cpDNA and nDNA variation. Allopatric divergence among the three groups was mainly triggered by geographical isolation due to Xingxingxia rock and uplift of the Qilian Mountains during the Quaternary. Local adaptive differentiation among western, eastern and southern groups occurred due to gene flow obstruction resulting from arid landscape fragmentation accompanied by local environmental heterogeneity of different geographical populations. The southern margin of the Junggar Basin and the Tengger Desert possibly served as two independent glacial refugia for H. ammodendron. The distribution of genetic variation, coupled with SDMs and LCP results, indicated that H. ammodendron probably moved northward along the Junggar Basin and westward along Tengger Desert at the end of the last glacial maximum; postglacial re-colonization was probably westward and southward along the Hexi Corridor.

【 授权许可】

CC BY