The Hengduan Mountains (henceforth H-D Mountains) on the Tibet Plateau are a distribution and diversity center for many alpine genera. We examine patterns of genetic variation in an arctic-alpine plant to evaluate the possibility that the H-D Mountains constitute the area of origin of the species as well as to uncover postglacial migration routes. 220 individuals of the arctic-alpine plant Koenigia islandica were sampled from 26 populations distributed in western China and northern Finland. DNA haplotypes were identified using restriction site analysis of two chloroplast DNA intergene spacer regions, atpB-rbcL and trnL-trnF. We examined the geographical distribution of haplotype diversity in relation to latitude, and also compared various indices of diversity in putatively glaciated and unglaciated regions. Patterns of migration were inferred using nested clade analysis. A total of 25 haplotypes were detected. High haplotype diversity was found in the H-D Mountains. H3 and its radiated haplotypes were distributed in the Himalayas. Two haplotypes were fixed concurrently in the H-D Mountains and northern Finland. High genetic diversity of K. islandica and high species diversity of K. islandica are expected in the origin area. Our observations suggest that the H-D Mountains are not only the place of origin of K. islandica, but also the refugia for K. islandica on the Tibet Plateau. What is more, the migration route for the arctic-alpine plant K. islandica must have originated in the region defined by the H-D Mountains in western China extending northward to the Arctic circumpolar, and moved westward along the Himalayas, then northward across the Altay Mountains and the Central Siberian Plateau at different time periods.
1.Anhui Univ, Anhui Biodivers Informat Ctr, Sch Resources & Environm Engn, Hefei 230601, Peoples R China 2.West Anhui Univ, Dept Biol & Pharmaceut Engn, Liuan 237012, Peoples R China 3.Chinese Acad Sci, Kunming Inst Bot, Key Lab Plant Div & Biogeog East Asia, Kunming 650204, Peoples R China 4.Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China 5.Chinese Acad Sci, Nanjing Inst Geol & Palaeontol, Nanjing 210008, Jiangsu, Peoples R China
Long Cong;Min YunJiang;Zhao XiuXia;Yany ChunLei;Sun Hang;Lu HouYuan;Tang LingYu;Zhou ZhongZe.Origin area and migration route: Chloroplast DNA diversity in the arctic-alpine plant Koenigia islandica,SCIENCE CHINA-EARTH SCIENCES,2014,57(8):1760-1770