Climate oscillation during the Quaternary associated with landscape heterogeneity promoted allopatric lineage divergence of a temperate tree Kalopanax septemlobus (Araliaceae) in East Asia.
We investigated the biogeographic history of Kalopanax septemlobus, one of the most widespread temperate tree species in East Asia, using a combined phylogeographic and palaeodistribution modelling approach. Range-wide genetic differentiation at nuclear microsatellites (G'(ST) = 0.709; 2205 samples genotyped at five loci) and chloroplast DNA (G(ST) = 0.697; 576 samples sequenced for 2055 bp at three fragments) was high. A major phylogeographic break in Central China corresponded with those of other temperate species and the spatial delineation of the two temperate forest subkingdoms of East Asia, consistent with the forests having been isolated within both East and West China for multiple glacial-interglacial cycles. Evidence for multiple glacial refugia was found in most of its current range in China, South Japan and the southernmost part of the Korean Peninsula. In contrast, lineage admixture and absence of private alleles and haplotypes in Hokkaido and the northern Korean Peninsula support a postglacial origin of northernmost populations. Although palaeodistribution modelling predicted suitable climate across a land-bridge extending from South Japan to East China during the Last Glacial Maximum, the genetic differentiation of regional populations indicated a limited role of the exposed sea floor as a dispersal corridor at that time. Overall, this study provides evidence that differential impacts of Quaternary climate oscillation associated with landscape heterogeneity have shaped the genetic structure of a wide-ranging temperate tree in East Asia.
Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Kyoto 6068502, Japan. sakaguci@kais.kyoto-u.ac.jp
Shota
S
Sakaguchi
Ying-Xiong
YX
Qiu
Yi-Hui
YH
Liu
Xin-Shuai
XS
Qi
Sea-Hyun
SH
Kim
Jingyu
J
Han
Yayoi
Y
Takeuchi
James R P
JR
Worth
Michimasa
M
Yamasaki
Shogo
S
Sakurai
Yuji
Y
Isagi
D005075:Biological Evolution; D002467:Cell Nucleus / Q000235:genetics; D002980:Climate; D018742:DNA, Chloroplast / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D005202:Asia, Eastern; D014644:Genetic Variation; D005828:Genetics, Population; D005843:Geography; D006239:Haplotypes; D036882:Kalopanax / Q000145:classification / Q000235:genetics*; D018895:Microsatellite Repeats; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010802:Phylogeny; D058974:Phylogeography; D014197:Trees / Q000145:classification / Q000235:genetics
D018742:DNA, Chloroplast; D018744:DNA, Plant