Is the Baekdudaegan “the Southern Appalachians of the East”? A comparison between these mountain systems, focusing on their role as glacial refugia

11 p., mapas, tablasBased on genetic studies and palaeoecological surveys, the main Korean mountain range, the so- called “Baekdudaegan” (BDDG), has been recently suggested to be a major glacial refugium at the Last Glacial Maximum (LGM) for the boreal and temperate flora of northeastern Asia. On the basis of its shared role as a glacial refugium, and on a series of striking similarities in floristic richness and orographic features, the BDDG would constitute a sort of “eastern counterpart” of the Southern Appalachians. Given its floristic, biogeo- graphic, and cultural value, the BDDG merits high priority for conservation.This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF- 2013R1A1A2063524 and NRF-2013R1A1A3010892 to M.G.C. and M.Y.C., respectivelyPeer reviewe

Population genetic structure of Sedum polytrichoides (Crassulaceae): Insights into barriers to gene flow

10 p., tablas, gráf.An area comprising Juwangsan National Park and its adjacent mountains (southeastern Korean Pen- insula) is a good model system for testing the effects of physical barriers to gene flows in plant populations. We predicted that plant species consisting of isolated populations are genetically more differentiated than those that are rather continuously distributed. Most populations of Sedum polytrichoides occur in four isolated valleys, and we assessed the genetic variability and structures using twelve allozyme loci in ten populations. We also com- pared the present results to earlier findings pertaining to the two co-occurring herbs Hylotelephium ussuriense (≡ Sedum ussuriense) (growing only in the four isolated valleys) and S. kamtschaticum (rather continuously dis- tributed). We found moderate levels of within-population genetic variation in S. polytrichoides (H = 0.112). Estimates of among-population divergence in S. polytrichoides were also moderate (F = 0.250) and, as expected, very similar to that of H. ussuriense (0.261) but considerably higher than the variation in S. kamtschat- icum (0.165). An analysis of molecular variance (AMOVA) revealed that S. polytrichoides and H. ussuriense had higher percentages of among-valley variation (19% each) than S. kamtschaticum (4%). Most of this vari- ation, as also indicated by the STRUCTURE program, was due to differences in genetic profiles between the two central valleys. We concluded that the genetic differences observed between species (S. kamtschaticum vs. S. polytrichoides and H. ussuriense) are mainly due to differences in their distribution within the study area.This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2013R1A1A2063524 and NRF-2013R1A1A3010892 to M.G.C. and M.Y.C., respectivelyPeer reviewe

The Korean Baekdudaegan Mountains: A Glacial Refugium and a Biodiversity Hotspot That Needs to Be Conserved

The Baekdudaegan (BDDG; Figure 1) is a mountain range relatively unknown outside Korea. From recent times, however, the BDDG is known outside Korea because it shelters the small county of Pyeongchang, the venue of the 2018 Winter Olympic Games.This research was supported by Korea Research Foundation grants; KRF-2013R1A1A2063524 to MYC and NRF-2011-0017236, NRF-2013R1A1A3010892, and NRF-2017R1A2B4012215 to MGC and was carried out as part of the Infrastructure for the Conservation and Restoration of Rare and Endemic Plants in Korea National Arboretum that supported to MGC from 2015 to 2018.Peer reviewe

Blow to the northeast? Intraspecific differentiation of populus davidiana suggests a northeastward skew of a phylogeographic break boundary in East Asia

Aim There is increasing interest in the role that biological traits, and historical and biogeographic processes, play in the formation of phylogeographic patterns. An arid belt that once existed in northern China might have affected many plants, but this has yet to be tested in an arid-tolerant, wind-dispersed species. Here, we tested how intrinsic and extrinsic factors have affected the phylogeography of Populus davidiana. Location East Asia. Methods Genetic variation was surveyed across 40 populations (555 individuals) covering the Chinese range of P. davidiana, using 16 nuclear microsatellite loci (nSSRs) and four chloroplast fragments (cpDNA). Demographic and migration hypotheses were tested using coalescent-based approaches, and the present and past potential distributions were predicted using species distribution modelling. Results Molecular data divide P. davidiana into two lineages, north-eastern China (NECR) and central and northern China (CNCR); however, the dividing line is around 118ºE for nSSRs, but 122ºE for cpDNA. The range and habitat of the two lineages barely overlap at present, and their ecological separation may have initiated around the Pliocene-Quaternary boundary, when major intraspecific cpDNA clades diverged. NECR and CNCR experienced post-glacial north-eastward and northward range shifts respectively. Bi-directional historical gene flow was detected between NECR and CNCR for both bi-parentally inherited nSSRs and maternally inherited cpDNA. Demographic inferences suggest a severe bottleneck for CNCR and especially NECR, around the latest Pleistocene. Main conclusions The phylogeographic break within P. davidiana reflects the impacts of biogeographic history, climate and biological traits. Its plumed, wind-dispersed seeds might be especially significant because prevailing south-western spring winds may have moved the NECR-CNCR boundary further east than similar phylogenetic breaks in other species, and also moved the cpDNA boundary relative to that for nuclear markers. Biological traits, therefore, should also be considered when examining the genetic and ecological differentiation between closely related taxa

Phylogeny and biogeography of Fagus (Fagaceae) based on 28 nuclear single/low-copy loci

Fagus L. is a key component in temperate deciduous broadleaf forests of the Northern Hemisphere. However, its biogeographic history has not been examined under the framework of a fully resolved and reasonably time-calibrated phylogeny. In this study, we sequenced 28 nuclear single/low-copy loci (18 555 bp in total) of 11 Fagus species/segregates and seven outgroups. Phylogenetic trees were reconstructed using both concatenation-based (maximum parsimony, maximum likelihood, and Bayesian inference) and coalescent-based methods (StarBEAST2, ASTRAL). The monophyly of two subgenera (Fagus and Engleriana) and most sections was well supported, except for sect. Lucida, which was paraphyletic with respect to sect. Longipetiolata. We also found a major phylogenetic conflict among North American, East Asian, and West Eurasian lineages of subgen. Fagus. Three segregates that have isolated distribution (F. mexicana, F. multinervis, and F. orientalis) were independent evolutionary units. Biogeographic analysis with fossils suggested that Fagus could have originated in the North Pacific region in late early Eocene. Major diversifications coincided with a climate aberration at the Eocene/Oligocene boundary and the global cooling since mid-Miocene. The late Miocene accelerated global cooling and the Pleistocene glaciations would have driven beeches into East Asia, North America, and West Eurasia. Meanwhile, range reduction and extinction in high latitudes, central Asia, and western North America converged to form the beech modern distribution pattern. This study provides a first attempt to disentangle the biogeographic history of beeches in the context of a nearly resolved and time-calibrated phylogeny, which could shed new insights into the formation of the temperate biome in the Northern Hemisphere.This work was supported by the National Natural Science Foundation of China (Grant Nos. 31770236, 30760016, and 31560064) and the Strategic Priority Research Program of Chinese Academy of Sciences (XDB31000000).1 Introduction 2 Material and Methods 2.1 Taxon sampling 2.2 Screening of nuclear single/low-copy orthologous locus 2.3 DNA extraction, PCR protocol, and sequencing 2.4 Phylogenetic analyses and molecular dating 2.5 Ancestral area reconstruction 3 Results 3.1 Concatenated tree 3.2 Species tree and molecular dating 3.3 Ancestral area reconstruction 4 Discussion 4.1 Nearly resolved and well supported phylogeny of Fagus 4.2 Species delimitation of three segregates within Fagus 4.3 Biogeographic history of beech species Acknowledgement