title: Genetic structure and phylogeography of a temperate-boreal herb, Cardamine scutata (Brassicaceae), in northeast Asia inferred from AFLPs and cpDNA haplotypes.
abstract: OBJECTIVE
  Studies on genetic structure of plant populations help us understand the history of local flora and vegetation. In this study, we focus on the temperate-boreal herb Cardamine scutata from northeast Asia, an area with scarce phylogeographic studies. We explore patterns of genetic variation within this species, with an aim to infer its (post-) glacial history with reference to colonization routes and migrations via land bridges. •
  
  
  METHODS
  We analyzed 46 populations sampled in Japan, Kamchatka, and Korea using AFLP and cpDNA sequence data. •
  
  
  RESULTS
  Two intraspecific genetic groups were resolved, distributed in the northeastern and southwestern part of the study area, most likely reflecting lineages isolated from each other during (at least) the last glaciation. A zone of secondary contacts was found in central/northern Honshu, and a few cases of long-distance dispersal were observed. We detected efficient gene flow across the marine straits, supporting the role of land bridges created by sea level decline during the last glacial period. The cpDNA data indicated extensive recent expansion and diversification within both lineages. We inferred recent colonization of Kamchatka from Hokkaido, associated with genetic impoverishment. •
  
  
  CONCLUSIONS
  The pattern of north-south genetic differentiation found in C. scutata is rather common among several other plant species studied in Japan, despite their distinct biological features. We assume that different processes and factors may have brought about this similarity. Overall, this study contributes to better understanding of the biogeography of northeast Asia.
authors.affiliation: Institute of Botany, Slovak Academy of Sciences, Dúbravská cesta 9, SK-845 23 Bratislava, Slovak Republic.
authors.forename: Judita
authors.initials: J
authors.lastname: Lihová
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kudoh
authors.forename: Karol
authors.initials: K
authors.lastname: Marhold