We hypothesized that the main Korean mountain ranges provided many refugia for boreal plant species, where they likely found relatively stable habitats and maintained large population sizes. Under this scenario, high levels of genetic variation and low degree of differentiation among populations within these species were anticipated. To test this hypothesis, we examined levels of allozyme diversity (17 loci) in 12 populations of the common terrestrial montane orchid Oreorchis patens from the main ranges in Korea and 4 populations of its rare congener O. coreana, which is restricted to the Korean island of Jeju. As expected, O. patens harbored high levels of genetic variation within populations (%P = 62.8, A = 1.96, Ho = 0.211, and He = 0.237). Allele frequency differences among populations were low (FST = 0.075), and the species also displayed a significant correlation between pairwise genetic differentiation and geographical distance. All these results suggest that extant populations were founded by multiple genetically diverse individuals and that most of this initial diversity would have been maintained in the stable mountainous conditions during Quaternary climatic oscillations. In contrast, we were unable to detect any genetic diversity in O. coreana, suggesting that contemporary populations likely originated from a single ancestral source population that had lost all genetic variability. From a long-term conservation genetics perspective, extreme rarity and small population sizes, coupled with its apparent genetic uniformity, place O. coreana at a high risk of extinction. Thus, both in situ and ex situ conservation efforts should be of particular importance for this species.
Bibliographical noteFunding Information:
This work was supported by the Basic Science Program through the National Research Foundation of Korea (KRF) funded by the Ministry of Education, Science and Technology (KRF-2007-521-C00280 to M.G.C.); the Korea Environmental Industry and Technology Institute (KEITI) of Eco-star project (project number 052-08-71 for ‘‘the development of technology for conservation and management of higher plants in Korea’’ to M.G.C. through to B.-Y.S.).
- founder effect
- population history
ASJC Scopus subject areas
- General Medicine