Genetic diversity of the thalictrum coreanum LĚv, an endangered plant species in south Korea, and of the congener thalictrum ichangense Lecoyer: Implications for conservation

Abstract

Thalictrum coreanum (Ranunculaceae), an endangered herb in South Korea, and widespread T. ichangense are congeneric species with similar morphologies and life forms. Currently, there is a debate about the identification and distribution of these two species. We carried out a comparative analysis of the genetic variability of these two species using random amplified polymorphic DNA (RAPD) markers. Genetic diversity at species level was high, but lower at the population level. Analysis of molecular variance (AMOVA) appeared to moderate genetic differentiation among the species. In the total variance of T. coreanum, 54.53% was attributable to among populations and 45.66% to within populations. On the other hand, 35.24% of the total variance was due to among populations, while 64.76% was due to the within populations of T. ichangense. Our results for T. coreanum and T. ichangense showed a high commonality at the genetic level. T. coreanum appeared to have a genetic diversity at a similar level to T. ichangense. In the AMOVA and Principle Coordinate Analysis (PCoA), however, T. coreanum cleary distinguished with T. ichangense. To secure and preserve an endangered species, systematizing species information should be prioritized, according to the accurate criteria. Therefore, the use of a molecular marker such as RAPD could provide hints, diminishing the uncertainty of the distribution area and the identification of these two congeneric species.