Genetic diversity in three species of Forsythia (Oleaceae) endemic to Korea: Implications for population history, taxonomy, and conservation

► Genetic variation within populations of Forsythia ovata and F. saxatilis is high. ► Low to moderate among-population differentiation has been found in the two Forsythia species. ► These results suggest that limestone ranges in Korea would have acted as refugia. ► Allozyme data indicates that F. ovata and F. saxatilis are conspecific. ► Both in situ and ex situ conservation strategies for Forsythia ovata are needed.