A survey of the genome-wide genetic variation of Hibiscus hamabo (Malvaceae)

Hibiscus hamabo (Malvaceae) is a deciduous shrub mainly found in northeast Asia, including China, Japan, and Korea. Due to its limited distribution on Jejudo Island and at several sites in Jeollanam-do in Korea, H. hamabo has been designated as an endangered species by the Ministry of the Environment and has been the subject of several restoration programs. In this study, we quantified genetic variations using double-digestion restriction-associated DNA sequencing technology in 96 individuals of H. hamabo from 13 distinct populations in Korea. We determined 3,352 genome-wide single nucleotide polymorphism loci after stringent filtering processes and analyzed the level of genetic variation within and among populations as well as the population differentiation and genetic ancestry with var-ious assumptions pertaining to the population origin. Our results indicated weak differenti-ations among populations surveyed in this study but clearly suggested that most of the H. hamabo populations maintain a relatively high level of genetic diversity as evidence of fre-quent genetic exchanges among populations via outcrossing or sequential gene flows. For a more detailed analysis of the origin of Korean H. hamabo and its demographic history, it will be necessary to expand sampling in China and Japan.