draft genome of the endangered shrub Abeliophyllum distichum

Natural monument habitats play an important role in biodiversity conservation by providing species refuge and allowing species migration, in addition to the pride they bring to a local community or nation. Despite their status, these protected areas are often confined to cultural and fragmented landscapes due to anthropogenic land-use demands. In this population genomic study, we surveyed 11 populations of the endemic shrub Abeliophyllum distichum Nakai (Oleaceae), including five natural monument habitats, covering its range-wide distribution in South Korea. Using more than 2,000 SNPs as markers, our results showed a mean genetic diversity ( He ) of 0.319, with populations in the central distribution showing relatively higher He than those at the periphery. There was no significant heterozygote deficiency and inbreeding among studied populations overall, except for a single natural monument population (GS-NM147). Population structure and differentiation was moderate to high ( F ST = 0.196), while recent gene flow between populations appeared weak, which can be attributed to the fragmented distribution and the outcrossing mating system of the heterostylous plant. Based on these findings, we provide suggestions for the population conservation and management of this endangered, monotypic taxon.