Population genetic structure of wild Angelica acutiloba, A. acutiloba var. iwatensis, and their hybrids by atpF-atpA intergenic spacer in chloroplast DNA and genome-wide SNP analysis using MIG-seq.

Sampling surveys of Angelica acutiloba and A. acutiloba var. iwatensis, which are medicinal plants endemic to Japan, were conducted in the Chubu region in the central area of the main island of Japan. A. acutiloba grows in riverbeds in mountainous areas, while A. acutiloba. var. iwatensis grows on slopes near mountain ridges at 1000 m above sea level or on constantly collapsing rocky slopes and bare fields on developed land along asphalt roads in valleys of mountainous areas. Specimens of two wild Angelica species collected in this region were examined for maternal lineage by DNA polymorphism analysis of the atpF-atpA region for chloroplast DNA using direct sequencing and genomic component analysis by genome-wide SNP using MIG-seq. In this study area, while all A. acutiloba populations were monophyletic in both maternal and ancestral lineages, A. acutiloba var. iwatensis were genetically heterogeneous due to being composed of three maternal and three ancestral lineages to various degrees. In addition, a natural hybrid population with maternal lineage presumed to be A. acutiloba and paternal lineage A. acutiloba var. iwatensis was also found. In the present study, we report that the combined method of atpF-atpA and MIG-seq analyses is a useful tool for determining the population genetic structure of two wild Angelica species and for identifying hybrids.