Phylogeography of the temperate grassland plant Tephroseris kirilowii (Asteraceae) inferred from multiplexed inter-simple sequence repeat genotyping by sequencing (MIG-seq) data

A group of temperate grassland plant species termed the Mansen elements occurs in Japan and is widely distributed in the grasslands of continental East Asia. It has been hypothesized that these species are continental grassland relicts in Japan that stretch back to a colder age, but their migration history has not been elucidated. To assess the migration history of the Mansen elements, we performed phylogeographic analyses of Tephroseris kirilowii, a member of this group, using single-nucleotide polymorphisms (SNPs) obtained from multiplexed inter-simple sequence repeat genotyping by sequencing (MIG-seq). It was estimated that the Japanese populations of T. kirilowii were divided from those of continental East Asia at 25.2 thousand years ago (ka) with 95% highest probability density interval (HPD) of 15.3-40.0 ka and that Japanese clades first diverged at 20.2 ka with 95% HPD of 10.4-30.1 ka. As the climatically suitable range during the last glacial maximum (LGM) estimated using ecological niche modeling (ENM) was limited in Japan and there was a slight genetic differentiation among Japanese populations, a post-glacial expansion of T. kirilowii in the Japanese Archipelago was indicated.

Automated summary

A group of temperate grassland plant species, known as the Mansen elements, are found in Japan and continental East Asia. Researchers hypothesized that these species are remnants of continental grasslands in Japan from a colder age, but their migration history remained unclear. To investigate the migration history, the phylogeographic analysis of Tephroseris kirilowii, a member of the group, was conducted using single-nucleotide polymorphisms (SNPs). The results showed that the Japanese populations of T. kirilowii diverged from continental East Asia around 25.2 thousand years ago, with the first divergence within Japan occurring around 20.2 thousand years ago. The study suggested a post-glacial expansion of T. kirilowii in Japan based on limited suitable climate during the last glacial maximum and slight genetic differentiation among Japanese populations.