Population Genomics Study and Implications for the Conservation of Zabelia tyaihyonii Based on Genotyping-By-Sequencing

Abstract

Zabelia tyaihyonii (Nakai) Hisauti and H. Hara is a perennial shrub endemic to Republic of Korea that grows naturally in only a very limited region of the dolomite areas of Gangwon-do and Chungcheongbuk-do Provinces in the Republic of Korea. Given its geographical characteristics, it is more vulnerable than more widely distributed species. Despite the need for comprehensive information to support conservation, population genetic information for this species is very scarce. In this study, we analyzed the genetic diversity and population structure of 94 individuals from six populations of Z. tyaihyonii using a genotyping-by-sequencing (GBS) approach to provide important information for proper conservation and management. Our results, based on 3088 single nucleotide polymorphisms (SNPs), showed a mean expected heterozygosity (He) of 0.233, no sign of within-population inbreeding (GIS that was close to or even below zero in all populations), and a high level of genetic differentiation (FST = 0.170). Analysis of molecular variance (AMOVA) indicated that the principal molecular variance existed within populations (84.5%) rather than among populations (17.0%). We suggested that six management units were proposed for conservation considering Bayesian structure analysis and phylogenetic analysis, and given the various current situations faced by Z. tyaihyonii, it is believed that not only the in situ conservation but also the ex situ conservation should be considered.

Approximate Bayesian computation and ecological niche models elucidate the demographic history and current fragmented population distribution of a Korean endemic shrub

“…We also suggest a more in‐depth future analysis of the demographic history of our focal species' five genetic units by sampling more individuals and populations. The challenges to be expected, however, as also for other rare and/or endangered Korean endemics (e.g., Kang et al., 2023; Yun & Oh, 2022), are the little‐known information about the past regional geological and temporal events that may have impacted the present population size and structure of the species (i.e., historical bottlenecks). The effective population sizes of the genetic subdivisions reported here, therefore, should be viewed with caution because possible demographic events that may have occurred after their divergence (e.g., bottleneck and/or expansion) were not taken into account.…”

The genetic structure and demographic history ofZabelia tyaihyonii, endemic to Korean limestone karst forests, based on genome‐wide SNP markers

“…Despite this, the CJ_S6 population does not show unique genetic characteristics and instead forms a clade with geographically more distant populations within CLI, indicating genetic homogeneity. Because a previous study conducted by Kang et al ( 2023 ) had limited coverage of CLII populations, it is challenging to directly compare their findings with our current study. The study demonstrated significant genetic divergence for the CJ_S6 population within the CLI populations.…”

“…There is no evidence that Z. mosanensis has been found anywhere other than in Z. tyaihyonii's habitats. Consequently, Z. mosanensis is regarded as a synonym of Z. tyaihyonii (Sun, 1999), that view is well maintained among Korean researchers (Chae et al, 2023;Kang et al, 2023;Won & Kim, 2007).…”

“…In a given region, the accumulating genetic information for plant species can prove useful in setting conservation priorities (Chung et al, 2017(Chung et al, , 2018 (Nakai) Nakai: Chung et al, 2013;Saussurea chabyoungsanica Im: Jeong et al, 2012]. Also, previous studies of Z. tyaihyonii have sampled a very narrow range, and lacked historical inferences (Jeong et al, 2007;Kang et al, 2023). Therefore, our insight into its effective conservation is very limited.…”

“…Lee: Chung & Chung, 2010 ; Forsythia ovata Nakai and Forsythia saxatilis (Nakai) Nakai: Chung et al, 2013 ; Saussurea chabyoungsanica Im: Jeong et al, 2012 ]. Also, previous studies of Z. tyaihyonii have sampled a very narrow range, and lacked historical inferences (Jeong et al, 2007 ; Kang et al, 2023 ). Therefore, our insight into its effective conservation is very limited.…”