본 연구에서는 유럽 양송이 자원들을 SSR marker를 통 해 유전적 다양성과 집단 구조, 유전적 분화에 대하여 분석하였다. 본 연구에서 유럽의 양송이 자원들은 유전적 거리기반의 4개의 그룹으로 나뉘었고 집단구조 분석을 통하여 2개의 subpopulation으로 이루어져 있었다. 본 연구에서 사용한 SSR 마커로 유럽의 양송이 자원들은 지리적 그리고 갓색으로 구분되지 않았다. 유전적 다양성은 유전적 거리기반의 그룹에서는 Group 4, 집단구조 분석을 통한 subpopulation에서는 Pop. 2의 다양성이 높았다. 그리고 양송이 자원들은 유전적 분화가 매우 낮았다. 본 연구의 결과는 차후 양송이의 육종 등에 이용 할 수 있을 것이다.

본 연구에서는 한국에서 개발한 23개의 양송이 품종과 42개의 도입품종의 유전적 다양성과 집단 구조를 SSR 마커를 이용하여 분석하였다. 양송이 품종의 NA는 약 13, HO는 약 0.59, HE는 약 0.74, PIC값은 약 0.71 이었다. 양송이 품종은 군집분석에 의하여 3개의 Group으로 구분되 었고 다양한 국가의 품종으로 구성된 Group2의 다양성이 높았으며, 구조분석에 의하여 2개의 subpopulation으로 구분되었고, 품종의 수가 많은 Pop2의 다양성이 높았다. 한국의 양송이 품종들은 주로 Group 3에 분포하고, subpopulation 간 분포에는 큰 차이를 보이지 않았다. 본 연구의 결과는 양송이의 육종소재의 개발, 다양성 확보 등과 같은 품종의 개발과정에 이용될 수 있을 것이다.

북방종개(Iksookimia pacifica)의 유전적 다양성과 구조적 특징을 밝히기 위해 동해 독립하천들에 서식하는 10개의 집단들을 대상으로 핵유전자와 미토콘드리아 유전자에 기반한 집단유전학적 분석을 실시하였다. 일부 예외적인 경우를 제외하고, 미토콘드리아와 핵유전자 모두 통계적으로 유의미한 집단 간 유전적 분화가 관찰되었다. 핵유전자들의 DNA 서열자료에서 추출한 유전자형 자료를 Bayesian 방법으로 분석한 결과 북방종개는 천진천과 양양남대천을 기준으로 북쪽과 남쪽의 두 개의 그룹으로 나뉘는 구조를 보였다. 현재 동해 하천들이 지리적으로 단절되어 온 독립 수계라는 것을 감안했을 때, 남북으로 구별되는 집단유전적 구조는 북방종개가 한반도에 정착했던 초기 조상 집단이 남북으로 갈라지는 지리적인 분리 사건과 관련되었을 것으로 해석되며, 이러한 초기 조상집단의 지리적 분리 이후, 두 조상 그룹들은 남북의 지리적인 범위 내에서 하천 별 고립에 따른 추가적인 분화 과정을 거쳤을 것으로 추정된다. 주목할 점으론, 자산천 집단의 많은 개체들이 지리적 거리가 먼 양양남대천 및 강릉남대천 집단과 하나의 유전적 cluster를 형성하고 있는 것이다. 이와 함께 미토콘드리아 유전자의 경우 몇몇 이웃하는 집단들 사이에 현저히 낮은 유전적 분화도 그리고 일부 집단들에서 매우 낮은 유전적 다양성이 관찰되었다. 본 집단유전학적 결과는 향후 북방종개의 보존 및 관리를 위한 기초자료로 제시될 것이다.

The Japanese oak silkmoth, Antheraea yamamai Guérin-Méneville 1861 (Lepidoptera: Saturniidae), is one of the important natural resources possessing industrial value for silk fiber production. In this study, ten microsatellite markers and two mitochondrial DNA (mtDNA) gene sequences (COI and ND4) were used to investigate the genetic variation and geographic structure of A. yamamai populations in South Korea. Two mtDNA gene sequences revealed very low total genetic variation and resultant low geographic variation, validating to use further variable molecular markers. Population-based FIS, FST, RST, and global Mantel test consistently support that A. yamamai populations are overall well interconnected with a relatively high gene flow. Nevertheless, STRUCTURE analysis using microsatellite data and mtDNA sequences coincidently indicate the presence of two genetic pools in many populations.

Brachymystax lenok tsinlingensis (family Salmonidae), cold freshwater fish, is endemic to Asia. This species is currently distributed throughout Russia, Mongolia, China and the Korean Peninsula. B. lenok tsinlingensis in South Korea was severely affected by anthropogenic activities such as habitat destruction, agricultural run-off and water pollution, and hence this fish has recently been dramatically decreased in its population sizes and become now critically endangered. To recover the number of individuals of B. lenok tsinlingensis, stocking or translocation programs have been conducted continuously by local governments since 1970s. However, these programs made little effort to clarify populations that may have originated from stocked, translocated or introduced fish. An understanding of genetic characteristics of endangered populations is critical to develop effective conservation and restoration plans especially because genetic diversity ensues their future fate. Therefore, we assessed the “conservation status” of this species by estimating the level of genetic diversity and genetic structure among ten geographic populations including restored populations via reinforcement and supplementation. Also, we aimed to trace the genetic origins of the newly translocated population (Chiak) through a restoration practice program. Moreover, we inferred the phylogenetic relationships among Korean lenok populations as well as across the Northeast Asia. Two hundred eighteen individuals of B. lenok tsinlingensis were sampled from ten localities (Yanggu, Injae, Seorak, Bangtae and Hongcheon: North Han River basin; Pyeongchang, Chiak and Jeongseon: South Han River basin; Taebaek and Bonghwa: Nakdong River basin in South Korea). Based on mitochondrial DNA (mtDNA) control region and eight nuclear microsatellite loci, we found extremely low levels of within-population genetic diversity, which suggests small effective population sizes (Ne) within populations. For mtDNA control region, each population housed one, or at most, two haplotypes that are restricted to the respective localities, meaning that these ‘genetically unique’ lineages will be lost permanently if the local populations undergo extinction. The overall values of haplotype diversity (h) and nucleotide diversity (π) for the entire Korean population were 0.703 ± 0.024 and 0.021 ± 0.010, respectively. In the case of microsatellites, average number of alleles across the eight loci for the entire population was 9.1 and allelic richness (AR) per population ranged from 2.375 to 4.144 (mean = 3.104). The values of observed heterozygosity (HO) and expected heterozygosity (HE) were similar to each other [HO: 0.400 ~ 0.590 (mean = 0.518); HE: 0.407 ~ 0.608 (mean = 0.504)]. The inbreeding coefficient (FIS) values were generally low, ranging from 0.048 to 0.279. Consequently, the majority of the populations (except Yanggu and Pyeongchang) were not significantly deviated from Hardy-Weinberg equilibrium (HWE), suggesting random mating at these loci tested. In addition, we found that Korean lenok populations were significantly genetically isolated from each other, with private mtDNA haplotypes and microsatellite alleles, indicating limited gene flow among populations, strong effects of genetic drift due to small Ne, or a combination of both. The Mantel test of microsatellites revealed a significant correlation (r = 0.414, P = 0.04) between genetic and geographic distances for pairwise comparisons among the ten populations, while that of mtDNA showed a lack of correlation. Given the shared identical mtDNA haplotype and similar microsatellite allelic distributions between Chiak and Hongcheon populations, we suggest that the restored (introduced) Chiak population would be inferred to be genetically originated from Hongcheon population. Phylogenetic relationships among Northeast Asian populations showed that South Korean lineages have more recently diverged from China (Yellow River), than between North Korea and Russia. Although the phylogenetic relationship would be expected to be associated with geography, South-North Korea and China populations with a similar latitude was more phylogenetically closely related. These findings may suggest a possible scenario for the historical movements of B. lenok tsinlingensis in Northeast Asia during Last Glacial Maximum (LGM). It would be supported by the line of evidence that most lenok populations migrated to southward from Northern Asia such as Russia and Mongolia during LGM because the Korean Peninsula was landlocked as inland epoch and functioned as a southern shelter with Yellow River. For this reason, the Korean Peninsula is suggested to be an important geographical region for better understanding phylogenetic relationships and evolutionary histories of B. lenok tsinlingensis across the Northeast Asia. Despite large efforts made to develop several restoration programs in South Korea for B. lenok tsinlingensis, it is still unknown whether these past restoration efforts were successful or fruitless, mainly because of little attention paid to post-restoration monitoring research. Hence, there was a lack of their published official records. In the future, conservation and restoration projects of the Korean lenok populations should consider the genetic data for a better understanding of their ecological and evolutionary trajectories. And finally, we hope that our findings here can help inform on the future effective conservation and restoration plans for B. lenok tsinlingensis populatio ns in South Korea.

Seagrasses, sea flowering plants, comprise approximately 60 species globally and are often called ‘ecosystem engineers’ because they create their own habitats by modifying the surrounding environments, which provide coastal zones with a number of crucial ecosystem services. Zostera marina (the common name ‘eelgrass’) is one of the seagrass beds-forming species distributed widely in northern hemisphere including the Korean coast, which plays a pivotal role in ecosystem as a primary producer and a nursery habitat or refuge for other marine organisms. However, due to global climate change and anthropogenic activities such as reclamation and dredging, there has recently been a drastic decline in population sizes of Z. marina in Korea. In order to develop effective conservation and restoration management programs of Z. marina populations, it would be helpful to consider all biological aspects of this species such as genetic characteristics as well as ecological and physiological features. This study first provides information on genetic diversity and genetic structure of Jeju Island and Namhae populations of Z. marina, which will contribute to the establishment of appropriate conservation and restoration management plans for future persistence of this species. Using six microsatellite markers, we investigated the level of genetic diversity and genetic structure among 10 geographic populations of Z. marina inhabiting Jeju Island (Hamdeok, Tokki-seom, Sungsan, Woljeong, Ojo) and Namhae (Gamak bay, Jindong bay, Nampo, Anggang bay, Geoje) on the southern coast of Korea. The level of genetic diversity within Jeju populations (mean allelic richness [AR]: 1.57 ~ 3.09) was found to be significantly lower than Namhae populations (AR: 3.09 ~ 4.29) (Mann-Whitney U-test, P < 0.05). These findings suggest that effective population sizes (Ne) of Jeju populations are generally smaller than those of Namehae populations. Within Jeju Island, Hamdeok population had the smallest population size (coverage: 138 m2) and the lowest genetic diversity (AR: 1.57), while Ojo population had the largest population size (coverage: 275,736 m2) and the greatest level of genetic diversity (AR: 3.09). Hamdeok population showed evidence of genetic bottleneck. These results again suggest that Ne of Jeju populations is generally low (except Ojo population). Among Jeju populations, all pair-wise comparisons of FST values (i.e., degree of genetic differentiation) were highly significant (FST = 0.0612 ~ 0.7168, P < 0.001) despite Jeju populations that were geographically closely located, indicating that these local populations are genetically divergent, probably due to a lack of gene flow among the populations. The observed strong population structure was substantiated by evidence that five genetic clusters are most likely, based on population assignment test (STRUCTURE). The Mantel test showed a positive relationship between genetic distance (FST) and geographic distance (km) across all the populations sampled (R2 = 0.4118, P < 0.05), suggesting that our data follow Isolation By Distance (IBD) model. Woljeong population revealed the highest level of FST values compared to other populations within Jeju Island in IBD. STRUCTURE and factorial correspondence analysis (FCA) further showed that some Woljeong individuals included genotypes of Namhae populations. Population size of Woljeong (coverage: 310m2) was approximately 50 % smaller than that of Sungsan (coverage: 841m2); however, extent of its genetic diversity (AR: 2.39) was even higher than that of Sungsan population (AR: 1.77). We speculated that Woljeong population underwent a transplantation from Namhae populations with relatively higher level of genetic diversity. FST values within Namhae populations were relatively lower (compared to within Jeju Island) despite the populations that were geographically more distant. It means that level of gene flow is higher among Namhae populations than among Jeju populations. Z. marina is known to have different life histories by water depth. In subtidal zone (deep water depth) populations predominantly undertake sexual reproduction through seeds such as annual life history, whereas those of intertidal zone (shallow water depth) undertake both sexual and asexual reproductions through horizontal rhizomes i.e., perennial life history. STRUCTURE analysis showed no clear differences between shallow and deep populations at Namhae, but some FST values were statistically significantly different despite their low values. For Geoje population sampled in 2005, intertidal and subtidal populations were not significantly different (FST = 0.0045, P = 0.033), but these populations sampled in 2015 showed a significant difference (FST = 0.0328, P < 0.001). It means that genetic structure of Geoje has been changed over the 10 year period between shallow and deep populations. Overall, the Jeju and Namehae populations analyzed in the current study have relatively low levels of genetic diversity and distinct genetic compositions, which warns the message that this ecologically important species should be conserved separately in the local populations and with high priority. We propose that future conservation and restoration plans for seagrasses should consider genetic characteristics particularly because a close relationship between genetic diversity and ecological performance in marine species has been well documented.

Sesame is queen of oil seed crops and widely cultivated in Asia and Africa. The aim of this study was to develop a mini sub core set representing the diverse germplasm of sesame and to assess the genetic diversity, population structure and phylogenetic relationship of the resulted sub core set to be used in whole genome resequencing platform. One hundred twelve accessions out of 277 accessions were selected by the PowerCore program. A total of 155 alleles were captured from the 158 alleles detected in the primary core population, and rare alleles and specific alleles were also maintained in the sub core set accessions representing almost 100% of the primary core population. Among the sub core set accessions, four sub populations were observed with some admixture accessions. Although the genetic diversity of Pop-1 which includes most accessions from Korea is relatively lower than that of other three sub populations, it can maintain maximum number of accessions in the sub core set with the same percentage as in the primary core set probably because of the specific features of these accessions. Based on this framework of genetically defined populations, the effective use and conservation management of Sesamum indicum for crop improvement might be possible.