• Journal of Ecology and Environment
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• v.45 no.3
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• pp.97-104
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• 2021

Background: Asarum sieboldii Miq., a species of forest understory vegetation, is an herbaceous perennial belonging to the family Aristolochiaceae. The metapopulation of A. sieboldii is distributed sparsely and has a short seed dispersal distance by ants as their seed distributor. It is known that many flowers of A. sieboldii depend on self-fertilization. Because these characteristics can affect negatively in genetic structure, investigating habitat structure and assessment of genetic structure is needed. A total of 27 individuals in a valley were sampled for measuring genetic diversity, genetic distance, and genetic differentiation by RAPDPCR. Results: The habitat areas of A. sieboldii metapopulation were relatively small (3.78~33.60 m²) and population density was very low (five to seven individuals in 20×20 m quadrat). The habitat of A. sieboldii was a very shady (relative light intensity = 0.9%) and mature forest with a high evenness value (J = 0.81~0.99) and a low dominance value (D = 0.19~0.28). The total genetic diversity of A. sieboldii was quite high (h = 0.338, I = 0.506). A total of 33 band loci were observed in five selected primers, and 31 band loci (94%) were polymorphic. However, genetic differentiation along the valley was highly progressed (G_st = 0.548, N_m = 0.412). The average genetic distance between subpopulations was 0.387. The results of AMOVA showed 52.77% of variance occurs among populations, which is evidence of population structuring. Conclusions: It is expected that a small-scale founder effect had occurred, an individual spread far from the original subpopulation formed a new subpopulation. However, geographical distance between individuals would have been far and genetic flow occurred only within each subpopulation because of the low density of population. This made significant genetic distance between the original and new population by distance. Although genetic diversity of A. sieboldii metapopulation is not as low as concerned, the subpopulation of A. sieboldii can disappear by stochastic events due to small subpopulation size and low density of population. To prevent genetic isolation and to enhance the stable population size, conservative efforts such as increasing the size of each subpopulation or the connection between subpopulations are needed.

• Journal of Korean Society of Forest Science
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• v.105 no.4
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• pp.414-421
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• 2016

Fourteen Acer pseudosieboldianum populations in South Korea were used to estimate genetic diversity, genetic differentiation and genetic relationships using seven AFLP primer combinations. The average of effective alleles ($A_e$), the proportion of polymorphic loci (%P) and Shannon's diversity index (I) was 1.4, 82.2% and 0.358, respectively. The expected heterozygosity ($H_e$) under Hardy-Weinberg equilibrium was 0.231 and the expected heterozygosity (Hj) from Bayesian inference was 0.253. The level of genetic diversity was moderate compared to those of Genus Acer and lower than those of other species having similar ecological niche and life history. The inbreeding coefficient within populations ($F_{IS}$) from Bayesian method was 0.712 and it could be influenced by selfing or biparental inbreeding to induce homozygote excess. The level of genetic differentiation was 0.107 from AMOVA (${\Phi}_{ST}$) and 0.110 from Bayesian method (${\Phi}^{II}$). The genetic differentiation was lower than those of other species having similar ecological niche and life history. Ulleungdo population had the lowest level of genetic diversity and was genetically the most distinct population from others in the study. We consider that founder effect and genetic drift might be occurred to reduce genetic diversity and then the geographical isolation might interrupt gene flow to aggravate it.

• Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.49-56
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• 2012

Genetic variation in the Asian shore crab Hemigrapsus sanguineus was determined from partial mitochondrial DNA (mtDNA) sequences of the cytochrome b (Cytb) gene. Samples included 143 crabs from six localities along three coastlines in South Korea. A nucleotide sequence analysis revealed 38 variable sites in a 470-bp sequence, which defined 37 haplotypes. The haplotypes were not associated geographically and had a shallow genealogy. Pairwise $F_{ST}$ tests and a two-dimensional scaling analysis revealed no significant genetic differentiation among most of the populations. The low pairwise comparison values, but significant genetic differentiation of a northeastern population from all other populations, might have been influenced by a restriction in gene flow caused by hydrographic conditions such as ocean boundaries. The high haplotype diversity, low nucleotide diversity, and time since H. sanguineus expansion in Korean coastal waters indicate rapid population growth and a recent, sudden expansion in the Late Pleistocene.

• Plant Resources
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• v.8 no.3
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• pp.293-299
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• 2005

This study used RAPD markers to assume genetic diversity and variation in selected populations of Hovenia dulcis var. koreana. Ratio of polymorphic RAPD markers were 93.4% in selected populations of Hovenia dulcis Thunb., difference of genetic structure among populations and within populations showed 16.45%, 83.55%, respectively in amount of total genetic variation of 4 populations. Total gene diversity($H_T$) that show genetic diversity appeared 0.313 and coefficient of gene differentiation($G_{ST}$) that compare genetic differentiation of populations appeared 0.1645, analysis of AMOVA for variation among populations and within populations was significantly different (P<0.001). Genetic diversity of whole populations showed that 12.44% difference among population and 87.56% difference within populations. As a result, difference within populations was larger than difference among populations in genetic diversity. Nei's genetic distance and cluster analysis appeared that mean genetic distance among populations was 0.076, thus dividing two main groups and geographic relationship did not show in populations.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.1
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• pp.13-19
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• 2009

In the present study, genetic analyses of diversity and differentiation were performed on four breeds of Indian zebu cattle (Bos indicus). In total, 181 animals belonging to Ponwar, Kherigarh, Gangatiri and Kenkatha breeds were genotyped for 20 cattle specific microsatellite markers. Mean number of alleles observed per locus (MNA) varied between 5.75 (Kenkatha) to 6.05 (Kherigarh). The observed and expected heterozygosity for the breeds varied from 0.48 (Gangatiri) to 0.58 (Kherigarh) and 0.65 (Kenkatha) to 0.70 (Kherigarh), respectively. $F_{IS}$ estimates of all the breeds indicated significant deficit of heterozygotes being 28.8%, 25.9%, 17.7% and 17.7% for Gangatiri, Ponwar, Kherigarh and Kenkatha, respectively. The $F_{ST}$ estimates demonstrated that 10.6% was the average genetic differentiation among the breeds. Nei's genetic distance DA and Cavalli- Sforza and Edwards Chord distance ($D_C$) and the phylogenetic tree constructed from these reflected the close genetic relationship of Gangatiri and Kenkatha, whereas Ponwar appears to be more distant.

• Natural Product Sciences
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• v.18 no.3
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• pp.153-157
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• 2012

Obesity, which is characterized by excessive fat accumulation in adipose tissues, occurs by fat absorption by lipase and sequential fat accumulation in adipocyte through adipocyte differentiation. Thus, inhibition of pancreatic lipase activity and adipocyte differentiation would be crucial for the prevention and progression of obesity. In the present study, we attempted to evaluate anti-adipogenic activity of several algae extracts employing preadipocytes cell line, 3T3-L1 as an in vitro assay system. The effects on pancreatic lipase activity in vitro were also evaluated. Total methanolic extracts of Cladophora wrightiana and Costaria costata showed significant inhibitory activity on adipocyte differentiation as assessed by measuring fat accumulation using Oil Red O staining. Related to pancreatic lipase, C. wrightiana and Padina arborescens showed significant inhibition. Further fractionation of C. wrightiana, which showed the most potent activity, suggested that $CHCl_3$ and n-BuOH fraction are responsible for adipocyte differentiation inhibition, whereas n-BuOH and $H_2O$ fraction for pancreatic lipase inhibition. Our study also demonstrated that n-BuOH fraction was effective both in early and middle stage of differentiation whereas $CHCl_3$ fraction was effective only in early stage of differentiation. Taken together, algae might be new candidates in the development of obesity treatment.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.7
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• pp.892-896
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• 2004

A genetic examination using 14 structural loci and 7 microsatellite markers was carried out among random samples of Hu sheep (Hu), Tong sheep (Tong) and Yantse River Delta White goat (YRD); The mean heterozygosity (H), mean polymorphism information contents (PIC) and mean effective numbers of alleles (Ne) calculated based on the data from the above two types of genetic markers were compared. The standard genetic distances among the three populations based on two types of gene frequencies were calculated and compared. The results show that the mean heterozygosity (H), mean polymorphism information contents (PIC) and mean effective numbers of alleles (Ne) based on 7 microsatellite markers are greater than those based on the structural loci. The standard genetic distances based on structural loci among the three populations are: 0.0268-0.2487, the standard genetic distances based on microsatellite markers are: 0.2321-1.2313. The study indicates that structural and microsatellite markers reflect the genetic variation of the three populations consistently: Tong>Hu>YRD. The differentiation between related species or interpopulations can be expressed more effectively by microsatellite markers than structural markers. Oar FCB11, MAF33, Oar AE101, Oar FCB128 and OarFCB304 can be used as representative loci for research on genetic differentiation between sheep and goat.

• Journal of Korean Society of Forest Science
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• v.106 no.4
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• pp.417-423
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• 2017

To provide a ecological restoration strategy considering genetic diversity of Abies koreana in Mt. Jiri, the genetic diversity and the genetic differentiation among sub-populations such as Banyabong, Byeoksoryeong, and Cheonwangbong were investigated. The average number of alleles (A) was 7.8, the average number of effective alleles ($A_e$) was 4.9, observed heterozygosity ($H_o$) was 0.578, and expected heterozygosity ($H_e$) was 0.672, respectively. The level of genetic diversity within sub-populations ($H_e=0.672$) was lower than those of both population ($H_e=0.778$) and species ($H_e=0.759$) level. However, the level of genetic diversity was high compared those of Genus Abies. Genetic differentiation was 0.014 from F-statistics ($F_{ST}$) and was 0.004 from AMOVA analysis (${\Phi}_{ST}$). There was no almost genetic differentiation among sub-populations in Mt. Jiri from bayesian clustering. Therefore, If the seeds are sampled sufficiently by selecting the parameters from three sub-populations, it is possible that we could obtain genetically appropriate materials for ecological restoration.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.447-456
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• 2020

Peanut is an allotetraploid derived from a single recent polyploidization. Polyploidization has been reported to have caused significant loss in genetic diversity during the domestication of cultivated peanuts. Single nucleotide polymorphism (SNP)-based markers such as cleaved amplified polymorphic sequences (CAPS) derived from next-generation sequencing (NGS) have been developed and widely applied for breeding and genetic research in peanuts. This study aimed to identify the genetic diversity and population structure using 30 CAPS markers and 96 peanut accessions from five different origins. High genetic dissimilarities were detected between the accessions from Korea and those from the other three South American origins generally regarded as the origin of peanuts, while the accessions from Brazil and Argentina presented the lowest genetic dissimilarity. Based on the results of the present study, accessions from Korea have unique genetic variation compared to those from other countries, while accessions from the other four origins are closely related. Our study identified the genetic differentiation in 96 peanut accessions from five different origins, and this study also showed the successful application of SNP information derived from re-sequencing based on NGS technology.

• Journal of Ecology and Environment
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• v.43 no.4
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• pp.454-461
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• 2019

Background: Ikonnikov's whiskered bat (Myotis ikonnikovi) is found throughout the Korean Peninsula, as well as in Kazakhstan, Russia, Mongolia, China, and Japan. It is small-sized and primarily inhabits old-growth forests. The decrease and fragmentation of habitats due to increased human activity may influence the genetic structure of bat populations. This study was designed to elucidate the population genetic structure of M. ikonnikovi using mitochondrial genes (cytochrome oxidase I and cytochrome b). Results: The results showed that M. ikonnikovi populations from Korea have high genetic diversity. Although genetic differentiation was not detected for the COI gene, strong genetic differentiation of the Cytb gene between Mt. Jeombong and Mt. Jiri populations was observed. Moreover, the results indicated that the gene flow of the maternal lineage may be limited. Conclusions: This study is the first to identify the genetic population structure of M. ikonnikovi. We suggest that conservation of local populations is important for sustaining the genetic diversity of the bat, and comprehensive studies on factors causing habitat fragmentation are required.