• Journal of Life Science
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• 제17권6호통권86호
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• pp.805-810
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• 2007

Inter simple sequence repeat (ISSR) markers were performed in order to analyse the phylogenetic relationships of eight Hypericum electum populations in Korea. The six primers were produced 37 reproducible ISSR bands. Analysis of ISSR from individual plants of Korean H. erectum resulted in 22 polymorphic bands with 59.5%. Across populations, the mean number of alleles per locus was 1.348 and Shannon's information index was 0.203.Population Mt. Gyeryong had the highest expected genetic diversity (0.175) among all populations. When species were grouped by eight populations, within group diversity was 0.140 (Hs), while among group diversity was 0.472 (G$_{ST}$) on a per locus basis. The estimated gene flow (Nm) for H. erectum was very low (0.561). It is suggested that reproductive isolation by the isolation of geographical distance among H. electum populations and genetic drift may have played roles in shaping the population structure of this species. In phonetic tree, all populations were well separated from each other. Thus, ISSR markers are very effective in classifying natural population levels of genus Hypericum in Korea.

• The Plant Pathology Journal
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• 제37권3호
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• pp.280-290
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• 2021

Population genetic studies of Hemileia vastatrix have been conducted in order to describe the evolutionary dynamics of the pathogen and the disease epidemiology as consequence of changes in disease management and host distribution occurred in Peru after the 2013 epidemic. These analyses were performed by sequencing the internal transcribed spacers of the nuclear ribosomal DNA (rDNA-ITS) of H. vastatrix collected from two coffee growing areas in 2014 and 2018. H. vastatrix population showed high haplotype diversity (Hd = 0.9373 ± 0.0115) with a low nucleotide diversity (π = 0.00322 ± 0.00018). Likewise, AMOVA indicated that fungus population has behaved as a large population without structuring by geographical origin and sampling years (F_ST = 0.00180, P = 0.20053 and F_ST = 0.00241, P = 0.19693, respectively). Additionally, the haplotype network based on intraspecific phylogenetic analysis of H. vastatrix using Peruvian and NCBI sequences revealed that Peruvian ancestral haplotypes, which were maintained in time and space, would correspond to the reported sequences of the races II and XXII. This result suggests that no substantial changes have occurred through time in Peruvian Hemileia vastatrix population.

• Korean Journal of Breeding Science
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• 제41권4호
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• pp.369-376
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• 2009

Cowpea might have been introduced from China to Korea and cultivated for several hundred years but it has never been a staple food crop in Korea. In this study, genetic diversity of 492 Korean cowpea landrace accessions that have passport information was estimated using six SSR markers. The mean of Weir's gene diversity was 0.665 from all accessions investigated in the study. Cowpea gene diversity of six local provinces in Korea was ranged from 0.370 in accessions of Gangwon to 0.680 in Jeonra provinces. Low gene diversity of the cowpea genepool of Gangwon province was probably derived from relatively few introductions. Especially SSR markers VM36 and VM39 seem to be good markers to distinguish the Gangwon accessions from others by occurring at a specific locus with higher than 78% of allele frequency. Except for the Gangwon province with the low genetic diversity, gene diversity of cowpea accessions from other provinces was ranged from 0.600 to 0.680 indicating no big differences among provinces. Distribution pattern of the allele frequencies was similar among the other provinces. This may reveal that Korean farmers might exchange cowpea seeds easily with even their neighbors with geographical barriers. A core collection, 100 landraces, ca. 20% of base collection, was developed at the 70% of a similarity coefficient level using random sampling approaches after stratification of the entire landrace collection based on the phenetic dendrogram. The variability of SSR in the base and core collections of Korean cowpea landrace was compared by calculating Weir's gene diversity. The mean of Weir's gene diversity of the core was 0.707 while that of the base collection was 0.665. The higher diversity index in the core collection indicates that it maintains the initial variability and well represents the base collection. The core collection included one of determinate accession (IT 216155) and two of no branching type accessions (IT 103959 and IT 161024). The core collection could be used to guide more efficient management and utilization of the entire collection. This core collection should be revised periodically as additional accessions are collected and further characterization is conducted.

• Parasites, Hosts and Diseases
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• 제56권2호
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• pp.153-165
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• 2018

Development of an effective vaccine is critically needed for the prevention of malaria. One of the key antigens for malaria vaccines is the apical membrane antigen 1 (AMA-1) of the human malaria parasite Plasmodium falciparum, the surface protein for erythrocyte invasion of the parasite. The gene encoding AMA-1 has been sequenced from populations of P. falciparum worldwide, but the haplotype diversity of the gene in P. falciparum populations in the Greater Mekong Subregion (GMS), including Thailand, remains to be characterized. In the present study, the AMA-1 gene was PCR amplified and sequenced from the genomic DNA of 65 P. falciparum isolates from 5 endemic areas in Thailand. The nearly full-length 1,848 nucleotide sequence of AMA-1 was subjected to molecular analyses, including nucleotide sequence diversity, haplotype diversity and deduced amino acid sequence diversity and neutrality tests. Phylogenetic analysis and pair-wise population differentiation ($F_{st}$ indices) were performed to infer the population structure. The analyses identified 60 single nucleotide polymorphic loci, predominately located in domain I of AMA-1. A total of 31 unique AMA-1 haplotypes were identified, which included 11 novel ones. The phylogenetic tree of the AMA-1 haplotypes revealed multiple clades of AMA-1, each of which contained parasites of multiple geographical origins, consistent with the $F_{st}$ indices indicating genetic homogeneity or gene flow among geographically distinct populations of P. falciparum in Thailand's borders with Myanmar, Laos and Cambodia. In summary, the study revealed novel haplotypes and population structure needed for the further advancement of AMA-1-based malaria vaccines in the GMS.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제39A권8호
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• pp.437-444
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• 2014

In this paper, we propose a path loss model with the multiple antennas and doppler shift for high speed railroad communication. Path loss model is very important in order to design consider diverse characteristic in high-speed train communication. Currently wireless communication systems use the multiple antennas in order to improve the channel capacity or diversity gain. However, until recently, many researches on path loss model only consider geographical environment between the transmitter and the receiver. There is no study about path loss model considering diversity effect and doppler shift. In order to make average residuals considering doppler shift we use tuned free space path loss model which is utilized for measurement results at high speed railroad. The environment of high speed rail is mostly at viaduct and flatland over than 50 percent. And in order to make average residuals considering multiple antenna we use theoretical estimation of diversity gain with MRC scheme. proposed model predict loss of received signal by estimating average residuals between diversity effect and doppler shift.

• Journal of Veterinary Science
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• 제22권4호
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• pp.50.1-50.10
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• 2021

Background: Bovine papillomatosis is a type of proliferative tumor disease of skin and mucosae caused by bovine papillomavirus (BPV). As a transboundary and emerging disease in cattle, it poses a potential threat to the dairy industry. Objectives: The aim of this study is to detect and clarify the genetic diversity of BPV circulating in dairy cows in Xinjiang, China. Methods: 122 papilloma skin lesions from 8 intensive dairy farms located in different regions of Xinjiang, China were detected by polymerase chain reaction. The genetic evolution relationships of various types of BPVs were analyzed by examining this phylogenetic tree. Results: Ten genotypes of BPV (BPV1, BPV2, BPV3, BPV6, BPV7, BPV8, BPV10, BPV11, BPV13, and BPV14) were detected and identified in dairy cows. These were the first reported detections of BPV13 and BPV14 in Xinjiang, Mixed infections were detected, and there were geographical differences in the distribution of the BPV genotypes. Notably, the BPV infection rate among young cattle (< 1-year-old) developed from the same supply of frozen sperm was higher than that of the other young cows naturally raised under the same environmental conditions. Conclusions: Genotyping based on the L1 gene of BPV showed that BPVs circulating in Xinjiang China displayed substantial genetic diversity. This study provided valuable data at the molecular epidemiology level, which is conducive to developing deep insights into the genetic diversity and pathogenic characteristics of BPVs in dairy cows.

• Horticulture, Environment, and Biotechnology : HEB
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• 제59권6호
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• pp.875-888
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• 2018

Tulip (Tulipa L.) is one of the most important ornamental geophytes in the world. Analysis of molecular variability of tulips is of great importance in conservation and parental lines selection in breeding programs. Of the 70 genic microsatellites, 15 highly polymorphic and reproducible markers were used to assess the genetic diversity, structure, and relationships among 280 individuals of 36 wild and cultivated tulip accessions from two countries: Iran and the Netherlands. The mean values of gene diversity and polymorphism information content were 0.69 and 0.66, respectively, which indicated the high discriminatory power of markers. The calculated genetic diversity parameters were found to be the highest in wild T. systola Stapf (Derak region). Bayesian model-based STRU CTU RE analysis detected five gene pools for 36 germplasms which corresponded with morphological observations and traditional classifications. Based on analysis of molecular variance, to conserve wild genetic resources in some geographical locations, sampling should be performed from distant locations to achieve high diversity. The unweighted pair group method with arithmetic mean dendrogram and principal component analysis plot indicated that among wild tulips, T. systola and T. micheliana Hoog exhibited the closest relationships with cultivated tulips. Thus, it can be assumed that wild tulips from Iran and perhaps other Middle East countries played a role in the origin of T. gesneriana, which is likely a tulip species hybrid of unclear origin. In conclusion, due to the high genetic variability of wild tulips, they can be used in tulip breeding programs as a source of useful alleles related to resistance against stresses.

• Journal of the Korean Society of Environmental Restoration Technology
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• 제25권3호
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• pp.29-45
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• 2022

For biodiversity conservation, the importance of beta-diversity which is changes in the composition of species according to environmental changes has become emphasized. However, given the systematic investigation of species distribution and the accumulation of large amounts of data in the Republic of Korea(ROK), research on the spatialization of beta-diversity using them is insufficient. Accordingly, this research investigated the applicability of the Generalized Dissimilarity Modeling(GDM) to ROK, which can predict and map the similarity of compositional turnover (beta-diversity) based on environmental variables. A brief overview of the statistical description on using GDM was presented, and a model was fitted using the flora distribution data(410,621points) from the National Ecosystem Survey and various environmental spatial data including climate, soil, topography, and land cover. Procedures and appropriated spatial units required to improve the explanatory power of the model were presented. As a result, it was found that geographical distance, temperature annual range, summer temperature, winter precipitation, and soil factors affect the dissimilarity of the vegetation community composition. In addition, as a result of predicting the similarity of vegetation composition across the nation, and classifying them into 20 and 100 zones, the similarity was high mainly in the central inland area, and tends to decrease toward the mountainous areas, southern coastal regions, and island including Jeju island, which means the composition of the vegetation community is unique and beta diversity is high. In addition, it was identified that the number of common species between zones decreased as the geographic distance between zones increased. It classified the spatial distribution of plant community composition in a quantitative and objective way, but additional research and verification are needed for practical application. It is expected that research on community-level biodiversity modeling in the ROK will be conducted more actively based on this study.

• Journal of the Korean Geographical Society
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• 제41권4호
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• pp.470-490
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• 2006

The paper critically examines resource mobilization theories, frame theory, and new social movement theories, and proposes studies on the spatiality of the social movements as one potential to mitigate the limitation in these theories. The resource mobilization theories and the frame theory, the strategy-oriented approaches, lack contextual understandings of the origin of social movements. While new social movement theories provide macro-scale analysis and the structural explanations of the origins of social movements, they have covered limited geographical areas. The spatiality of social movements promotes deep understandings of local differences, and contexts in and through which grievances are constructed and collective actions are organized. Physical structures and symbolic representations of places are often created and utilized as social movement strategies. The spatiality of social movements can be a useful conceptual tool to explain the diversity and the dynamics of social movements.

• Animal Systematics, Evolution and Diversity
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• 제7권1호
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• pp.127-150
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• 1991

The stony corals known from Korean waters are 24 species , 15 genera, 7 families in 5 suborders, of which 7 species are newly recorded to the Korean scleractinian fauna ; Montipora trabeculata, Oulangia stokesiana miltoni, Goniocorella dumosa, Dendrophyllia arbuscula, D.boschmai cyathohelioides, D. micranthus, and Rhizopsammia minuta mutsuensis. They were collected from 35 localities of southern Korea from 1969 to 1986. For the geographical analysis, the coastal waters of Koarea are divided into four regions ; the Yellow Sea, the Korea Strait, the Cheju Island area and the East Sea (Sea of Japan) . These are based on the species diversity , the geographical distribution form, and the community coefficient, Korean scleractinians consists of 8 temperate zone forms(33.3%, Te) and 16 tropical forms(66.7%, Tr) . Concerning the distribution in each region, 3 spp. (2 Te, 1 Tr) occur in the Yellow Sea, 9 Spp. (5 Te, 4 Tr) in the Korea Strait, 16 spp.(4 Te, 12 Tr) in the Cheju Island area and 5 spp. (2 Te, 3 Tr) in the East Sea. The communicty coefficient between the Korea strait and the East Sea is the highest (0.596), and that between the Yellow Sea and the Cheju Island area is the lowest(0).