• Title/Summary/Keyword: Structure diversity

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Population genetic structure based on mitochondrial DNA analysis of Ikonnikov's whiskered bat (Myotis ikonnikovi-Chiroptera: Vespertilionidae) from Korea

  • Park, Soyeon;Noh, Pureum;Choi, Yu-Seong;Joo, Sungbae;Jeong, Gilsang;Kim, Sun-Sook
    • 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.

Genetic Diversity and Population Structure of Potentilla freyniana in Korea (한국내 세잎양지꽃의 유전적 다양성과 집단구조)

  • Huh, Man-Kyu
    • Journal of Life Science
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    • v.17 no.7 s.87
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    • pp.877-881
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    • 2007
  • The genetic diversity and population structure of Potentilla freyniana in Korea were determined using genetic variations at 19 allozyme loci. Thirteen of the 19 loci (68.4%) showed detectable polymorphism. Genetic diversity at the population level was high ($H_{EP}$ = 0.270). Total genetic diversity values ($H_T$) varied between 0.190 and 0.584, giving an average overall polymorphic loci of 0.371. The interlocus variation of genetic diversity within populations ($H_S$) was high (0.354). On a per locus basis, the proportion of total genetic variation due to differences among populations ($G_{ST}$) ranged from 0.008 for Fe-2 to 0.310 for Gpi with a mean of 0.065, indicating that about 6.5% of the total allozyme variation was among populations. Wide geographic ranges, perennial herbaceous nature and the persistence of multiple generations are associated with the high level of genetic variation in P. freyniana. The estimate of gene flow based on $G_{ST}$, was high among Korean populations of P. freyniana (Nm =3.57). Although P. freyniana usually propagated by asexually-produced ramets, I could not rule out the possibility that sexual reproduction occurred at a low rate because each ramet may produce terminal flowers.

Genetic diversity and population structure of Atractylodes japonica $K_{OIDZ}.$ in Korea (한국내 삽주의 유전적 다양성과 집단구조)

  • Huh, Man-Kyu;Sung, Jung-Sook;Park, Chun-Geon;Park, Hee-Woon;Seong, Nak-Sul;Moon, Sung-Gi;Huh, Hong-Wook
    • Korean Journal of Medicinal Crop Science
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    • v.10 no.1
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    • pp.5-11
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    • 2002
  • The study of genetic diversity was carried out in Atractylodes japonica $K_{OIDZ}$. Although this species has been regarded as medically important one, there is no report on population structure in Korea. Starch gel electrophoresis was used to investigate the allozyme variation and genetic structure of eight Korean populations of this species. Of the 15 genetic loci surveyed, nine (60.0%) was polymorphic in at least one population. Genetic diversity was high at the species level $(H_{es}=0.144)$, whereas, that of the population level was relatively low $(H_{ep}=0.128)$. Nearly 87% of the total genetic diversity in A. japonica was apportioned within populations. The sexual reproduction, high fecundity, and perennials are proposed as possible factors contributing to high genetic diversity. The indirect estimated of gene flow based on Gst was 1.69.

Genetic diversity and population structure among accessions of Perilla frutescens (L.) Britton in East Asia using new developed microsatellite markers

  • Sa, Kyu Jin;Choi, Ik?Young;Park, Kyong?Cheul;Lee, Ju Kyong
    • Genes and Genomics
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    • v.40 no.12
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    • pp.1319-1329
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    • 2018
  • SSRs were successfully isolated from the Perilla crop in our current study, and used to analyze Perilla accessions from East Asia. Analyses of the clear genetic diversity and relationship for Perilla crop still remain insufficient. In this study, 40 new simple sequence repeat (SSR) primer sets were developed from RNA sequences using transcriptome analysis. These new SSR markers were applied to analyze the diversity, relationships, and population structure among 35 accessions of the two cultivated types of Perilla crop and their weedy types. A total of 220 alleles were identified at all loci, with an average of 5.5 alleles per locus and a range between 2 and 10 alleles per locus. The MAF (major allele frequency) per locus varied from 0.229 to 0.943, with an average of 0.466. The average polymorphic information content (PIC) value was 0.603, ranging from 0.102 to 0.837. The genetic diversity (GD) ranged from 0.108 to 0.854, with an average of 0.654. Based on population structure analysis, all accessions were divided into three groups: Group I, Group II and the admixed group. This study demonstrated the utility of new SSR analysis for the study of genetic diversity and population structure among 35 Perilla accessions. The GD of each locus for accessions of cultivated var. frutescens, weedy var. frutescens, cultivated var. crispa, and weedy var. crispa were 0.415, 0.606, 0.308, and 0.480, respectively. Both weedy accessions exhibited higher GD and PIC values than their cultivated types in East Asia. The new SSR primers of Perilla species reported in this study may provide potential genetic markers for population genetics to enhance our understanding of the genetic diversity, genetic relationship and population structure of the cultivated and weedy types of P. frutescens in East Asia. In addition, new Perilla SSR primers developed from RNA-seq can be used in the future for cultivar identification, conservation of Perilla germplasm resources, genome mapping and tagging of important genes/QTLs for Perilla breeding programs.

Characteristics of Vegetation Structure in Chamaecyparis Obtusa Stands (편백림의 식생구조 특성 분석)

  • Park, Seok-Gon;Kang, Hyun-Mi
    • Korean Journal of Environment and Ecology
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    • v.29 no.6
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    • pp.907-916
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    • 2015
  • The purpose of this study was to identify characteristics of vegetation structure, vegetation succession, and species diversity of artificially planted Chamaecyparis obtusa (CO) stands. The study was carried out by performing vegetation survey for eight CO stands located in Jeollanam-do Province, Korea. Analysis on vegetation classification and ordinations of the stands was conducted using the data from the vegetation survey, and as a result, the stands were classified into five types of communities. Community I showed a considerably lower index of species diversity when compared to other communities because the canopy of the dominant CO was so highly dense that the low-height vegetation was not able to develop or the low-height vegetation almost disappeared due to elimination of weed trees. Meanwhile, the Community II - IV had relatively higher indices of species diversity because various native tree species mixed with the low-height vegetation and competed with each other in the understory and shrub layers to some degree of stability or in their early stage of vegetation development. Community V, lastly, showed higher use intensity as a recreational forest, thus developing simpler vegetation structure on account of artificial intervention. There was positive correlation between photosynthetically active radiation entering the forest floor, number of observed species and index of species diversity. Such characteristics of vegetation structure in CO stands are closely associated with forest management and prescription for planting reforestation, thinning, and brush cutting in the past. There was a slight difference in vegetation structure and species diversity by communities, based on rotation time of the vegetational succession, process of disturbance frequency and disturbance, development, and maturity by planting CO stands. However, when compared to natural forests, the CO stands showed simpler vegetation structure. Because artificial forests are vulnerable in ecosystem service with lower species diversity, a drive for ecological management is needed for such forests to change into healthy ecosystems that can display functions of public benefit.

Performance Evaluation of Space-Time Codes and Channel Estimation in OFDM System for Wireless LANs (무선 LAN을 위한 OFDM 시스템에서 시공간 부호들의 성능 분석 및 채널 추정에 관한 연구)

  • Lee, Sang-Mun;Choi, Hyung-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.8B
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    • pp.760-770
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    • 2002
  • Transmit diversity is an efficient diversity technique to improve performance and spectrum efficiency in wireless communication . Coding scheme designed for the transmit diversity is called space-time coding. In this paper, we propose a training structure to apply the transmit diversity to improve the performance of IEEE802.11a OFDM systems. Based on this training structure, we propose a channel estimation scheme using curve fitting. Also we compare and evaluate the performance of space-time codes. The performance of both diversity using space-time codes and channel estimation scheme is investigated by computer simulation in quasi-static 2-ray rayleigh fading environment.

Genetic Diversity Analysis of Maintaining Lines for Kenyan Sunflower (Helianthus annus L.) Using Allele Specific SSR Markers

  • Mwangi, Esther W.;Lee, Myung-Chul;Sung, Jung Suk;Marzougui, Salem;Bwalya, Ernest C.
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.04a
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    • pp.61-61
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    • 2019
  • In any crop breeding program Selection and use of genetically diverse genotypes to develop cultivars with a broad genetic base is important. Molecular markers play a major role in selecting diverse genotypes. Molecular breeding programs of the crop can be made more efficient by use of molecular markers. The present study was done with an aim of analyzing genetic diversity and the population structure in 24 accessions of sunflower (Helianthus annus L.) from Kenya genetic diversity using 35 EST-SSR and gSSR primers.Out of the 35 markers 3 were not polymorphic as they indicated Polymorphic Information content( PIC) of value 0.00 and so the data analysis was done using 32 markers . The 32 set of markers used produced 29 alleles ranging from 2 to 7with a mean of 3.0 alleles per locus.The average value of polymorphic information contents(PIC) were 0.3 .Genetic diversity analysis using these markers revealed 3 major clusters. This result could be useful for designing strategies to make elite hybrid and inbreeding of crossing block for breeding and future molecular breeding programs to make elite variety.

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Phylogeography of the economic seaweeds Chondrus (Gigartinales, Rhodophyta) in the northwest Pacific based on rbcL and COI-5P genes

  • Yang, Mi Yeon;Kim, Myung Sook
    • ALGAE
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    • v.37 no.2
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    • pp.135-147
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    • 2022
  • The red algal genus Chondrus have long been used as raw materials for carrageenan and dietary fiber in health foods. Despite the importance of genetic information in safeguarding natural seaweed resources, knowledge of the population genetics of Chondrus in the northwest Pacific is limited. In this study, genetic diversity and phylogeographic structure of 45 populations (777 specimens) of Chondrus from Korea, China, and Japan were evaluated based on mitochondrial COI-5P gene sequences, and phylogenetic relationships were confirmed based on plastid rbcL gene sequences. Molecular analyses assigned the specimens in this study to three Chondrus species: C. nipponicus, C. ocellatus, and C. giganteus; phenotype-based species classification was impossible owing to their high morphological plasticity. We found moderate intraspecific genetic diversity and a shallow phylogeographic structure in both for C. nipponicus and C. ocellatus, and low intraspecific genetic diversity in C. giganteus. Each of the three species exhibited high-level intraspecific gene flow among regions based on the most common haplotypes (CN1 for C. nipponicus, CO1 for C. ocellatus, and CG1 for C. giganteus). Our comprehensive genetic information provides insights into the phylogeographic patterns and intraspecific diversity of the economically important Chondrus species. It also highlights the need to conserve existing natural Chondrus resources through continuous monitoring of genetic diversity and phylogeographic pattern.

Analysis of Bird Species Diversity Response to Structural Conditions of Urban Park - Focused on 26 Urban Parks in Cheonan City - (도시공원 구조 및 식생 조건에 따른 조류 종다양성 분석 - 천안시 26개 도시공원을 대상으로 -)

  • Song, Wonkyong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.18 no.3
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    • pp.65-77
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    • 2015
  • The urban park has important functions as a habitat for wildlife as well as open space of rest and community for people. This study was carried out to find what factors of structure and vegetation of urban parks could affect forest bird species diversity in Cheonan city. The study surveyed bird and vegetation species in 26 urban parks, Cheonan city. A correlation analysis and multiple linear regressions were performed to test whether habitat structure and vegetation were the major correlate with species diversity. The results showed the Dujeong park was the most high bird species diversity (H' = 2.13), and the Dujeong-8 park (H' = 2.02) and the Cheongsa park (H' = 1.73) were considerably higher than the other urban parks. The variables that were strongly correlated with bird species diversity were park area, number of subtree species, canopy of shrub, number of shrub species, shape index, canopy of subtree, canopy of tree, and impervious surface ratio. The regression of bird species diversity against the environmental variables showed that 3 variables of park area, canopy of subtree, and canopy of tree were included in the best model. Model variable selection was broadly similar for the 5 optimal models. It means park area and multi-layer vegetation were the most consistent and significant predictor of bird species diversity, because urban parks were isolated by built-up areas. Especially the subtree coverage that provides shelter and food for forest birds was an important variable. Therefore, to make parks circular-shaped and abundant multi-layer vegetation, which could be a buffer to external disturbances and improve the quality of habitats, may be used to enhance species diversity in creation and management of urban parks.