• Title/Summary/Keyword: Genetic diversity

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Physical Characteristics and Microsatellite Polymorphisms in Miryang Native Dogs (밀양지방 토종개의 형태학적 특징 및 유전적 다양성 연구)

  • Cho, Byung-Wook;Cho, Gil-Jae
    • Journal of Life Science
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    • v.16 no.4
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    • pp.626-631
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    • 2006
  • This study was carried out to investigate the physical characteristics (height, body lenght, chest depth, head type, ear type, body color, eye type and tail type) and genetic diversity using 15 microsatellite DNA markers (PEZ 1, 5, 8, 10, 11, 12, 13, 15, 16, 17, 20, 21, FHC 2010, FHC 2054 and FHC 2079) in 44 random Miryang native dogs(6 months${\sim}$12 years old). The height, body lenght, and chest depth of Miryang native dogs were 43-55 cm(mean 49.5 cm), 45-60 cm(mean 54.3 cm), and 50-64 cm(mean 57.9 cm), respectively. Miryang native dog was medium sized. The head and eye type were reverse-triangle(100%), triangle (90.9%) and newborn moon(9.1%), respectively. Most of body color had white coat color(93.2%), light pink tongue color(100%), light black anal color(90,9%) and pink claw color(100%). The ear type showed erect ear(100%), and half-curled(56.8%), upward(34.1%), curled(9.1%) in tail type, respectively. Number of alleles observed at a single locus ranged from 2 (PEZ 21 and FHC 2010) to 14 (PEZ 13), with average number of alleles per locus of 6.13. The expected heterozygosities of 15 microsatellite loci were estimated based on gene frequencies. The highest expected heterozygosity, 0.863 was estimated in PEZ 13 locus and the lowest, 0.455 in PEZ 21 and FHC 2010 locus. And the mean expected heterozygosity of 15 microsatellite markers was calculated as 0.635. Polymorphic information content (PIC) values were ranged from 0.348 (PEZ 21 and FHC 2010) to 0.837 (PEZ 13), and the mean PIC value was calculated as 0.570. Of the 15 markers, PEZ 10, PEZ 13, PEZ 17 and FHC 2054 loci have relatively high PIC value (> 0.7) in Miryang native dog. In order to determine the efficieney of parentage control, exclusion probabilities (PE) were calculated for each allele. The highest PE 1 and PE 2 in PEZ 13 locus was caculated to 0.548 and 0.710, respectively. And the total exclusion power in PE 1 and PE 2 was calculated to 0.9895 and 0.9996, respectively. These results can give basic information for perservation and research in Miryang native dog, and phylogenetic relationships of the Korean native dog and Asian dog breeds.

Estimation of Linkage Disequilibrium and Effective Population Size using Whole Genome Single Nucleotide Polymorphisms in Hanwoo (한우에서 전장의 유전체 정보를 활용한 연관불평형 및 유효집단크기 추정에 관한 연구)

  • Cho, Chung-Il;Lee, Joon-Ho;Lee, Deuk-Hwan
    • Journal of Life Science
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    • v.22 no.3
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    • pp.366-372
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    • 2012
  • This study was conducted to estimate the extent of linkage disequilibrium (LD) and effective population size using whole genomic single nucleotide polymorphisms (SNP) genotyped by DNA chip in Hanwoo. Using the blood samples of 35 young bulls born from 2005 to 2008 and their progenies (N=253) in a Hanwoo nucleus population collected from Hanwoo Improvement Center, 51,582 SNPs were genotyped using Bovine SNP50 chips. A total of 40,851 SNPs were used in this study after elimination of SNPs with a missing genotyping rate of over 10 percent and monomorphic SNPs (10,730 SNPs). The total autosomal genome length, measured as the sum of the longest syntenic pairs of SNPs by chromosome, was 2,541.6 Mb (Mega base pairs). The average distances of all adjacent pairs by each BTA ranged from 0.55 to 0.74 cM. Decay of LD showed an exponential trend with physical distance. The means of LD ($r^2$) among syntenic SNP pairs were 0.136 at a range of 0-0.1 Mb in physical distance and 0.06 at a range of 0.1-0.2 Mb. When these results were used for Luo's formula, about 2,000 phenotypic records were found to be required to achieve power > 0.9 to detect 5% QTL in the population of Hanwoo. As a result of estimating effective population size by generation in Hanwoo, the estimated effective population size for the current status was 84 heads and the estimate of effective population size for 50 generations of ancestors was 1,150 heads. The average decreasing rates of effective population size by generation were 9.0% at about five generations and 17.3% at the current generation. The main cause of the rapid decrease in effective population size was considered to be the intensive use of a few prominent sires since the application of artificial insemination technology in Korea. To increase and/or sustain the effective population size, the selection of various proven bulls and mating systems that consider genetic diversity are needed.

Distributional Characteristics and Evaluation of the Population Sustainability, Factors Related to Vulnerability for a Polygonatum stenophyllum Maxim. (층층둥굴레(Polygonatum stenophyllum Maxim.)의 분포특성과 개체군의 위협요인 및 지속가능성 평가)

  • Kim, Young-Chul;Chae, Hyun-Hee;Ahn, Won-Gyeong;Lee, Kyu-Song;Nam, Gi-Heum;Kwak, Myoung-Hai
    • Korean Journal of Environment and Ecology
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    • v.33 no.3
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    • pp.303-320
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    • 2019
  • Plants interact with various biotic and abiotic environmental factors. It requires much information to understand the traits of a plant species. A shortage of information would restrict the assessment, especially in the evaluation of what kind of factors influence a plant species to face extinction. Polygonatum stenophyllum Maxim. is one of the northern plants of which Korea is the southern distribution edge. The Korean Ministry of Environment had designated it to be the endangered species until December 2015. Although it is comparatively widespread, and a large population has recently been reported, it is assessed to be vulnerable due to the low population genetic diversity. This study evaluated the current distribution of Polygonatum stenophyllum Maxim. We investigated the vegetational environment, population structures, phenology, soil environment, and self-incompatibility based on the results. Lastly, we evaluated the current threats observed in the habitats. The habitats tended to be located in the areas where the masses at the edge of the stream accumulated except for those that were located on slopes of some mountainous areas. Most of them showed a stable population structure and had re-established or recruited seedlings. Polygonatum stenophyllum Maxim. had the difference in time when the shoots appeared above the ground depending on the depth of the rhizome located in the underground. In particular, the seedlings and juveniles had their rhizome located shallow in the soil. Visits by pollinator insects and success in pollination were crucial factors for bearing of fruits by Polygonatum stenophyllum Maxim. The threats observed in the habitat of Polygonatum stenophyllum Maxim. included the expansion of cultivated land, construction of new buildings, and construction of river banks and roads. Despite such observed risk factors, it is not likely that there would be rapid population reduction or extinction because of its widespread distribution with the total population of more than 2.7 million individuals and the new populations established by the re-colonization.

A Review of Ecological Niche Theory from the Early 1900s to the Present (생태적 지위(Ecological Niche) 이론에 대한 검토 및 제언)

  • Koo, Kyung Ah;Park, Seon-Uk
    • Korean Journal of Environment and Ecology
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    • v.35 no.4
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    • pp.316-335
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    • 2021
  • This study reviewed the change of theory of ecological niche(concepts and definitions) over time to provide a theoretical basis for habitat-related studies of animals and plants. Accordingly, it analyzed and summarized the major discussion trends of ecological niche worldwide in each period from the 1900s to the present. Countries advanced in ecological studies, such as the EU and the USA, have conducted theoretical and empirical studies on the ecological niche since the early 1990s. The concept of the ecological niche was introduced in the early 1900s, developed in the mid-1900s, and advanced from the mid-1900s to the late 1900s. Since the 2000s, the advanced concept has diversified with new developments in technologies and research methods. The factors suggested by theoretical and empirical studies in defining the ecological niche of a species include 1) population dynamics of the target species, 2) all biotic conditions to sustain a population (food relationship and material flow in the food chain), 3) all non-biotic conditions to sustain a population (physical environmental conditions), 4) all direct and indirect interactions between these environmental factors, and 5) response and adaptation mechanisms that include the migratory ability of the target species or genetic diversity and adaptability to change. Unlike such international advancement, there have not been sufficient theoretical, philosophical, and empirical studies of ecological niche in Korea. The concepts and definitions by Greennell, Elton, and Hutchinson were selectively and partially borrowed for empirical studies without full description. Considering that the theory of ecological niche becomes the foundation for habitat-based species conservation and restoration, it is necessary to seek diversification and advancement of theoretical and empirical research and research methods and technological development. It will provide an important foundation for the academic advancement of ecology and for establishing and implementing policies to preserve and restore ecology and biodiversity effectively and successfully in Korea.

Characterization of Agronomic Traits and Evaluation of Lignan Contents in Asian and African Sesame (Sesamum indicum L.) Germplasms (아시아 및 아프리카 원산 참깨(Sesame indicum L.) 유전자원의 농업형질과 리그난 함량 평가)

  • Sookyeong Lee;Jungsook Sung;Gi-An Lee;Eunae Yoo;So Jeong Hwang;Weilan Li;Tae-Jin Yang
    • Korean Journal of Plant Resources
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    • v.36 no.4
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    • pp.413-434
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    • 2023
  • Sesame (Sesamum indicum L.) is an ancient oilseed crop, which is usually cultivated for its seeds. Sesame breeding aims to achieve high seed yield and quality, along with resistance to biotic or abiotic stresses. It is estimated that sesame is originated from Asia or Africa continent. In this study, we characterized 10 agronomic traits and evaluated lignan contents in 165 sesame germplasm originated from Asia or Africa, to select high-yield or high-lignan content accessions. Sesame germplasm showed diverse phenotypes and highly variable lignan contents (sesamin: 0.5-12.6 mg/g, sesamolin: 0.1-3.5 mg/g, lignan: 1.1-16.1 mg/g). Based on originated continent, there are significant difference in agronomic traits, but no in lignan content. Correlation analysis revealed that yield-related agronomic traits were negatively related with lignan contents. Also, PCA analysis showed that most agronomic traits and lignan contents were principal components explaining diversity of whole sesame germplasm. Sesame germplasm was clustered into three groups based on agronomic traits and lignan contents. Finally, we selected high-yield (IT29416, IT167042, K276848, K276849) and high-lignan candidate accessions (IT169254, IT170031, IT169250, IT154876, IT170034), respectively. These accessions are expected to be valuable resources for breeding of high-yield and high-lignan contents functional cultivars.

A Cross-Sectional Study of Students' Conceptions on Evolution and Characteristics of Concept Formation about It in Terms of the Subjects: Human, Animals and Plants (설명대상에 따른 학생들의 진화 개념과 진화 개념 형성의 특성에 관한 횡단 연구)

  • Ha, Min-Su;Lee, Jun-Ki;Cha, Hee-Young
    • Journal of The Korean Association For Science Education
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    • v.26 no.7
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    • pp.813-825
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    • 2006
  • The purpose of this study was to identify students' conceptions and their conceptualization traits in terms of the explanation of subjects: human, animals, and plants. A questionnaire was specially developed to make sure students' conceptions of evolution, students' explanation patterns with the five evolutionary explanations: creationism, internal will explanation, theological explanations, use and disuse explanation and natural selection after mutation and perceived ideas of evolution in terms of the genetic characters of human, animals and plants. 1,540 elementary, middle and high school students participated in responding to the questions. The data was collected and analyzed cross-sectionally by age. Results showed that students' evolutionary explanations were different among each subject: human, animals and plants. Students had concentrated with more 'theological explanations' than 'internal will explanation' and 'use and disuse explanation' about plant evolution. 'Natural selection after mutation explanation' was less represented in explaining human characters. This result showed that the anthropocentric thoughts had influenced students' evolution conceptions. Accordingly, as student's age, 'theological explanation' and 'internal will explanation' became least used in explaining the theory of creation. 'Use and disuse explanation' attained more representation in their explanation. In addition, the diversity of students' evolutionary explanations was getting less attention as age increases. Among youngers, 'theological explanation', 'internal will explanation' and 'use and disuse explanation' showed an even number of responses. The elders responded with more 'use and disuse explanation'. This result let us infer that 'use and disuse explanation' was strongly adhered to by student cognitive structures. Many students recognized that evolution was a kind of scientific hypothesis with little evidence. They have had a little interest in evolution and conceptualized it through informal educational sources. This study mentions that to teach evolution more effectively, teachers should make 'use and disuse explanation' adhere strongly to students' cognitive structure.

Identifying Distribution Areas and Population Sizes for the Conservation of the Endangered Species Odontobutis obscura (멸종위기종 남방동사리의 보전을 위한 상세 분포 지역 및 개체군 크기 파악)

  • Jeong-Hui Kim;Sang-Hyeon Park;Seung-Ho Baek;Chung-Yeol Baek
    • Korean Journal of Ecology and Environment
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    • v.57 no.2
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    • pp.102-110
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    • 2024
  • This study presents a fine scale distribution of the endangered species, Odontobutis obscura, through field surveys and literature reviews. Using the mark-recapture method, the population size in major habitats was determined. Field surveys conducted on 18 streams in Geoje Island revealed that the O. obscura was only found in the main streams and tributaries of the Sanyang, Gucheon, and Buchun Streams, which are part of the Sanyang Stream watershed. The O. obscura exhibited relative abundances ranging from 0.5% to 35.3% at different locations, with certain spots showing higher relative abundances (18.8% to 35.3%), indicating major habitat areas. A review of six literature studies confirmed the presence of the O. obscura, although there were differences in occurrence status depending on the purpose, scope, and duration of the studies. Combining the results of field and literature surveys, it was found that the O. obscura inhabits the main and tributary streams of the Sanyang, Gucheon, and Buchun Streams, from the upper to lower reaches. Currently, the O. obscura population in the Sanyang Stream watershed maintains a stable habitat, but its limited distribution range suggests potential issues such as genetic diversity deficiency in the long term. The population size of the O. obscura was confirmed at two specific locations, with densities of 0.5 to 1.5 individuals per m2. The average movement distance from the release point was 13.1 m, indicating the limited mobility characteristic of ambush predators. Understanding the distribution and population size of endangered species is the first step towards their conservation and protection. Based on this information, further research could significantly contribute to the conservation of the O. obscura.

Review of the Korean Indigenous Species Investigation Project (2006-2020) by the National Institute of Biological Resources under the Ministry of Environment, Republic of Korea (한반도 자생생물 조사·발굴 연구사업 고찰(2006~2020))

  • Bae, Yeon Jae;Cho, Kijong;Min, Gi-Sik;Kim, Byung-Jik;Hyun, Jin-Oh;Lee, Jin Hwan;Lee, Hyang Burm;Yoon, Jung-Hoon;Hwang, Jeong Mi;Yum, Jin Hwa
    • Korean Journal of Environmental Biology
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    • v.39 no.1
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    • pp.119-135
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    • 2021
  • Korea has stepped up efforts to investigate and catalog its flora and fauna to conserve the biodiversity of the Korean Peninsula and secure biological resources since the ratification of the Convention on Biological Diversity (CBD) in 1992 and the Nagoya Protocol on Access to Genetic Resources and the Fair and Equitable Sharing of Benefits (ABS) in 2010. Thus, after its establishment in 2007, the National Institute of Biological Resources (NIBR) of the Ministry of Environment of Korea initiated a project called the Korean Indigenous Species Investigation Project to investigate indigenous species on the Korean Peninsula. For 15 years since its beginning in 2006, this project has been carried out in five phases, Phase 1 from 2006-2008, Phase 2 from 2009-2011, Phase 3 from 2012-2014, Phase 4 from 2015-2017, and Phase 5 from 2018-2020. Before this project, in 2006, the number of indigenous species surveyed was 29,916. The figure was cumulatively aggregated at the end of each phase as 33,253 species for Phase 1 (2008), 38,011 species for Phase 2 (2011), 42,756 species for Phase 3 (2014), 49,027 species for Phase 4 (2017), and 54,428 species for Phase 5(2020). The number of indigenous species surveyed grew rapidly, showing an approximately 1.8-fold increase as the project progressed. These statistics showed an annual average of 2,320 newly recorded species during the project period. Among the recorded species, a total of 5,242 new species were reported in scientific publications, a great scientific achievement. During this project period, newly recorded species on the Korean Peninsula were identified using the recent taxonomic classifications as follows: 4,440 insect species (including 988 new species), 4,333 invertebrate species except for insects (including 1,492 new species), 98 vertebrate species (fish) (including nine new species), 309 plant species (including 176 vascular plant species, 133 bryophyte species, and 39 new species), 1,916 algae species (including 178 new species), 1,716 fungi and lichen species(including 309 new species), and 4,812 prokaryotic species (including 2,226 new species). The number of collected biological specimens in each phase was aggregated as follows: 247,226 for Phase 1 (2008), 207,827 for Phase 2 (2011), 287,133 for Phase 3 (2014), 244,920 for Phase 4(2017), and 144,333 for Phase 5(2020). A total of 1,131,439 specimens were obtained with an annual average of 75,429. More specifically, 281,054 insect specimens, 194,667 invertebrate specimens (except for insects), 40,100 fish specimens, 378,251 plant specimens, 140,490 algae specimens, 61,695 fungi specimens, and 35,182 prokaryotic specimens were collected. The cumulative number of researchers, which were nearly all professional taxonomists and graduate students majoring in taxonomy across the country, involved in this project was around 5,000, with an annual average of 395. The number of researchers/assistant researchers or mainly graduate students participating in Phase 1 was 597/268; 522/191 in Phase 2; 939/292 in Phase 3; 575/852 in Phase 4; and 601/1,097 in Phase 5. During this project period, 3,488 papers were published in major scientific journals. Of these, 2,320 papers were published in domestic journals and 1,168 papers were published in Science Citation Index(SCI) journals. During the project period, a total of 83.3 billion won (annual average of 5.5 billion won) or approximately US $75 million (annual average of US $5 million) was invested in investigating indigenous species and collecting specimens. This project was a large-scale research study led by the Korean government. It is considered to be a successful example of Korea's compressed development as it attracted almost all of the taxonomists in Korea and made remarkable achievements with a massive budget in a short time. The results from this project led to the National List of Species of Korea, where all species were organized by taxonomic classification. Information regarding the National List of Species of Korea is available to experts, students, and the general public (https://species.nibr.go.kr/index.do). The information, including descriptions, DNA sequences, habitats, distributions, ecological aspects, images, and multimedia, has been digitized, making contributions to scientific advancement in research fields such as phylogenetics and evolution. The species information also serves as a basis for projects aimed at species distribution and biological monitoring such as climate-sensitive biological indicator species. Moreover, the species information helps bio-industries search for useful biological resources. The most meaningful achievement of this project can be in providing support for nurturing young taxonomists like graduate students. This project has continued for the past 15 years and is still ongoing. Efforts to address issues, including species misidentification and invalid synonyms, still have to be made to enhance taxonomic research. Research needs to be conducted to investigate another 50,000 species out of the estimated 100,000 indigenous species on the Korean Peninsula.