• Title/Summary/Keyword: Population variation

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Genetic Diversity and Population Structure of Glehnia littoralis (Umbelliferae) in Korea

  • Huh Man Kyu;Choi Joo Soo;Huh Hong Wook;Choi Yung Hyun;Choi Byung Tae
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.6
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    • pp.1519-1523
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    • 2003
  • Glehnia littoralis Fr. Schmidt (Umbelliferae) is a short-lived herbaceous species that are mostly distributed throughout East Asia. Although G. littoralis has been regarded as ecologically 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 Korean populations of this species. A high level of genetic variation was found in G. littoral is populations. Nine enzymes revealed 18 loci, of which 12 were polymorphic (66.7%). Genetic diversity at the species and population levels were 0.159 and 0.129, respectively. The sexual and asexual reproduction, high fecundity, and colonization process are proposed as possible factors contributing to genetic diversity. An indirect estimate of the number of migrants per generation (Nm = 1.45) indicated that gene flow was not extensive among Korean populations of this species. It is suggested that the ability of vegetation and artificial selection may have played roles in shaping the population structure of this species. we recommend that a desirable conservation population should be included at least 30 plants per population and especially those with high variation.

Variation in Demography of Taraxacum officinale Seeds Harvested from Different Seasons

  • Yang, Hyo-Sik;Oh, Man-Ho
    • The Korean Journal of Ecology
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    • v.26 no.2
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    • pp.82-86
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    • 2003
  • We investigated the variation in adaptation to growth for four ecotypically-differentiated population of Taraxacum officinale found naturally in temporal environmental heterogeneity. Seeds collected from the four seasons were germinated in incubators and were grown for four months in greenhouse to test genetic variation among biotypes. Biotypes, segregated by seeds collected seasonally, were the part of natural population in Mokpo, South Korea. Each biotype was different in total dry weight of seeds, biomass, and leaf area, confirming previous finding. Differences between biotypes grown under a common environment indicated a genetic basis to their distinct demographic rates. Therefore, biotypes with similar annual rates of growth and contrasting seasonal rates should persist in the population. This differential response suggests that temporal variation in environment may be responsible, in part, for the maintenance of genetic variation within populations.

Genetic Variation and Population Structure of Crepidiastrum lanceolatum (Compositae)

  • Huh, Man-Kyu;Choi, Joo-Soo
    • Journal of Life Science
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    • v.12 no.1
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    • pp.9-13
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    • 2002
  • Crepidiastrum lanceolatum ($H_{OUTT}$) $N_{AKAI}$ (Compositae) is distributed in East Asia including Korea. Genetic diversity and population structure of six C. lanceolatum populations in Korea and two populations in Japan were determined using genetic variation at 19 allozyme loci. The percent of polymorphic loci within the enzymes was 42.1%. Genetic diversity at the species level and at the population level was low (Hes : 0.077; Hep : 0.068, respectively), where-as the extent of the population divergence was relatively low ($G_{ST}$ : 0.093). One of the most striking features of this study was the more significant difference within populations than among populations. An indirect estimate of the number of migrants per generation (Nm : 2.44) indicated that gene flow was moderate among eight populations of the species. In addition, analysis of fixation indices revealed a slight heterozygosity deficiency in some populations and at some loci. Narrow geographic ranges, short-lived perennial herbaceous, and small population sizes are mainly associated with the low level of genetic variation.n.

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Seasonal Variation in Catchability of Penaeid Prawns in the Night-time Prawn Fishery in Albatross Bay, Gulf of Carpentaria, Australia

  • Park Young Cheol;Warburton Kevin;Die David J.
    • Fisheries and Aquatic Sciences
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    • v.5 no.2
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    • pp.114-121
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    • 2002
  • A correction index of catchability (CIC) was derived using a 6 year research data set to examine the seasonal variation in catchability for the night time prawn fishery in Albatross Bay. CIC reflects the composite effect of the monthly variation in size selectivity, emergence­burying behaviour and population density variation of prawn populations. The values of CIC for four dominant species, Metapenaeus endeavouri, M. ensis, Penaeus semisulcatus and P. esculentus, were examined. The value of CIC for M. endeavouri varied substantially and was the highest in August. The values of CIC for M. ensis were high during November to March and the seasonality was weaker than that for M. endeavouri. The monthly variation in CIC for P. semisulcatus reflected the seasonal variation in population density, being high during November to February. These results suggest that the catch ability of P. esculentus is steady throughout the year but it varies greatly on a seasonal basis for M. endeavouri.

Population Genetic Structure of Carassius auratus (Pisces: Cypriniformes) in South Korea Inferred from AFLP Markers: Discordance with Mitochondrial Genetic Structure

  • Jung, Jongwoo
    • Animal Systematics, Evolution and Diversity
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    • v.29 no.1
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    • pp.18-22
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    • 2013
  • A recent study on the mitochondrial genetic variation of the Carassius auratus population in South Korea suggested that there are 3 distinct mitochondrial lineages in the country, and that they are geographically separated between westward rivers and southward rivers, respectively. In this study, the population genetic structure of amplified fragment length polymorphism (AFLP) of Carassius auratus was investigated. The results of analysis of molecular variance (AMOVA) supported the geographic distinction between westward and southward river populations, but only 3.66% of total genetic variance lies among these populations. The panmicticity of the AFLP genetic variation is backed up by the results of the neighbor-joining dendrogram drawn from a linearized pairwise $F_{ST}$ matrix and Bayesian clustering analysis. The discordance of genetic structure between mitochondrial and AFLP genetic variation may come from difference in effective population size between these markers and/or gene flow between westward and southward river populations through river capture events.

Genetic Studies on the Lady-Beetle , Harmonia axyridis Pallace, Population in Korea 3. Variation of elytral pattern and elytral edge in southern population (한국산 무당벌레(harmonia axyridis)의 유전학적 연구 3. 남부집단의 초혈반문 및 초혈벽의 변이에 관하여)

  • 강영선;김창효
    • The Korean Journal of Zoology
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    • v.8 no.1
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    • pp.8-10
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    • 1965
  • 1. We have observed the frequency , geographi variation and microgeographic variation of the elytral pattern types and the elytral edge of the population of Lady-beetle, Harmonia axyridis PALLACE, collected in Jinju and other 6 localitites in South Korea. 2. the number of specimen collected were 6,625 in which Succinea was 90.32% : Axyridis ; 0.74% : Spectabilis , 3.82% ; and Conspicua 5.07%. 3. We have found that 92.26% of all specimens have elytral edge. 4. There were some differences in the compositional of the elytral pattern types and elytral edge to the population among the Western seaside , inland and southern seaside of South Korea , whereas as great difference was in the compositional proportion tot he population of Spectabilis between the western and southern seaside . There was also a gret difference of the elytral edge between the inland and southern seaside. 5. A micro-geographic variation was observed in Jinju , located on southern area of South Korea. In the samples collected from the pine trees at Jinju area the Succinea occupied 73.25%, and 69.61 % were found to be provided with elytral edge, while in the general population 92.46% of specimen were Succinea and 98.35% were found to have elytral edge.

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The Variation in Foliar Characteristics of Natural Population of Camellia japonica L. (동백나무 천연집단(天然集團)의 엽형질(葉形質) 변이(變異))

  • Kim, Yong Shik
    • Journal of Korean Society of Forest Science
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    • v.69 no.1
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    • pp.69-75
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    • 1985
  • These studies were carried out to know the variation of foliar characteristics of Camellia japonica distributed in Korea. The results are summarized as follows; 1) The values such as leaf length, leaf width, and leaf area were the most highest in Chukdo population, while the lowest in Chejudo population. 2) The values of Wando population showed the most highest in leaf serration characters, while the values of Kochang population the lowest. 3) In the number of cort warts, the values of Chundo population showed the most highest, while Dodcong population the lowest.

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Genetic Relationships among Australian and Mongolian Fleece-bearing Goats

  • Bolormaa, S.;Ruvinsky, A.;Walkden-Brown, S.;van der Werf, J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.11
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    • pp.1535-1543
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    • 2008
  • Microsatellites (MS) are useful for quantifying genetic variation within and between populations and for describing the evolutionary relationships of closely related populations. The main objectives of this work were to estimate genetic parameters, measure genetic distances and reconstruct phylogenetic relationships between Australian Angora/Angora_Aus/ and Cashmere/Cashmere_Aus/ populations and three Mongolian Cashmere goat (Bayandelger/BD/, Zavkhan Buural/ZB/, and Gobi Gurvan Saikhan/GGS/) populations based on variation at fourteen MS loci. The level and pattern of observed and expected heterozygosity and polymorphic information content of the fourteen loci studied across the populations were quite similar and high. Except for SRCRSP07, all studied microsatellites were in Hardy-Weinberg Equilibrium (p<0.001). Moderate genetic variation (7.5%) was found between the five goat populations with 92.5% of total genetic variation attributable to diversity existing between the individuals within each population. The greatest Nei's genetic distances were found between the Angora and four Cashmere populations (0.201-0.276) and the lowest distances were between the Mongolian Cashmere goat populations (0.026-0.031). Compared with other Cashmere goat populations, the GGS (crossbred with Russian Don Goats) population had the smallest pairwise genetic distance from the Australian Angora population (0.192). According to a three-factorial correspondence analysis (CA), the three different Mongolian Cashmere populations could hardly be distinguished from each other.

Genetical Studies on the Lady-beetle, Harmonia axyridis Pallace Population in Korea (한국산무당벌레 Harmonia axyridis Pallace 의 유전학적 연구 1. 조혈반문 및 조혈 벽의 변이에 관하여(I))

  • 강영선;김영진
    • The Korean Journal of Zoology
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    • v.3 no.1
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    • pp.13-18
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    • 1960
  • 1. Author has surveyed the frequency, geographic variation and micro-geographic variation of the elytral pattern types and the elytral edge of the population of lady-beetle, Harmonia axyridis Pallace which was collected in Seoul and the other 6 localities in Korea. 2. The number of specimen collected were 3.051 in which succinea occupied 88.32 % : Axyridis, 1.00% : spectabilis, 6.145 : and Conspicua , 4.545. 3. Of all 84.80% were found to have elytral edge. 4. There was a little difference in compositional proportation of the above four types to population and in the frequency of elytral edge between the population of west seaside and that of inland of Korea. 5. An interesting micro-geographic variation was observed in Dae-Chun, a beach located on west seaside of south Korea. In this locality , the Succinea occupied 45.23% and 27.805 were found to be provided with elytral edge in the specimen collected in pine trees ( Pinus thunbergii Parlatore), while in the specimen collected in burley field, oak, willow etc. 92.00% were Succinea and 90.93% were found to have elytral edge.

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Genetic Variation and Population Structure of Alder (Alnus hirsuta : Betulaceae) in Korea

  • Park, Joo-Soo;Huh, Man-Kyu
    • Journal of Life Science
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    • v.10 no.1
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    • pp.14-19
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    • 2000
  • Variation at 25 allozyme loci in Korean wateralder (Alnus hirsuta Rupr.) from nine distinct populations was measured to estimate the amount and pattern of genetic diversity and population structure. The mean genetic diversity within population was 0.166. Korean alder populations have slightly high levels of genetic diversity compared to those present in associated temperature-zone species and two Canadian alder species. Among population s genetic differentiation accounted for an significant 9% of the total variation. High gene flow(Nm=2.63) was observed. Analysis of fixation indices, calculated for all polymorphic loci in each population, showed a substantial deficiency of heterozygotes relative to Hardy-Weinberg expectations. The mean GST value A. hirsuta in Korea (GST = 0.087) is similar to those of A. rogosa in Canada (GST = 0.052). These low values of GST in two countries. reflecting little spatial genetic differentiation, may indicate extensive gene flow (via pollen and/or seeds) and/or recent colonization. These factors reduce the effect of geographic isolation of breeding and the chance for genetic divergence. A pattern of increasing is observed with increasing rainfall per year. Regression analysis indicates that 54% (F = 4.67) of the variability observed can be explained by this relationship.

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