• Journal of Plant Biotechnology
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• v.7 no.2
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• pp.105-112
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• 2005

Buffer soluble protein and five isozymes were analyzed to assess the inter specific relationship among 25 species of the genus Mammillaria Haw. A total of 102 types of proteins were resolved, out of which eighty-six types were found to be polymorphic and only two were unique. A total of 248 bands (isoforms) were detected for 5 isozymes, among them only 4 were found to be monomorphic and 35 were exclusive. Mantel 'Z' statistics revealed wide variations in the correlation among different enzymes. The correlation value 'r' was the highest in case of esterase with pooled data of all the five enzymes. The dendrogram constructed on the basis of pooled data (protein and allozyme) divided the species into two major clusters containing 14 and 11 members respectively. The species M. matudae and M. bella were found to be the most closely related while M. decipience and M. camptroticha were distantly apart. The present study gave an indication of usefulness of the isozyme and protein markers for genetic discrimination between different species of Mammillaria.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.256-262
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• 1999

To evaluate the genetic diversity and structure of the South Korean soybean population, 233 landraces collected in various regions of the country were surveyed for 15 allozyme loci and one protein locus. The South Korean population was fixed or nearly fixed at seven of the 16 loci tested. The number of alleles per locus was 2.06 and Nei’s gene diversity was 0.194. These values were lower than the values for the same 16 loci previously reported for the Japanese and Chinese populations. The differences among eight regional groups were not so marked, with only 7.2% of the total variation arising from regional differentiation. Three southern regional groups (Chollabuk-do, Chollanam-do and Kyong-sangnam-do) exhibited a relatively high variability because of frequent occurrence of alleles characteristic of the Japanese population. A marked difference was found in allelic frequencies at the Dial locus between large-seeded landraces and small-seeded ones, suggesting that the latter, which are used mainly for bean sprouts, had been established independently of the former, which are used mostly for soy sauce and cooking with rice. Not only the region but also the usage as food materials should therefore be taken into consideration in designing an efficient collection and preservation method for the Korean soybean landraces.

• Journal of Environmental Science International
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• v.7 no.3
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• pp.243-250
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• 1998

We examined the genetic variation within the species, the patterns of genetic diversty between populations, thermostability variations of enzymes and temperature tolerances of Corbicula japonica from the two main rivers In Korea. Starch gel electrophoresis was used to examine the genetic variation of 22 locl. Henting experiments of electrophoresis under the condition of 40$\pm$5$^{\circ}$ for 15$\pm$5 min disclose thermostabllity differences, called heat-sensitive and heat-resistant types, within each 디ectrophoretic allozyme. Genetic diversity at the natural species level was high (77.3%), whereas the extent of heat-treat groups was relatively low (52.6%). The genetic diversity trends to decrease from the source of two main siderable high genetic diversity compared with a mean value of C. japonica species, It is recommended that several populations of the species in Korea should be preserved.

• Journal of Life Science
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• v.18 no.11
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• pp.1465-1470
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• 2008

Salix koriyanagi is a deciduous shrub and native to Korea. The spatial distribution of multilocus allelic frequencies and geographical distances of the natural population in upper swampy area at the Namgang River in Korea were studied. The species showed a significant positive and negative spatial autocorrelation according to geographical distances as measured by Moran's I. Genetic similarity of individuals was found among subpopulations at up to a scale of a 12 m distance, and this was partly due to a combination of allelic frequencies, and therefore, a significant spatial autocorrelation was composed of a scale of 12 m intervals. Within S. koriyanagi in swampy area at the Namgang River, a strong spatial structure was observed for allozyme markers, indicating a migration within subpopulations.

• The Korean Journal of Malacology
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• v.14 no.1
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• pp.33-40
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• 1998

A horizontal starch gel electrophoresis for enzyme proteins extracted from 2 species of Korean viviparid snails; Cipangopaludina chinensis malleata and C. japonica was carried out in order to elucidate their genetic relationships. A total of 10 enzymes were employed in three different kinds of buffer systems. Two loci from each enzyme of alcohol dehydrogenase, esterase, glucose phosphate isomerase, isocitrate dehydrogenase, iditol dehydrogenase, malate dehydrogenase and peptidase(VL); and only one locus dach from two enzymes, glycerlo-3-phosphate dehydrogenase and phosphoglucomutase were detected; but, four loci from peptidase(LGG) were observed. Most of loci in two viviparid species showed homozygous monomorphic banding patterns and some of them were specific as genetic markers between two different species. However, EST-1, MDH-1, PEP(VL)-1loci showed polymorphic banding patterns. Foru populations of C. chinensis malleata were more closely clustered in a dendrogram within the range of genetic identity values of 0.928-1.00, and these clusters were lineated with C. japonica at the value of 0.355. In summarizing the above results, two viviparid snail species dmployed in this study mostly showed monomorphic enzyme protein banding patterns, and genetic differences specific between two species.

• Korean Journal of Plant Taxonomy
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• v.39 no.3
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• pp.125-129
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• 2009

The genetic diversity plays a significant role in determining a species' survival and perseverance. Endangered species often lack genetic variation, which makes them vulnerable to numerous dangers of extinction including selection, genetic drifts and human interference. Knowing an endangered species' genetic background greatly enhances conservation efforts since it reveals why, what and how to conserve that species. Cotoneaster wilsonii is an endangered plant species endemic to Ulleung island, but not enough genetic research has been done on this taxon for its effective conservation plans. In this study, three populations of C. wilsonii in Ulleung island underwent allozyme analysis through starch gel electrophoresis. 10 loci were analyzed and F-statistics was calculated. Overall data indicated that C. wilsonii possessed low genetic diversity with intense inbreeding, heterozygote deficiency and low differentiation among populations. These results implied that C. wilsonii was recently introduced to the Ulleung island from ancestor species, and did not have much time to differentiate. Current status of C. wilsonii habitats is very fragile and vulnerable, with increasing tourism constantly threatening the species' survival. It is very likely that C. wilsonii will become extinct in near future unless organized conservation protects its populations and genetic diversity.

• Korean Journal of Plant Taxonomy
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• v.42 no.4
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• pp.267-274
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• 2012

To understand morphological and genetic differentiation between Euphorbia esula and E. maackii we examined 12 morphological characters and 11 isozyme loci from 14 populations of two species. Species of E. esula complex (A = 1.63, P = 44.83, $H_e$ = 0.198) in Korea maintain nearly as high as the genetic diversity reported in East Asian E. jolkinii and E. fauriei while lower than those of E. ebracteolata and E. pekinensis in Korea. Although the ranges of most morphological character variation of the two species overlap, E. esula and E. maackii were well recognized by the combination of the morphological traits, and the result of UPGMA phenogram supports the two distinct species inhibited in Korea. However, isozyme data do not support the recognition of E. esula and E. maackii. The discordance between morphological and allozyme data should be explained by the recent divergence or gene flow via introgressive hybridization between two species.

• Journal of Plant Biology
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• v.38 no.2
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• pp.173-180
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• 1995

We investigated levels and distribution of genetic variation in Korean populations of Calystegia soldanella and C. japonica, clonally reproducing herbaceous perennials. Calystegia soldanella is one ofecologically important beach plants growing only on sand and beach dunes in Europe, East Asia, the Pacific Islands, and the west coast of North America. In contrast, C. japonica usually grows on small mounds of paddy fields, roadsides, and waste places with patchy distribution. Starch gel electrophoresis was conducted on leaves collected from 13 populations of C. soldanella and eight populations of C. japonica. The levels of genetic variation of the two species are very comparable; means of expected heterozygosity (Hep) were 0.100 and 0.099 for C. soldanella and C. japonica, respectively. These values were also very similar to those for species with similar life-history and ecological traits. However, the proportion of total genetic diversity partitioned among populations (GST) of C. soldanella (0.146) was considerably lower than that of C. japonica (0.383). In addition, means of Nei's genetic identity (Ⅰ) for C. soldanella and C. japonica were 0.985 and 0.900, respectively, which supports a restricted gene flow resulting from obligate clonal reproduction of C. japonica. Significant differences in allele frequency were detected among populations at eight and nine of nine polymorphic loci for C. soldanella and C. japonica (P<0.01), respecitvely. Considering the ecological importance of C. soldanella, the isolated beach populations coupled with present destruction of natural habitats of the species may result in erosion of genetic diversity in the near future. In this respect, conservation efforts should be focused on those populations that currently maintain the most genetic diversity such as those populations in the eastern and southeastern Korean Peninsula and Hamduck Beach, Cheju Island.

• Journal of Korean Society of Forest Science
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• v.82 no.2
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• pp.166-175
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• 1993

The genetic variation patterns at 23 loci coding for 16 isozymes in eight natural populations of Pinus densiflora for. erects distributed in Kangwon-Kyungbuk region and 17 populations of Pinus densiflora and 13 populations of Pinus thunbergii were compared. The absence of marker alleles specific to P. thunbergii and almost the same allele-frequency distributions to those of P. densiflora did not support the hypothesis that P. densiflora for. erecta is a introgressive hybrid between P. densiflora and P. thunbergii. From the results of the hierarchial analysis of population differentiation using Wright's F statistics(1978), the frequency distributions of single-locus distance coefficients and other genetic analysis (genetic distance, cluster analysis, factor analysis, resin duct analysis), it was concluded that Pinus densiflora for. erecta cannot be treated genetically as a distinct group from other natural populations of P. densiflora.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.235-243
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• 2001

Genetic variation of the beet armyworm, Spodoptera exigua (Hubner), was analyzed by polymorphic allozymes. Field populations were subdivided by different hosts, geographical locations, and seasons. Estimated average heterozygosity ($0.443\pm$0.013) indicated high genetic variation in all field populations of S. exigua. There were significant inbreeding effects deviated from Hardy-Weinberg equilibrium in each of subpopulations. These significant nonrandom matings were caused by within-subpopulations probably due to sampling errors, but not by mating isolation among subpopulations. Wrights ($F_{ST}$ ) and Neis (D) genetic distances indicated little genetic differentiation among subpopulations, though some southern local subpopulations (Haenam and Sachon) were relatively different of northern subpopulations (Andong and Kunwi). Estimated number of migrants per generation was 5.9 among host subpopulations, 10.6 among geographical subpopulations, and 31.8 among seasonal subpopulations. These genetic analyses suggest that Korean S. exigua subpopulations have little genetic differentiation mostly due to their significant migratory capacity.