• Journal of Microbiology and Biotechnology
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• v.8 no.5
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• pp.490-496
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• 1998

Random amplified polymorphic DNA (RAPD) markers were used to survey genetic variability among 34 Botrytis cinerea isolates from nine different host plants in Korea. For RAPD analysis, 115 arbitrary decamer primers were initially screened for polymorphic major DNA bands with 11 representative B. cinerea isolates. Eleven primers that initially detected polymorphisms were tested a second time with additional 23 isolates of B. cinerea as well as one isolate of Botrytis squamosa as an outgroup. The RAPD analyses revealed that all isolates except one showed different molecular phenotypes. Dendrograms obtained from dissimilarity matrices using the unweighted paired group method of arithmetic means (UPGMA) showed the 36.4% to 90.0% similarity among all B. cinerea isolates. The B. squamosa isolate showed the least similarity to all B. cinerea isolates. The cluster analyses indicated no correlation among all the characteristics examined including molecular phenotypes, host and geographic origins, year of isolation, or pathogenicity. The RAPD data suggest that a high level of genetic variation exists among Korean populations of B. cinerea and it seems to be caused by heterokaryosis among preexisting molecular phenotypes.

• Mycobiology
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• v.29 no.2
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• pp.80-84
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• 2001

Nine species of genus Ganoderma different in cultural characteristics each other were separated by histo-anatomical differences. Differences among the species and geographic distribution of G. lucidum were also analyzed to provide the criteria for the classification of Korean cultivation or wild type strains. Korean cultivation and wild type strains were quiet different from other species as well as Taiwan and North American G. lucidum strains in histo-anatomical traits of Ganoderma. Pore color of Korean G. lucidum strains was less brown than those of Taiwan and North American strains. Shapes of pores were round or circular in Korean strains but ellipsoidal or angular in Taiwan or North American strains. Pore numbers of Korean strains were more than those($4{\sim}6/mm$) of Taiwan or North American strains. Hardness of the pileus of Korean strains was much more than that of Taiwan or North American strains. Such characteristics of Korean strains were different from those of other species of Ganoderma. Korean G. lucidum strains could be classified into the other group because they had many different traits in growth characteristics of fruiting bodies and histo-anatomical characteristics from those of Taiwan or North American G. lucidum and other species of G. lucidum complex.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.112.1-112
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• 2003

Genetic diversity of Plasmodiophora brassicae from major chinese cabbage cultivating areas in Korea was analyzed by using PCR-RFLP and RAPD. Single spores of P brassicae isolated from galls of club root made induce lesion on chinese cabbage successfully. The PCR-RFLP and RAPD by primers PbITS, URP 3, 6 and OPA 7 revealed that single spore isolates showed various DNA polymorphisms among them unrelated geographic origins. These results indicate that P. brassicae population in Korea showed genetic difference among them. This study could be facilitate to identify genetic characteristics ofP. brassicae based on DNA polymorphisms between single spore isolates and to get basic information which can be used to advanced resistance breeding against club root of chinese cabbage.

• ALGAE
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• v.31 no.4
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• pp.303-315
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• 2016

Compsopogon specimens collected in China were examined based on morphology and DNA sequences. Five molecular markers from different genome compartments including rbcL, COI, 18S rDNA, psbA, and UPA were identified and used to construct a phylogenetic relationship. Phylogenetic analyses indicated that two different morphological types from China clustered into an independent clade with Compsopogon specimens when compared to other global samples. The Compsopogon clade exhibited robust support values, revealing the affiliation of the samples to Compsopogon caeruleus. Although the samples were distributed in a close geographical area, unexpected sequence divergences between the Chinese samples implied that they were introduced by different dispersal events and from varied origins. It was speculated that Compsopogon originated in North America, a portion of the Laurentia landmass situated in the Rodinia supercontinent at approximately 573.89-1,701.50 million years ago during the Proterozoic era.Although Compsopogonhad evolved for a rather long time, genetic conservation had limited its variability and rate of evolution, resulting in the current monospecific global distribution. Additional global specimens and sequence information were required to increase our understanding of the evolutionary history of this ancient red algal lineage.

• Korean Journal Plant Pathology
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• v.13 no.1
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• pp.5-12
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• 1997

Genetic diversity of forty-four strains of Xanthomonas campestris pv. vesicatoria from diverse geographic origins was investigated using random amplified polymorphic DNA (RAPD) of genomic DNA. One hundred and thirty-seven amplified fragments were produced by polymerase chain reaction with a set of 14 random primers, and the sizes of amplified DNA fragments ranged approximately from 0.3 to 3.2 kb. Cluster analysis of genetic similarity among the strains generated the dendrogram that clearly separated all strains from each other. The 44 strains of X. campestris pv. vesicatoria were classified into 4 major genomic DNA RAPD groups and 15 subgroups at the genetic similarity of 0.60 and 0.92, respectively. The strains from foreign countries formed discrete subgroups, but the United States strain 87-77 clustered closely with some of Korean strains together. Thirty-nine Korean strains were classified into 11 subgroups, and especially Masan strain Ms93-1 clustered distinctly far from the other Korean strains. RAPD polymorphism suggests strongly the occurrence of genetic differentiation of X. campestris pv. vesicatoria and the existence of genetically distinctive subgroups among the populations in Korea.

• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.334-339
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• 1999

More innovative molecular markers were investigated for rapid and consistent differentiation of Metarhizium anisopliae var. majus from M. anisopliae var. anisopliae. A total of 28 isolates were obtained from various countries and hosts: 13 isolates of M. anisopliae var. anisopliae, 12 isolates of M. anisopliae var. majus, and 3 isolates of M. anisopliae collected in Korea. This study involved restriction enzyme digestions of a PCR product amplified from nuclear internally transcribed spacer (ITS) and a portion of the 28S rDNA regions. Among 11 different restriction enzymes used in this study, MboⅠ digestion particularly produced a restriction pattern that had characteristics of M. anisopliae var. majus. This restriction pattern was consistent in all isolates of M. anisopliae var. majus regardless of their geographic origins and insect hosts. Mapping experiments revealed that MboⅠ sites of M. anisopliae var. majus are identical to those of M. anisopliae var. anisopliae with an exception for the presence of an additional site in the PCR product. Results from this study provide an additional method for identification and differentiation of isolates of these two varieties of M. anisopliae for use in the field and laboratory experiments.

• The Plant Pathology Journal
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• v.27 no.2
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• pp.128-137
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• 2011

Fifty two Macrophomina phaseolina isolates were recovered from 24 host plant species through the 14 Iranian provinces. All isolates were confirmed to species using species-specific primers. The colony characteristics of each isolate were recorded, including chlorate phenotype, relative growth rate at $30^{\circ}C$ and $37^{\circ}C$, average size of microsclerotia, and time to microsclerotia formation. The feathery colony phenotype was the most common (63.7%) on the chlorate selective medium and represented the chlorate sensitive phenotype of the Iranian Macrophomina phaseolina population. Meantime, inter simple sequence repeats (ISSR) Markers were used to assess the genetic diversity of the fungus. Unweighted pair-group method using arithmetic means (UPGMA) clustering of data showed that isolates did not clearly differentiate to the specific group according to the host or geographical origins, however, usually the isolates from the same host or the same geographic origin tend to group nearly. Our results did not show a correlation between the genetic diversity based on the ISSR and phenotypic characteristics. Similar to the M. phaseolina populations in the other countries, the Iranian isolates were highly diverse based on the phenotypic and the genotypic characteristics investigated and needs more studies using neutral molecular tools to get a deeper insight into this complex species.

• Korean Journal Plant Pathology
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• v.10 no.2
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• pp.92-98
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• 1994

Phytophthora infestans populations collected from various geographical locations of Korea in 1991 and 1993 were analyzed for mating types and responses to metalaxyl. Both A1 and A2 mating type isolates were detected in 1991. The majority of the isolates were A2 mating type, but no A1 mating type was detected in 1993. About 40% of the isolates collected in 1991 were resistant to metalaxyl, and the distribution of metalaxyl-resistant isolates of P. infestans was strongly associated with their geographic origins in Korea. Metalaxyl-resistant isolates with EC50 values > 50$\mu\textrm{g}$/ml were collected from the northern provinces of Kangwon, Kyungbuk, and Chonbuk, but not from the southern provinces of Kyungnam, Chonnam, and Jeju in 1991. The drastic increase in the degree of quantitative resistance to metalaxyl was detected among the isolates from the southern provinces during 1991~1993. More than 50% of the isolates collected from the southern provinces of Kyungnam and Chonnam in 1993 had EC50 values >50$\mu\textrm{g}$/ml. The province of Kangwon had isolates with the greatest resistance to metalaxyl. this alpine areas might be the origin of metalaxyl-resistant isolates of P. infestans in Korea. The A2 genotype with metalaxyl resistance appears to be displacing the A1 genotype which is presently the predominant genotype in Korea.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.4
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• pp.309-317
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• 2007

Cadastral control points in Korea are refered to various origins, for example an early separated small triangulation, a separated small triangulation, a separated control surveying origin and an unified origin. Cadastral map with early separated small triangulation origin have difficulties to connect with national GIS data by refered an unified origin. We determined transformation parameters from old origin to unified origin using 2D conformal transformation method. To evaluate of transformation accuracy, we compared with GPS field surveying results. And we experiment on coordinate transformations with unified results between the local geodetic datum and the new Korea geodetic datum.

• Research in Community and Public Health Nursing
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• v.29 no.4
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• pp.476-487
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• 2018

Purpose: The present study is focused on understanding weight perception related with individual- and school-level multifactorial origins, underestimated and overestimated respectively, in normal body weight adolescents. Methods: Using the 2017 Korea Youth Risk Behavior Web-based Survey data of 45,902 students from 799 secondary schools, a multilevel multinomial logistic regression analysis was performed where adolescents (level1) were nested within schools (level 2). Results: At the school level, the average school body mass index (BMI, $kg/m^2$) and physical education were associated with weight perception among both boys and girls. In boys, geographic areas were associated with weight underestimation. At the individual level, perceived economic status, weekly allowance, BMI ($kg/m^2$), smartphone usage time (hrs/day) and perceived stress were associated with weight perception among both boys and girls. Age, paternal education, academic achievement and alcohol use were associated with weight perception among girls, while part-time job and physical activity were associated with weight perception among boys. Conclusion: Our findings underscore the importance of individual- and school-level environments in developing correct weight perception and have implications for school health education to establish healthy lifestyle behaviors for all adolescents.