• Journal of Marine Life Science
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• v.4 no.1
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• pp.22-28
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• 2019

The bacterial diversity of an Antarctic hard coral, Errina fissurata, was examined by isolating bacterial colonies from crushed coral tissue and by sequencing their 16S rRNA gene. From the analyzed results, the bacteria were classified as Actinobacteria (56%), Firmicutes (35%) and Proteobacteria (9%). The thirty-four isolates were cultured in liquid media at different temperatures and their growth was assessed over time. The majority of the isolates displayed their highest growth rate at 25℃ during the first three days of cultivation, even though the coral was from a cold environment. Nevertheless, strains showing their highest growth rate at low temperatures (15℃ and 4℃) were also found. This study reports the composition of an Antarctic hard coral-associated culturable bacterial community and their growth behavior at different temperatures.

• Journal of Ginseng Research
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• v.40 no.1
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• pp.28-37
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• 2016

Background: Panax ginseng cannot be cultivated on the same land consecutively for an extended period, and the underlying mechanism regarding microorganisms is still being explored. Methods: Polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) and BIO-LOG methods were used to evaluate the microbial genetic and functional diversity associated with the P. ginseng rhizosphere soil in various cultivation ages and modes. Results: The analysis of microbial diversity using PCR-DGGE showed that microbial communities were significantly variable in composition, of which six bacterial phyla and seven fungal classes were detected in P. ginseng soil. Among them, Proteobacteria and Hypocreales dominated. Fusarium oxysporum, a soilborne pathogen, was found in all P. ginseng soil samples except R0. The results from functional diversity suggested that the microbial metabolic diversity of fallow soil abandoned in 2003was the maximum and transplanted soil was higher than direct-seeding soil and the forest soil uncultivated P. ginseng, whereas the increase in cultivation ages in the same mode led to decreases in microbial diversity in P. ginseng soil. Carbohydrates, amino acids, and polymers were the main carbon sources utilized. Furthermore, the microbial diversity index and multivariate comparisons indicated that the augmentation of P. ginseng cultivation ages resulted in decreased bacterial diversity and increased fungal diversity, whereas microbial diversity was improved strikingly in transplanted soil and fallow soil abandoned for at least one decade. Conclusion: The key factors for discontinuous P. ginseng cultivation were the lack of balance in rhizosphere microbial communities and the outbreak of soilborne diseases caused by the accumulation of its root exudates.

• Journal of Ginseng Research
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• v.41 no.3
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• pp.353-360
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• 2017

Background: Endophytic fungi play an important role in balancing the ecosystem and boosting host growth. In the present study, we investigated the endophytic fungal diversity of healthy Panax notoginseng and evaluated its potential antimicrobial activity against five major phytopathogens causing root-rot of P. notoginseng. Methods: A culture-dependent technique, combining morphological and molecular methods, was used to analyze endophytic fungal diversity. A double-layer agar technique was used to challenge the phytopathogens of P. notoginseng. Results: A total of 89 fungi were obtained from the roots, stems, leaves, and seeds of P. notoginseng, and 41 isolates representing different morphotypes were selected for taxonomic characterization. The fungal isolates belonged to Ascomycota (96.6%) and Zygomycota (3.4%). All isolates were classified to 23 genera and an unknown taxon belonging to Sordariomycetes. The number of isolates obtained from different tissues ranged from 12 to 42 for leaves and roots, respectively. The selected endophytic fungal isolates were challenged by the root-rot pathogens Alternaria panax, Fusarium oxysporum, Fusarium solani, Phoma herbarum, and Mycocentrospora acerina. Twenty-six of the 41 isolates (63.4%) exhibited activity against at least one of the pathogens tested. Conclusion: Our results suggested that P. notoginseng harbors diversified endophytic fungi that would provide a basis for the identification of new bioactive compounds, and for effective biocontrol of notoginseng root rot.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.9
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• pp.833-840
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• 2017

This study was attempted to explore in depth the education of cultural diversity in the curriculum and textbooks of middle school according to [1] As a result, the educational goals in the curriculum emphasized[2] the realization of the meaning and value of cultural diversity education reflecting the global citizen education in various time, space background and socio-cultural context. The purpose of the curriculum guidelines is specified, and the following is given: "To properly recognize the diversity of the world culture; To acquire knowledge on cultural diversity; To grasp important functions in the city life, and to have attitudes and qualities required as members of the world, and to develop a pluralistic literacy ability''. In the textbooks, the subjects of the cultural diversity education are mainly based on the curriculum standards, the education area of the 7th grade is the 'human community life', the education area of the 8th grade is the origin and development of the Chinese civilization, Suggesting the scope of the theme 'harmonious coexistence with the world'. In order to analyze cultural diversity education in response to the demands of the times, we analyzed three factors such as diversity, identity, and interrelationship.

• Journal of Advanced Navigation Technology
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• v.22 no.4
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• pp.247-263
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• 2018

In this article, it is that have highlighted the importance of the creative communication, convergence and identity of airport operations. This research verifies to influence in the airport performance by the diversity, mediator effect of creativity, and moderator effect of the public enterprise management evaluation performed degree in the operation of the airport. This study design how participants were selected as study the employees from two airports on the enterprise of the Incheon International Airport, Gimpo International Airport in Korea using the simple random sampling method. The findings indicate that the positively internal diversity, mediated creativity, and moderated public enterprise management evaluation performed degree affects performance of airports. This research provides a few implications and insights in the operation of airport.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.575-582
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• 2018

Bacterial fruit blotch (BFB) caused by Acidovorax citrulli is a devastating disease found in many cucurbits cultivation fields. The genetic diversity for 29 strains of A. citrulli collected from various cucurbits in South Korea was determined by DNA fingerprinting with a pathogenicity test, multi locus analysis, Rep-PCR (repetitive sequence polymerase chain reaction), and URP (universal rice primers) PCR bands. Two distinct groups (Korean Clonal Complex, KCC1 and KCC2) in the population were identified based on group specific genetic variation in the multi locus phylogeny using six conserved loci and showed a very high similarity with DNA sequences for representative foreign groups [the group I (CC1-1 type) and the group II (CC2-5 type)] widely distributed worldwide, respectively. Additionally, in the case of phaC, a new genotype was found within each Korean group. The KCC1 was more heterogeneous compared to the KCC2. The KCC1 recovered mainly from melons and watermelons (ratio of 6 : 3) and 15 of the 20 KCC2 strains recovered from watermelons were dominant in the pathogen population. Accordingly, this study found that two distinct groups of differentiated A. citrulli exist in South Korea, genetically very similar to representative foreign groups, with a new genotype in each group resulting in their genetic diversity.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.2
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• pp.176-182
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• 2019

Objective: This study was conducted to investigate basic information on genetic structure and characteristics of Limousin population in Hungary. Obtained results will be taken into consideration when adopting the new breeding strategy by the Association of Hungarian Limousin and Blonde d'Aquitaine Breeders (AHLBB). Methods: Genetic diversity and phylogenetic relationship of 3,443 Limousin cattle from 16 different herds were investigated by performing genotyping using 18 microsatellite markers. Amplified DNA was genotyped using an automated genetic analyzer. Results: Mean of effective alleles ($n_e$) of the populations was 3.77. Population C had the lowest number of effective alleles (3.01) and the lowest inbreeding coefficient ($F_{IS}$) value (-0.15). Principal component analysis of estimated genetic distance ($F_{ST}$) values (p<0.000) revealed two herds (C and E) distinct from the majority of other Limousin herds. The pairwise $F_{ST}$ values of population C compared to the others (0.066 to 0.120) fell into the range of moderate genetic distance: 0.050 to 0.150, while population E displayed also moderate genetic distance ($F_{ST}$ values in range 0.052 to 0.064) but only to six populations (G, H, J, L, N, and P). $F_{ST(C-E)}$ was 0.148, all other pairs -excluding C and E herds- displayed low genetic distance ($F_{ST}$<0.049). Population D, F, I, J, K, L, N, O, and P carried private alleles, which alleles belonged to 1.1% of the individuals. Most probable number of clusters (K) were 2 and 7 determined by Structure and BAPS software. Conclusion: This study showed useful genetic diversity and phylogenetic relationship data that can be utilized for the development of a new breeding strategy by AHLBB. The results presented could also contribute to the proper selection of animals for further whole genome scan studies of Limousins.

• Mycobiology
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• v.49 no.4
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• pp.376-384
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• 2021

Agaricus bisporus is a popular edible mushroom that is cultivated worldwide. Due to its secondary homothallic nature, cultivated A. bisporus strains have low genetic diversity, and breeding novel strains is challenging. The aim of this study was to investigate the genetic diversity and population structure of globally collected A. bisporus strains using simple sequence repeat (SSR) markers. Agaricus bisporus strains were divided based on genetic distance-based groups and model-based subpopulations. The major allele frequency (MAF), number of genotypes (NG), number of alleles (NA), observed heterozygosity (HO), expected heterozygosity (HE), and polymorphic information content (PIC) were calculated, and genetic distance, population structure, genetic differentiation, and Hardy-Weinberg equilibrium (HWE) were assessed. Strains were divided into two groups by distance-based analysis and into three subpopulations by model-based analysis. Strains in subpopulations POP A and POP B were included in Group I, and strains in subpopulation POP C were included in Group II. Genetic differentiation between strains was 99%. Marker AB-gSSR-1057 in Group II and subpopulation POP C was confirmed to be in HWE. These results will enhance A. bisporus breeding programs and support the protection of genetic resources.

• The Korean Journal of Mycology
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• v.48 no.4
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• pp.457-473
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• 2020

We investigated the distribution and diversity of fungi in brackish water and soil from the Eulsukdo Island, Geumgang Estuary Bank, Suncheon Bay, Dae-ho Tide Embankment and coastal sand dune in Sinduri and Bu-nam Tide Embankment, Korea. Fungi were isolated from water samples by hand-pumped filtration, and soil samples were collected and diluted. The isolated fungi were incubated in potato dextrose agar at 25℃. A total of 173 fungal strains were isolated from brackish water and identified according to their respective internal transcribed spacer via phylogenetic analysis. The diversity of all fungal strains was analyzed according to diversity indices. The fungal strains belonged to any of 18 taxonomic orders: Pleosporales, Eurotiales, Capnodiales, Hypocreales, Polyporales, Saccharomycetales, Agaricales, Glomerellales, Mucorales, Dothideales, Russulales, Xylariales, Sordariales, Myrmecridiales, Tubeufiales, Onygenales, Cantharellales, and Amphisphaeriales. Cladosporium spp. (20%), Penicillium spp. (19%), and Fusarium sp. (5%) comprised majority of the identified strains. Two species from the fungal isolates were newly identified in Korea: Sarocladium kiliense NNIBRFG3280 and Fusicolla merismoides NNIBRFG23708.

• Journal of Life Science
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• v.22 no.4
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• pp.466-471
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• 2012

Sixty individuals of the scallop $Patinopecten$ $yessoensis$ (Genus Pecten) were sampled to examine the genetic diversity and population structure of this species. Random amplified polymorphic DNA (RAPD) identified 109 genotypes and produced 79 polymorphic loci (72.8%). Total genetic diversity values ($H_T$) and interlocus variation in the within-population genetic diversity ($H_S$) were 0.254 and 0.178, respectively. On a per-locus basis, the proportion of total genetic variation due to differences among populations ($G_{ST}$) was 0.299. This indicated that about 70.1% of the total variation was within populations. The unique loci and bands of $P.$ $yessoensis$ were shown in only one population among the three countries. RAPD markers were very effective in classifying the natural population levels of $P.$ $yessoensis$ in Korea, China, and Japan. In addition, insights into the relative gene diversity among and within populations of $P.$ $yessoensis$ would be useful in breeding and for the development of strategies for animal genetic resources.