• Journal of Plant Biotechnology
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• 제43권2호
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• pp.174-180
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• 2016

Licorice plant (Glycyrrhiza spp.) is an important herb, but the major portion of the national demand is imported to Korea because the domestic production base is vulnerable. We performed basic molecular breeding research for domestic cultivation and production. All publicly available G. uralensis EST sequences, which totaled 56,089, were assembled into 4,821 unigenes and examined for microsatellites. Eight polymorphic microsatellite loci were identified and 16 G. uralensis and 6 G. glabra accessions, which were collected from different locations, were genotyped using the microsatellites. Genetic diversity within the accessions was estimated by construction of a dendrogram. The dendrogram was clustered into two groups. The results showed that there is a correlative genetic relationship between species. The microsatellite markers were found to be useful for diversity analysis as they are able to successfully distinguish the Glycyrrhiza accessions.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.212-212
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• 2022

Soluble starch synthase (SS) IV-2 is one of the starch synthase gene family members and responsible for starch chain elongation interacting with other rice eating and cooking quality controlling genes (e.g., AGPlar and PUL). SSIV-2 is mainly expressed in leaves, especially at grain-filling stage and its alleles can significantly affect rice quality. Here, we investigated the genetic diversity and population structure analyses of SSIV-2 gene by using 374 rice accessions. This rice set was grouped into 320 cultivated bred (subsequently classified into temperate japonica, indica, tropical japonica, aus, aromatic and admixture) and 54 wild rice. Haplotyping of cultivated rice accessions provided a total of 7 haplotypes, and only three haplotypes are functional indicating four substituted SNPs in two exons of chromosome 5: T/A and G/T in exon 4, and C/G and G/A in exon 13. Including the wild, a highest diverse group (0.0041), nucleotide diversity analysis showed temperate japonica (0.0001) had a lowest diversity value indicating the origin information of this gene evolution. Higher and positive Tajima5s D value of indica (1.9755) indicate a selective signature under balancing selection while temperate japonica (-0.9018) was in lowest Tajima's D value due to a recent selective sweep by positive selection. We found the most diverse genetic components of the wild in PCA but shared in some portion with other cultivated groups. Fixation index (F_ST-values) and phylogenetic analysis indicate a closer relationship of the wild with indica (F_ST=0.256) than to its association to both of temperate japonica (F_ST=0.589). Structure analysis shows a clear separation of cultivated subpopulations at every K value, but genetic components were admixed within the wild illustrating the same genetic background with japonica and indica in some proportion.

• International Journal of Industrial Entomology and Biomaterials
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• 제31권2호
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• pp.62-69
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• 2015

The Asian cavity-nesting honeybee, Apis cerana (Hymenoptera: Apidae), has been extensively studied for its biogeography and genetic diversity, but the molecules utilized in past studies were mainly ~90 bp long mitochondrial non-coding sequences, located between $tRNA^{Leu}$ and COII. Thus, additional molecular markers may enrich our understanding of the biogeography and genetic diversity of this valuable bee species. In this study, we reviewed the public genome database to find introns of cDNA sequences, with the assumption that these introns may have less evolutionary constraints. The six introns selected were subjected to preliminary tests. Thereafter, two introns, titled White gene and MRJP9 gene, were selected. Sequencing of 552 clones from 184 individual bees showed a total of 222 and 141 sequence types in the White gene and MRJP9 gene introns, respectively. The sequence divergence ranged from 0.6% to 7.9% and from 0.26% to 17.6% in the White gene and the MRJP9 introns, respectively, indicating higher sequence divergence in both introns. Analysis of population genetic diversity for 16 populations originating from Korea, China, Vietnam, and Thailand shows that nucleotide diversity (π) ranges from 0.003117 to 0.025837 and from 0.016541 to 0.052468 in the White gene and MRJP9 introns, respectively. The highest π was found in a Vietnamese population for both intron sequences, whereas the nine Korean populations showed moderate to low sequence divergence. Considering the variability and diversity, these intron sequences can be useful as non-mitochondrial DNA-based molecular markers for future studies of population genetics.

• 한국작물학회지
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• 제63권1호
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• pp.1-7
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• 2018

Information on the patterns of genetic diversity and population structure is essential for the rational use and efficient management of germplasms; accurate information aids in monitoring germplasms, and can also be used to predict potential genetic gains. In this study, we assessed genetic diversity, focusing on Korean rice accessions for theand their sustainable conserved diversity. Using DNA profiling with 12 simple sequence repeat (SSR) markers, we detected a total of 333 alleles among 2,016 accessions. The number of alleles ranged from 21 to 53, with an average of 27.8. Average polymorphism information content was 0.797, with the lowest being 0.667 and the highest 0.940. CA cluster analysis and the model-based population structure revealed two main groups that could be subdivided into five subgroups. Analysis of the molecular variance study based on the SSR profile data showed 5% variance among the profiles, whereas we recorded 93% variance among individuals and 2% variance within individuals. Specifically, the utilized diversity for of the breeding program is restricted in that cultivars were located in limited clades. These results revealed that preserving the diversity of Korean landraces could be useful sources for breeding new rice cultivars, and cwould be the basis for the sustainable conservation and utilization of a Korean rice germplasm.

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.447-459
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• 2010

Bacterial diversity of two distinct wastewater treatment systems, conventional activated sludge (CAS) and membrane bioreactor (MBR), of petroleum refineries were investigated through 16S rRNA gene libraries. Sequencing and phylogenetic analysis showed that the bacterial community composition of sludge samples was distinct between the two wastewater treatment systems. MBR clones belonged predominantly to Class Betaproteobacteria, represented mainly by genera Thiobacillus and Thauera, whereas CAS clones were mostly related to Class Alphaproteobacteria, represented by uncultured bacteria related to Order Parvularculales. Richness estimators ACE and Chao revealed that the diversity observed in both libraries at the species level is an underestimate of the total bacterial diversity present in the environment and further sampling would yield an increased observed diversity. Shannon and Simpson diversity indices were different between the libraries and revealed greater bacterial diversity for the MBR library, considering an evolutionary distance of 0.03. LIBSHUFF analyses revealed that MBR and CAS communities were significantly different at the 95% confidence level ($P{\leq}0.05$) for distances $0{\leq}D{\leq}0.20$. This work described, qualitatively and quantitatively, the structure of bacterial communities in industrial-scale MBR and CAS processes of the wastewater treatment system from petroleum refineries and demonstrated clearly differentiated communities responsible for the stable performance of wastewater treatment plants.

• 디지털융복합연구
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• 제12권10호
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• pp.145-156
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• 2014

본 연구의 주요 목적은 조직 내 다양성 관리, 종업원의 이직 의도, 그리고 지각된 조직 후원과의 구조적 관계를 살펴보는 것이다. 또한 조직 내 다양성 관리와 이직 의도 간의 관계에서 지각된 조직 후원의 매개적 역할에 대해서도 살펴보는 것이다. 연구 목적을 달성하기 위해 선행연구 리뷰와 설문지법을 이용한 실증적 분석을 실시하였으며, 연구결과 조직 내 다양성 관리와 종업원의 이직 의도와는 부(-)의 영향관계가 존재하지 않았으나, 다양성 관리가 지각된 조직 후원에는 정(+)의 영향을 미치는 것으로 나타났다. 지각된 조직 후원은 종업원의 이직 의도에 부(-)의 영향을 미치는 것으로 나타났다. 또한 지각된 조직 후원은 조직 내 다양성 관리가 종업원의 이직 의도에 미치는 영향 관계에서 매개역할을 하는 것으로 나타났다. 이러한 연구결과를 바탕으로 종업원의 이직 의도를 줄이고 최종적으로 성과 향상을 위한 방안에 대해 논의하고 시사점을 제시하였다.

• International Journal of Industrial Entomology and Biomaterials
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• 제36권2호
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• pp.31-41
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• 2018

The dung beetle, Copris tripartitus (Coleoptera: Scarabaeidae), is an endangered insect in South Korea. Previously, partial mitochondrial COI and CytB gene sequences have been used to infer genetic diversity and gene flow of this species in South Korea. In this study, we additionally collected C. tripartitus (n = 35) from one previous locality and two new localities, sequenced COI and CytB genes, and combined these with preexisting data for population genetic analysis. Sequence divergence of current samples showed slightly lower values [4.86% (32 bp) for COI and 4.16% (18 bp) for CytB] than that in the previous study. Nucleotide diversity (${\pi}$) ranged from 0.005336 (Gulupdo) to 0.020756 (Seogwi-dong) in COI and 0.009060 (Aewol-eup) to 0.017464 (Seogwi-dong) in CytB. Seogwi-dong samples that showed the highest ${\pi}$ in the previous study also showed the highest ${\pi}$ in this study for both gene sequences. The newly investigated Gulupdo samples had the lowest haplotype diversity for both gene sequences. They also had the lowest ${\pi}$ for COI and the second lowest ${\pi}$ for CytB. On the other hand, the newly added Haean-dong sample had relatively higher diversity estimates. Gene flow among populations was high, although significant difference was only detected between Gulupdo and Anmado or between Gulupdo and Seogwi-dong for COI sequences (P < 0.05). Considering the high genetic diversity and gene flow in C. tripartitus populations, one major issue regarding conservation seems not to be recovery of genetic diversity.

• International Journal of Industrial Entomology and Biomaterials
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• 제47권2호
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• pp.99-114
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• 2023

Patanga japonica Bolívar, 1898 (Orthoptera: Acrididae) is listed as a climate-sensitive indicator species in South Korea and is called southern group of insects in that the main distributional range is southern region of South Korea and Asian continent. In South Korea, thus, the species was distributed mainly in southern region of South Korea including southward a remote Jeju Island, but recently the species has often been detected in mid to northern region of South Korea, implying northward range expansion in response to climate change. Understanding the characteristics of the changes in genetic diversity during range expansion in response to climate change could be a foundation for the understanding of future biodiversity. Thus, in this study, we attempted to understand the changing pattern of the genetic diversity of the P. japonica in newly expanded regions. For the purpose of study, we collected 125 individuals from seven localities throughout South Korea including two newly distributed regions (Pyeongtaek and Yeongwol at ~37° N). These were sequenced for a segment of mitochondrial cytochrome oxidase subunit I (COI) and analyzed for genetic diversity, haplotype frequency, and population genetic structure among populations. Interestingly, northward range expansion accompanied only haplotypes, which are most abundant in the core populations, providing a significant reduction in haplotype diversity, compared to other populations. Moreover, genetic diversity was still lower in the expanded regions, but no genetic isolation was detected. These results suggest that further longer time would take to reach to the comparable genetic diversity of preexisting populations in the expanded regions. Probably, availability of qualified habitats at the newly expanded region could be pivotal for successful northward range expansion in response to climate change.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2002년도 추계학술대회
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• pp.100-105
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• 2002

The diversity of epiphytic bacterial communities on deciduous oak tree (Quercus dentate Thunb.) leaves was examined both in the natural forest area with a clean air and in the industrial estate to assess effects of acidic deposition to the phyllosphere using 16S rDNA sequence data. In addition, acid-tolerant epiphytic bacterial communities were compared. A total of 78 epiphytic and 444 acid-tolerant clones were obtained from clone libraries, resulting in 20 and 17 phylotypes by analysis of restriction fragment length polymorphism (RFLP) for PCR-amplified 16S rDNA products. A low bacterial diversity in both areas was found. As tree leaves grow older, bacterial diversities were slightly increased in the level of subphylum. The community structure of epiphytic bacteria in both areas in April consisted of only two subphyla, $\beta-and\;\gamma-Proteobacteria$. In August two additional subphyla in both areas were found, but the composition was a little different, Acidobacteria and Cytophaga-Flexibacter-Bacteroids (CFB) group in the industrial estate and a -Proteobacteria and CFB group in the natural area, respectively. Acidobacteria could be an indicator of epiphytic bacteria for acidic deposition on plant leaves, whereas a -Proteobacteria be one of epiphytic bacteria that naturally survive on leaves that are not affected by acidic deposition. The acid-tolerant bacterial communities in April were composed of two subphyla, $\gamma-Proteobacteria$ and Low G+C gram-positive bacteria in both areas, and in August a-Proteobacteria was added to the community just in the natural forest area. The direct influence of acidic deposition on the acid-tolerant bacterial phylogenetic composition could not be detected in higher taxonomic levels such as subphylum, but at narrower or finer levels it could be observed by a detection of Xanthomonadales group of $\gamma-Proteobacteria$ just in the industrial estate.

• International Journal of Industrial Entomology and Biomaterials
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• 제24권1호
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• pp.41-47
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• 2012

The Scarites aterrimus (Coleoptera: Carabidae) dwells exclusively on coastal sandy dunes. Previously, we investigated the nation-wide magnitude and nature of genetic diversity of the species using mitochondrial COI gene and found moderate to low magnitude of sequence diversity, the presence of closely related haplotypes, and relatively high gene flow estimate. Based on these observations we concluded that the species had no historical barriers that bolster genetic subdivision and possible population decline. In this study, we additionally sequenced mitochondrial COII gene from 23 individuals collected from 9 Korean localities to confirm previous findings. Sequencing of 688 bp COII gene provided 5 haplotypes ranging in sequence divergence from 0.145% to 0.291% (1 ~ 2 bp), further confirming low sequence divergence of the species. Gene flow estimates and genetic diversity estimates also support the previous findings that there had been no historical barriers that bolster genetic subdivision.