• The Korean Journal of Mycology
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• v.44 no.3
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• pp.196-200
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• 2016

Symptoms of summer patch were observed on Kentucky bluegrass (Poa pratensis L.) cv. "Midnight II" from mid-June in 2015 in Seoul, Korea. The symptoms appeared as leaf blight, root rot, and frog-eye patch, which are typical of summer patch. To identify the causal agent of these symptoms, a pathogen was isolated from diseased leaves and roots, and the cultural, morphological, and phylogenetic characteristics were analyzed. The isolate reached 50-60 mm on potato dextrose agar (PDA) after 10 days as a white-grey mycelium with septa, and became olive-green or brown from the center. Phialide-like structures were observed at the ends of hyphae, and conidia were rarely observed. A phylogenetic analysis was conducted based on large subunit (LSU) and RNA polymerase II large subunit (RPB1) sequences. According to this analysis, the isolated pathogen was confirmed to be Magnaporthiopsis poae. In a pathogenicity test, summer patch symptoms were observed at 20 days after inoculation using the same grass cultivar. This is the first report of summer patch disease caused by M. poae on cool season grass in Korea.

• Korean Journal of Ichthyology
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• v.36 no.2
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• pp.139-155
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• 2024

Using the cytb gene region of the mitochondrial DNA of eight populations of Sarcocheilichthys nigripinnis morii and five populations of S. variegatus wakiyae, which belong to the genus Sarcocheilichthys from Korea, the genetic diversity and molecular phylogenetic relationships of each population were examined. As a result of the analysis, it was confirmed that the S. variegatus wakiyae population had higher genetic diversity than the S. nigripinnis morii population. In the phylogenetic tree of genus Sarcocheilichthys fish in Korea based on the cytb gene, the Yeongsan River (YSR) population of S. variegatus wakiyae forms a clade with the Tamjin River (TJR), Yeongsan River (YSR), and Seomjin River (SJR) population of S. nigripinnis morii, and genetic relationships that do not align with the current classification system were observed. Meanwhile, on the nuclear DNA phylogenetic tree, S. variegatus wakiyae and S. nigripinnis morii could be clearly distinguished, showing mitonuclear inconsistency where mitochondrial and nuclear DNA conflicted on the phylogenetic tree. The Seomjin River (SJR) population of S. nigripinnis morii was translocated to the Dongjin River (DJR) population, haplotype from which crossbreeding was presumed to have occurred was confirmed. Among the rivers flowing into the East Sea, the S. nigripinnis morii population is known to have been introduced and inhabit only the Hyeongsan River (HSR), and it is presumed to be a population formed by translocation from the Han River (HR) population, with a haplotype representing a unique genetic group also confirmed. The Han River (HR), Geum River (GR), and Mangyeong River (MGR) populations of S. nigripinnis morii formed a genetically identical population with S. czerskii and S. soldatovi distributed north of the Yalu River, and accordingly, a taxonomic reexamination was required through morphological and molecular phylogenetic studies by securing various specimens.

• Journal of Animal Science and Technology
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• v.54 no.4
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• pp.241-246
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• 2012

The goal of this study was to verify the phylogenetic status of the Korean native goats (KNG). We determined the complete sequence of the mitochondrial cytochrome b gene in 48 goats among four populations. We also analyzed genetic variability within goats, and a phylogenetic analysis was performed by comparison with other country's goats. Three nucleotide substitutions were detected, and two of these were missense mutations that occurred due to a substitution of amino acid. Four haplotypes were defined from KNG. Three of these haplotypes were only found in the Chinese goat. However, the other haplotype was KNG-specific. In the phylogenetic analysis, four clades (A~D) were classified among domestic goats, and the KNG was classified into clade 1 that estimated as lineage A based on the D-loop sequence. Each haplotype from the KNG was clustered closely with that of the Chinese goat. The results of haplotype distribution and phylogenetic location suggest that strong gene flow occurred from China to the Korean Peninsula.

• Korean Journal of Ichthyology
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• v.22 no.4
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• pp.273-278
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• 2010

Partial nucleotide sequences of nuclear protein-coding recombination activating gene 1 (RAG1) gene of two Abbottina and five Microphysogobio species residing in Korea were analyzed to elucidate the molecular phylogenetic position of A. springeri Banarescu and Nalbant. In RAG1 tree A. rivularis was clearly separated from the monophyletic lineage composed of A. springeri, Biwia zezera and Microphysogobio species. Within this lineage B. zezera showed sister-group relationship to the monophyletic group composed of A. springeri and five Microphysogobio species. Thus, our phylogenetic tree revealed the polyphyletic nature of two Abbottina species from Korea, which result is well congruent with the previous phyletic assumption based on osteological features. The current classification of Abbottina and Microphysogobio based on morphological criteria, such as the presence or absence of papillae on lips and size of swim bladder with or without encapsulation, does not reflect their true evolutionary history.

• Korean Journal of Microbiology
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• v.24 no.4
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• pp.400-405
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• 1986

We have constructed a phylogenetic tree for eleven species by comparing their tRNA sequences. The tree suggests that prokaryotes diverged very early before the emergence of animals. The fact that H. volcano, an archaebacterium, clusters with eukaryotes implied that eukaryotes did not diverge directly from thier common ancestor with eubacteria. The branching order of phage $T_{4}$ and phage $T_{5}$ indicates that they have diverged separately from thier hosts and they might have evolved independently. A correlation between nucleotide substitution in tRNAs and paleontological record was observed. We verified that our phylogenetic tree fits very well with traditional ones very well by imposing the molecular clock on the tree.

• Korean Journal of Plant Taxonomy
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• v.41 no.4
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• pp.338-344
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• 2011

Molecular phylogenetic studies were conducted to evaluate evolutionary trends, relationships and species identities among four species, one variety and one outgroup of the Korean Genus Calystegia. The important characteristics of Calystegia are the shape of the lamina, the length ofthe corolla and the presence of hair. However, many variations were observed as regards the characteristics of the leaf, making true identification difficult. In molecular phylogenetic studies, C. soldanella formed one clade, and it was located mostly in the base. C. hederacea and C. sepium did not form an independent clade in their ITS regions and psbA-trnH regions, and this investigation could not confirm a relationship. Therefore, a relationship between these two species is not sufficiently supported by these markers (ITS and psbA-trnH). Consequently, this research should be achieved through many samples and markers. C. sepium var. japonica and C. dahurica are closely related.

• Korean journal of applied entomology
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• v.37 no.1
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• pp.9-17
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• 1998

Hitherto only one species of Longidorinae, Longidorus sylphus was recorded from Korea by Choi and Moon (1988). Three unrecorded species of Longidorinae, L, litchii, L. himalayensis and Paralongidorus sali were found in Korea for the first time during the systematic study of Dorylaimida from Korea. They are described and illustrated. Some differences are discussed.

• Animal Systematics, Evolution and Diversity
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• v.8 no.2
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• pp.259-278
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• 1992

The zoantharians and ceriantiparians known from the Korea Strait are 21 species, 16 genera, 10 families in 3 orders, of which 6 species are newly recorded to the Korea Strait fauna. Three species of them are new to Korean waters: Flosmaria mustsuensis, Hormathia andersoni and Verrillactis paguri. The specimens were collected from 34 localities of Korea Strait from 1984 to 1991.

• Korean Journal of Microbiology
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• v.52 no.1
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• pp.59-64
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• 2016

In this study, a pyrosequencing was performed and analyzed to verify the phylogenetic diversity of actinomycetes in the bamboo (Sasa borealis) soil as a base study to obtain the genetic resources of actinomycetes. It was found that the rhizosphere soil had much various distribution in bacterial communities showing a diversity of 8.15 with 2,868 OTUs, while the litter layer showed a diversity of 7.55 with 2,588 OTUs. The bacterial community in the bamboo soil was composed of 35 phyla and the predominant phyla were Proteobacteria (51-60%), Bacteroidetes (16-20%), Acidobacteria (4-16%) and Actinobacteria (4-14%). In particular, Actinobacteria including Micromonosporaceae and Streptomycetaceae had a diverse distribution of actinomycetes within the six orders, 35 families and 121 genera, and it was characterized that about 83% of actinomycetes within Actinomycetales belonged to the 28 families. Among the dominant actinobacterial populations, Micromonosporaceae, Pseudonocardiaceae and Streptomycetaceae were representative family groups in the bamboo soils.

• Journal of Conservation Science
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• v.36 no.5
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• pp.405-420
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• 2020

A convergence research was conducted on glass beads excavated at the ruins of Hapgang-ri, Sejong, using the archeology and conservation approach. The period of appearance of Jugu Towangmyo in the ruins of Hapgang-ri can be estimated to begin in the late 2^nd century; for Jugu Towangmyo No. 15, the period spans from the late 2^nd to early 3^rd century. Form, color, and manufacturing techniques of complete glass beads were examined, and the cross-sections and chemical composition of 16 samples were observed. Based on these analyses, the glass beads were divided into blue, purple, and red colors. The blue-colored beads could be further sub-divided based on their gloss and brightness; in contrast, the red-colored beads were highly uniform with regard to these parameters. Based on the stripe and bubble arrangement on the surface of the glass beads, their drawing technique was identified. Traces of heat treatment or polishing were observed at the ends of the beads. According to their chemical composition, the 16 samples were classified into 3 potash glass and 13 soda glass groups; in the latter, the properties of the stabilizers were divided according to the blue and red bead colors. The stabilizers of the red beads are unique in that they allow the distinction among beads excavated in other areas in South Korea owing to their compositional differences. Colorants in blue- and red-colored beads are cobalt (containing MnO), and copper and iron, respectively.