• The Korean Journal of Pesticide Science
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• v.12 no.1
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• pp.97-101
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• 2008

For the isolation of Actinomycetes showing nematocidal activity against Pine wood nematode, Bursaphelenchus xylophilus, about 2000 culture broth of Actinomycetes were tested and their activity were compared with that of Streptomyces avermitilis resulting a selected strain AW050027. The cultural, morphological and physiological analysis was performed for the identification of a selected strain. Phylogenetic analyses based on 165 rDNA gene sequences showed that the selected strain AW050027 belonged to the genus Micromonospora and M. corioriae $NAR01^T$ was the closest neighbors, sharing 98.9% 165 rDNA gene sequence similarity.

• Journal of Forest and Environmental Science
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• v.23 no.1
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• pp.65-71
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• 2007

In early 2000's, about six Phytophthora species have been newly described leading mortality on coniferous and broad-leaved trees in forests. Also, some species of Phytophthora are responsible for ink disease in chestnut plantation near or within forests. Similar symptoms of ink disease were appeared in some areas of Kyungnam and Jeonnam providences in 2005, and the pathogen was isolated using Phytophthora- selective medium in 2006. Morphological and genetic analysis were performed to identify the isolate. Also, the pathogenicity was conducted to complete $K\ddot{o}ch^{\prime}s$ postulate and compare susceptibility among chestnut cultivars. The molecular analysis between P. katsurae and P. hevae were performed with the isolates obtained from different countries including Korea or the sequences downloaded from Phytophthora webpage. The result showed that the isolated pathogen from chestnut was P. katsurae. There is no report of P. katsurae in Korea until now. P. katsurae was re-isolated from inoculated chestnut cultivars. Also, there was a slight difference in susceptibility among chestnut cultivars. The rDNA sequence of our isolate showed 100% similarity with sequence of the isolate cultured from Japan and New Zealand.

• Journal of Life Science
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• v.20 no.6
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• pp.819-824
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• 2010

Genus Phyllostachys is a long-lived woody species primarily distributed throughout South East Asia. Many species of this genus has been regarded as medically and ecologically important in the world. We evaluated representative samples of the four taxa with RAPD to estimate genetic relationships within the genus Phyllostachys. The percentages of polymorphic loci were 8.9-33.3% at the species level. P. bambusoides was found to show lower genetic diversity (H=0.018) than other species. Total genetic diversity ($H_T$) was 0.315, genetic diversity within populations ($H_S$) was 0.043, the proportion of total genetic diversity partitioned among populations ($G_{ST}$) was 0.659 and the gene flow (Nm) was 0.0263. As some Korean populations were isolated and patchily distributed, they exhibited low levels of genetic diversity. The four taxa of the genus Phyllostachys analyzed were distinctly related to a monophyletic. P. nigra var. henonis. Stapf was found to be more closely related to P. pubescens than to P. nigra. P. bambusoides was quite distinct from the remaining species.

• The Korean Journal of Mycology
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• v.43 no.4
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• pp.216-223
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• 2015

Amanita subgenus Lepidella is a well-known group that includes lethal amanitas. However, the taxonomic investigation of Korean Amanita species is still in progress. In this study, we collected Amanita specimens in Korea from 2009 to 2015 and classified 22 of them as subgenus Lepidella based on the morphology. Phylogenetic analysis of the 22 Amanita specimens based on the internal transcribed spacers sequences identified 16 phylogenetic species which included three undescribed Amanita species (A. sepiacea, A. modesta and A. kotohiraensis). Microscopic features of newly recorded Amanita species were photographed and line drawings were made. All collections cited here are deposited in the Herbarium Conservation Center of the National Institute of Agricultural Sciences.

• Korean Journal of Plant Resources
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• v.17 no.2
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• pp.116-121
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• 2004

Panax ginseng discarded and lower than 4th grade is caused by red skin disease showing red color skin in ginseng. This kind of red skin ginseng is found a lot in Panax ginseng rather than Panax quinquefolium, and it is considered that red skin disease might be caused by gene. Therefore, this study was carried out to detect genes resistant to red skin disease using RT-PCR. RNA was extracted from three years old ginseng root of both red skin and normal portion in the same root. After RNA extraction, PCR amplification was performed from cDNA using many random primers. As a result, specific band for red skin was found. It is considered that the gene forming band has possibility to be related with red skin disease, and this gene should be decided if it's related with red skin disease. If that gene is related with red skin disease, it will be used for transformation to foster for resistance to red skin disease as well as for selection marker. Bowever, if it's not related with red skin disease, more primers should be used to find gene related with red skin disease.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.430-434
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• 2009

Bacterial 16S rRNA gene sequences have been widely used for the studies on molecular phylogeny, evolutional history, and molecular detections. Bacterial genomes have multiple rRNA operons, of which gene sequences sometimes are variable. In the present study, heterogeneity of the Vibrio 16S rRNA gene sequences were investigated. Vibrio 16S rRNA sequences were obtained from GenBank databases, considering the completion of gene annotation of Vibrio genome sequences. These included V. cholerae, V. harveyi, V. parahaemolyticus, V. splendidus, and V. vulnificus. Chromosome 1 of the studied Vibrio had 7~10 copies of the 16S rRNA gene, and their intragenomic variations were less than 0.9% dissimilarity (more than 99.1% DNA similarity). Chromosome 2 had none or single 16S rRNA gene. Intragenomic 16S rRNA genotypes were detected at least 5 types (V. vulnificus #CMCP6) to 8 types (V. parahaemolyticus #RIMD 2210633, V. harveyi #ATCC BAA-1116). These suggest that Vibrio has high heterogeneity of the 16S rRNA gene sequences.

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.309-315
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• 2017

Most of acidophiles are found in the various low pH environments and affect to metal cycle through oxidation and reduction reactions. The present study was carried out above 50 strains as acidophiles isolated from acidic soils of exhausted mine and Jeju Gotjawal. Finally, total 19 strains obtained and were tentatively identified based on comparative similarity analysis for 16S rRNA gene sequence and physiological characterizations. These isolates belonged to Gammaproteobacteria (6 strains), Actinobacteria (5 strains), Betaproteobacteria (4 strains), Alphaproteobacteria (2 strains), and Bacilli (2 strains). We observed that these isolates can grow under low pH culture condition. This case study for analysis physiological characterizations of indigenous microorganisms in acidic soil might provide basic information on useful application.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.67-67
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• 2019

뽕나무과(Moraceae) 닥나무속(Broussonetia)의 품종에 대한 국내 연구동향으로는 잎의 성상이나 암꽃의 포길이, 엽신의 폭과 같은 수목학 분수학적 관점으로 특징을 파악하기 때문에 구분이 어려운 실정이다. 또한 닥나무(Broussonetia kazinoki Siebold)와 꾸지나무[Broussonetia papyrifera (L.) $L^{\prime}H{\acute{e}}r.$ ex Vent.]의 수목학적 특징이 유사하여 오동정의 사례가 발생하기도 한다. 닥나무의 향명은 다양하게 불리지만 그 분류기준은 명확하지 않다. 본 연구에서는 총 4개 마커(ITS, matK, trnL-F, ndhF)의 염기서열 분석과 분자계통학적 분류를 통해 닥나무와 꾸지나무의 교잡종으로 확인된 전라도지역 닥나무 8개체에 대하여 펄프제지 자원으로써의 특성을 확인하였다. 8개체 인피섬유의 형태학적 특징인 섬유장, 섬유폭, 섬유 내강(Lumen)폭을 통해 Runkel ratio, Slenderness ratio, Flexibility coefficient, Rigidity coefficient를 도출하고 종이의 기계적 강도, 내절도와의 상관관계, 섬유와 섬유간의 결합력 등을 예측하였다. 상기와 같은 연구결과는 유전형질이 동일한 전라도지역 닥나무의 형태학적 특성을 통해 펄프제지 공정에 영향을 미칠 수 있는 인자들을 분석 하였다. 이러한 특성에 따라 다양한 품질의 종이를 제조 할 수 있는 기초 자료로 제공될 것이다.

• The Korean Journal of Mycology
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• v.43 no.3
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• pp.200-205
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• 2015

Perilla frutescens var. japonica Hara was collected from farmland in Seongju-gun. Fifteen endophytic fungal strains with different colony morphologies were isolated from roots of P. frutescens. Waito-c rice seedlings were treated with the concentrated culture filtrates (CF) of endophytic fungi for observation of their plant growth-promoting activities. In the results, the CF of Y2H001 fungal strain promoted the growth of the waito-c rice seedlings. The phylogenetic tree of Y2H001 strain was analyzed by the combined sequences of the partial internal transcribed spacer region (ITS) and partial betatubulin gene. Molecular and morphological studies identified the Y2H001 strain as belonging to Aspergillus flavus. In gas chromatography mass spectrometry (GC/MS) analysis of the CF of Y2H001 strain, gibberellic acid (GA) was detected and quantified. Therefore, we describe Y2H001 strain as a new $GA_3$-producing A. flavus based on morphological, molecular characteristics and analysis of secondary metabolite.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5885-5892
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• 2014

Mangrove plants serve as a sink of heavy metals and contain phenolic compounds at a high level. Therefore, with mangrove plants, recent studies to develop phytoremediation and natural antioxidants have been conducted in the commercial and academic fields. In the present study, six mangroves in Weno Island of Micronesia were investigated for their phylogenetic relationship and antioxidant activities. First, to determine the phylogenetic relationship among them, rbcL (large subunit of ribulose-bisphosphate carboxylase), one of the chloroplast genes, was used as a molecular marker. According to the data, Xylocarpus, Sonneratia and Rhizophora showed close similarity but not Excoecaria. The levels of phenolic compounds in the bark were abundant in R. apiculata and X. granatum, accounting for 1.10 mM/mg, while R. stylosa and S. alba contained the low amounts, representing 0.73 mM/mg and 0.72 mM/mg, respectively (p<0.05). In addition, bark extracts from R. apiculata, X. granatum, X. moluccensis, and E. agallocha had high antioxidant activities through the DPPH radical scavenging activity and ABTS analysis, whereas S. alba showed the lowest activities. These results suggest that the bark of R. apiculata can be used as a good source for the development of natural antioxidants.