• Journal of fish pathology
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• v.23 no.2
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• pp.145-153
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• 2010

Prevalence of a protozoan parasite Perkinsus olseni in Manila clam Ruditapes philippinarum was surveyed from July to December 2009 on the west and south coast of Korea. P. olseni infection was diagnosed using two primer sets, P.olseni NTS Forward/P.olseni NTS Reverse set and PolsITS-140F/PolsITS-600R set in polymerase chain reaction(PCR). The results using PolsITS-140F and PolsITS-600R primer set was retained up to 60% at all stations from July to December, except for Padori. Especially, Goheung showed 100% prevalence from October to December. The results about comparison of the 4 station's DNA sequences which were analyzed from PCR products(457bp) using PolsITS-140F and PolsITS-600R primer set, there were only 2base differences at Sunjedo.

• Mycobiology
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• v.38 no.4
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• pp.336-338
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• 2010

Rhizopus oryzae is reported for the first time on Cucumis melo L. var. makuwa Makino. A detailed description of this Korean specimen is given, along with its rDNA internal transcribed spacer sequence. On the basis of mycological characteristics and molecular data, the fungus was identified as R. oryzae Went & Prinsen Geerligs.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.252-254
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• 2001

A great deal of effort has been put into the identification of Alexandrium tamarense/fundyense/catenella complex by understanding correlation between morphological and subcellular characteristics. To date, the most promising tool for the study of these species is sequence analyses of rRNA genes that have been useful for various organisms' taxonomy and phylogeny, and its application such as in situ hybridization. (omitted)

• The Korean Journal of Mycology
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• v.41 no.1
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• pp.9-13
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• 2013

In this study, roots of Epipactis thunbergii were collected from Chujado on the north of Jeju-do. Six fungal isolates were isolated from surface-sterilized roots of the orchid and classified with groups based on morphological characteristics. Fungal DNA was extracted from each isolate and amplified ITS region using ITS1-OF/ITS4-OF primer pair. Three species of orchid mycorrhizal fungi were identified as Tulasnella calospora, Tulasnella sp. and Sebacina sp. based on molecular and morphological characteristics.

• Journal of Ginseng Research
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• v.43 no.1
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• pp.1-9
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• 2019

Background: Korean ginseng is an important cash crop in Asian countries. However, plant yield is reduced by pathogens. Among the Ilyonectria radicicola-species complex, I. mors-panacis is responsible for root-rot and replant failure of ginseng in Asia. The development of new methods to reveal the existence of the pathogen before cultivation is started is essential. Therefore, a quantitative real-time polymerase chain reaction method was developed to detect and quantify the pathogen in ginseng soils. Methods: In this study, a species-specific histone H3 primer set was developed for the quantification of I. mors-panacis. The primer set was used on DNA from other microbes to evaluate its sensitivity and selectivity for I. mors-panacis DNA. Sterilized soil samples artificially infected with the pathogen at different concentrations were used to evaluate the ability of the primer set to detect the pathogen population in the soil DNA. Finally, the pathogen was quantified in many natural soil samples. Results: The designed primer set was found to be sensitive and selective for I. mors-panacis DNA. In artificially infected sterilized soil samples, using quantitative real-time polymerase chain reaction the estimated amount of template was positively correlated with the pathogen concentration in soil samples ($R^2=0.95$), disease severity index ($R^2=0.99$), and colony-forming units ($R^2=0.87$). In natural soils, the pathogen was recorded in most fields producing bad yields at a range of $5.82{\pm}2.35pg/g$ to $892.34{\pm}103.70pg/g$ of soil. Conclusion: According to these results, the proposed primer set is applicable for estimating soil quality before ginseng cultivation. This will contribute to disease management and crop protection in the future.

• Journal of Marine Bioscience and Biotechnology
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• v.7 no.1
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• pp.11-18
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• 2015

An extracellular alkaline ${\alpha}$-D-mannosidase produced by a strain named as MA-01 was produced and its preliminary enzyme activity was characterized. Upon determining the 16S rDNA sequence and its homology search, the strain was identified to be one of species of the Bacillus safensis. Localization of enzyme was elucidated that ${\alpha}$-D-mannosidase can be found in culture medium as an extracellular enzyme. In addition, partial enzyme activity of 63% compared with the extracellular enzyme activity was observed in membrane protein. The optimal pH and temperature of the ${\alpha}$-D-mannosidase were pH 7.5 and $37^{\circ}C$, respectively. The $K_m$ and $V_{max}$ values of the ${\alpha}$-D-mannosidase in crude enzyme toward p-nitrophenyl-${\alpha}$-D-mannopyranoside were determined to be $455.6{\mu}M$ and $10.8{\mu}mole/min/mg$ of protein, respectively. To the best of our knowledge, this is the first report described the alkaline ${\alpha}$-D-mannosidase from the family of B. safensis.

• Korean Journal of Microbiology
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• v.39 no.2
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• pp.102-107
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• 2003

With the enrichment culture technique, bacterial strains which degrade diesel oil were isolated from soil contaminated with diesel oil. One of the isolates named GENECO 1 showed the highest activity for emulsification of diesel oil as well as the highest growth rate. This strain, GENECO 1, was identified as a Pseudomonas sp. based on its biochemical, physiological characteristics and 16S rDNA sequences. The optimal cultural conditions for cell growth and oil emulsifying activity of its culture were as follow; $30^{\circ}C$ for temperature, 7.0 for pH. Diesel oil degradation was analysed by the gas chromatography. More than 95% of 1% treated diesel oil were converted into a form no longer extractable by mixed organic solvents after 96 hours incubation.

• Research in Plant Disease
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• v.11 no.2
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• pp.135-139
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• 2005

Bacterial canker of Japanese apricot (Prunus mume Sieb. et Zucc.) was found in all orchards located at southern area of Korea. Typical symptoms were characterized by dark spots formed on fruits, brown lesions on leaves, and bacterial exudate oozed out of the cracked bark of diseased tree. Thirty-eight isolates from 16 different areas were identified on the basis of biochemical and physiological characteristics (LOPAT and GATTa test) and also on the basis of 165 rDNA and ITS sequences. Pathogenicity tests confirmed that bacterial canker of Japanese apricot in Korea is caused by Pseudomonas syringae pv. morsprunorum.

• The Korean Journal of Mycology
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• v.40 no.3
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• pp.136-140
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• 2012

Leaves of Lindera obtusiloba were collected from four sites in Gangwon Province, Korea. Endophytic fungi were isolated from the leaves and identified using ITS sequences of rDNA. Total twelve species belonging of endophytic fungi were identified; Alternaria alternata, Annulohypoxylon annulatum, Creosphaeria sassafras, Diaporthe eres, Discosia sp., Epicoccum nigrum, Glomerella acutata, Glomerella cingulata, Paraconiothyrium brasiliense, Pestalotiopsis neglecta, Phomopsis amygdali, Xylaria sp. The endophytic fungus, Phomopsis amygdali, was the most dominant species isolated from L. obtusiloba in this study and the fungal diversities varied in the different sites.

• Mycobiology
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• v.46 no.3
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• pp.192-204
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• 2018

The name Golovinomyces cynoglossi s. lat. is traditionally applied to a complex of morphologically similar powdery mildews on hosts of the plant family Boraginaceae. The current species-level taxonomy within this complex is ambiguous due to the lack of phylogenetic examinations. The present study applied phylogenetic methods to clarify the taxonomy of G. cynoglossi s. lat. Phylogenetic analysis of rDNA ITS sequences retrieved from Asian, European and North American specimens revealed that G. cynoglossi s. lat. collections from different hosts involved several species in five clearly separated lineages. Clade I consists primarily of Golovinomyces cynoglossi s. str. on Cynoglossum. Clade III consists of Golovinomyces sequences retrieved from the host genera Symphytum and Pulmonaria. The taxa within clade III are now assigned to G. asperifoliorum comb. nov. Clade V encompasses G. cynoglossi s. lat. on the host genera Bothriospermum, Buglossoides, Echium, Myosotis, and Trigonotis. The taxa within clade V are now assigned to G. asperifolii comb. nov. The species concerned in this study were lecto- and epitypified to stabilize their nomenclature.