• 식물병연구
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• 제29권3호
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• pp.299-303
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• 2023

Rust symptoms on Meliosma myriantha trees have been noticed during disease surveys in Korea since 2010, with a high disease incidence frequently surpassing 90%. The causal fungus of the rust disease was identified as Neophysopella vitis based on the morphological investigation and molecular sequence analysis of the internal transcribed spacer (ITS) and large subunit (LSU) rDNA regions. This is the first report of rust disease caused by N. vitis on M. myriantha in Korea. A pathogenicity assay proved that M. myriantha serves as the aecial host of N. vitis as spermogonia and aeciospores were produced, which can infect the two uredinial hosts, Boston ivy (Parthenocissus tricuspidata) and Virginia creeper (Parthenocissus quinquefolia).

• 한국균학회지
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• 제51권2호
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• pp.91-100
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• 2023

During an investigation of micro-fungi in soil, two fungal isolates belonging to the phylum Ascomycota, namely KNUF-20-NI011 and KNUF-20-NI006, were collected from Gyeongbuk Province and Dokdo Island in Korea and identified as Clonostachys divergens and Chrysosporium merdarium, respectively. The fungal isolates were confirmed through molecular phylogenetic analyses of the internal transcribed spacer regions, 28S rDNA large subunit, and β-tubulin sequences. Cultural and morphological characteristics were observed and determined using different media. These species were identified based on phylogenetic relationships along with their cultural and morphological characteristics. To our knowledge, this is the first report on Clonostachys divergens and Chrysosporium merdarium in Korea.

• 한국균학회지
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• 제50권3호
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• pp.243-248
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• 2022

In Japan and China, Podosphaera pseudofusca causes powdery mildew in Fatoua villosa. During a taxonomic revision of Korean powdery mildew fungi, isolates newly collected from F. villosa were studied. Through morphological examination and molecular phylogenetic analyses of the internal transcribed spacer region and large subunit gene of rDNA, the powdery mildew fungus was identified as Podosphaera xanthii. In this study, we propose the merging of P. pseudofusca sensu Braun into the P. xanthii complex. To the best of our knowledge, this is the first report of Podosphaera powdery mildew on F. villosa in Korea.

• 한국균학회지
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• 제50권1호
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• pp.55-59
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• 2022

Anamorph of a powdery mildew was collected from Convolvulus arvensis (Convolvulaceae) in 2021 in Korea. Based on the morphological examination and molecular phylogenetic analyses of the internal transcribed spacer and large subunit rDNA gene, the powdery mildew was identified as Erysiphe convolvuli. This powdery mildew species is commonly found in Europe and North America, but rarely in East Asia. The holomorph of this powdery mildew was first recorded on Calystegia hederacea in Korea. Conclusively, this is the first report of E. convolvuli on C. arvensis and the second record of this powdery mildew species in Korea.

• 한국균학회지
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• 제50권2호
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• pp.125-130
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• 2022

The powdery mildew found on Magnolia kobus was recorded as Microsphaera alni for the first time in Korea in 1975. After splitting M. alni into several distinct species, this mildew was regarded as Microsphaera magnifica, now Erysiphe magnifica. Since E. magnifica is known to be a North American species, the powdery mildew found on M. kobus in Korea was studied to clarify its identity. Based on morphological characteristics and sequencing results of the internal transcribed spacer and large subunit rDNA gene, the powdery mildew found on M. kobus in Korea was identified as Erysiphe magnoliicola.

• 한국균학회지
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• 제50권3호
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• pp.173-181
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• 2022

Endophytic fungi were isolated from needle leaves of two conifer species in Korea. The fungal isolates were identified based on their morphological characteristics and phylogenetic analyses of their internal transcribed spacer and large-subunit rDNA regions. Three species of endophytic fungi, namely Celosporium laricicola, Neocatenulostroma germanicum, and Phaeophleospora eucalypticola were the first records in Korea. In this study, we reported the morphological and phylogenetic characteristics of these fungi.

• ALGAE
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• 제33권1호
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• pp.21-35
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• 2018

The phototrophic dinoflagellate genus Scrippsiella is known to have a worldwide distribution. Here, we report for the first time, the occurrence of Scrippsiella lachrymosa in Korean waters. Unlike the other stains of S. lachrymosa whose cultures had been established from cysts in the sediments, the clonal culture of the Korean strain of S. lachrymosa was established from motile cells. When the sulcal plates of S. lachrymosa, which have not been fully described to date, were carefully examined using scanning electron microscopy, the Korean strain of S. lachrymosa clearly exhibited the anterior sulcal plate (s.a.), right sulcal plate (s.d.), left sulcal plate (s.s.), median sulcal plate (s.m.), and posterior sulcal plate (s.p.). When properly aligned, the large subunit (LSU) rDNA sequence of the Korean strain of S. lachrymosa was ca. 1% different from those of two Norwegian strains of S. lachrymosa, the only strains for which LSU sequences have been reported. The internal transcribed spacer (ITS) rDNA sequence of the Korean strain of S. lachrymosa was also ca. 1% different from those of the Scottish and Chinese strains and 3% different from those of the Canadian, German, Greek, and Portuguese strains. Thus, the Korean S. lachrymosa strain has unique LSU and ITS sequences. The abundances of S. lachrymosa in the waters of 28 stations, located in the East, West, and South Sea of Korea, were quantified in four seasons from January 2016 to October 2017, using quantitative real-time polymerase chain reaction method and newly designed specific primer-probe sets. Its abundances were >$0.1cells\;mL^{-1}$ at eight stations in January and March 2016 and March 2017, and its highest abundance in Korean waters was $26cells\;mL^{-1}$. Thus, S. lachrymosa has a nationwide distribution in Korean waters as motile cells.

• Mycobiology
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• 제48권6호
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• pp.450-463
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• 2020

The strains 17E-042, 17E-039, and NC13-171 belong to Ascomycota and were isolated from soil collected from Sancheong-gun and Yeongam-gun, Korea. The strain 17E-042 produced white mycelial colonies that developed a sienna color with a round margin on potato dextrose agar (PDA), and the reverse side developed a light sienna color. Morphologically, this strain was similar to the strains of Arthrinium phragmites and A. hydei, but the shorter conidial size of the newly identified strain (17E-042) was distinct. The strain 17E-039 produced macroconidia that were pale yellow to orange-brown, elongated-ellipsoid to oblong, round at both ends, primarily straight but sometimes slightly curved, 0-septate, thin-walled, and filled with numerous droplets, having diameters of 20.4-34.3 × 8.0-12.0 ㎛. And the strain NC13-171 formed hyaline to light brown chlamydospores, solitary or in a chain. Multigene phylogenetic analyses were conducted using sequence data obtained from internal transcribed spacer (ITS) regions, 28S rDNA large subunit (LSU), β-tubulin (TUB2), translation elongation factor 1-alpha (TEF1-α), and RNA polymerase II large subunit (RPB2) genes. The results of molecular phylogeny, the detailed descriptions and illustrations of each species strongly support our proposal that these strains from soil in Korea be designated as Arthrinium minutisporum sp. nov. and two new records of Pezicula neosporulosa and Acrocalymma pterocarpi.

• Mycobiology
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• 제51권3호
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• pp.115-121
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• 2023

The fungal strain KNUF-22-18B, belonging to Cucurbitariaceae, was discovered from a stink bug (Hygia lativentris) during the investigation of insect microbiota in Chungnam Province, South Korea. The colonies of the strain KNUF-22-18B were wooly floccose, white to brown in the center on oatmeal agar (OA), and the colonies were buff, margin even, and colorless, reverse white to yellowish toward the center on malt extract agar (MEA). The strain KNUF-22-18B produced pycnidia after 60 days of culturing on potato dextrose agar, but pycnidia were not observed on OA. On the contrary, N. keratinophila CBS 121759^T abundantly formed superficial pycnidia on OA and MEA after a few days. The strain KNUF-22-18B produced chlamydospores subglobose to globose, mainly in the chain, with a small diameter of 4.4-8.8 ㎛. At the same time, N. keratinophila CBS 121759^T displayed a globose terminal with a diameter of 8-10 ㎛. A multilocus phylogeny using the internal transcribed spacer regions, 28S rDNA large subunit, b-tubulin, and RNA polymerase II large subunit genes further validated the uniqueness of the strain. The detailed description and illustration of the proposed species as Neocucurbitaria chlamydospora sp. nov. from Korea was strongly supported by molecular phylogeny.

• Asian-Australasian Journal of Animal Sciences
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• 제14권6호
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• pp.880-884
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• 2001

Rumen microbiology research has undergone several evolutionary steps: the isolation and nutritional characterization of readily cultivated microbes; followed by the cloning and sequence analysis of individual genes relevant to key digestive processes; through to the use of small subunit ribosomal RNA (SSU rRNA) sequences for a cultivation-independent examination of microbial diversity. Our knowledge of rumen microbiology has expanded as a result, but the translation of this information into productive alterations of ruminal function has been rather limited. For instance, the cloning and characterization of cellulase genes in Escherichia coli has yielded some valuable information about this complex enzyme system in ruminal bacteria. SSU rRNA analyses have also confirmed that a considerable amount of the microbial diversity in the rumen is not represented in existing culture collections. However, we still have little idea of whether the key, and potentially rate-limiting, gene products and (or) microbial interactions have been identified. Technologies allowing high throughput nucleotide and protein sequence analysis have led to the emergence of two new fields of investigation, genomics and proteomics. Both disciplines can be further subdivided into functional and comparative lines of investigation. The massive accumulation of microbial DNA and protein sequence data, including complete genome sequences, is revolutionizing the way we examine microbial physiology and diversity. We describe here some examples of our use of genomics- and proteomics-based methods, to analyze the cellulase system of Ruminococcus flavefaciens FD-1 and explore the genome of Ruminococcus albus 8. At Illinois, we are using bacterial artificial chromosome (BAC) vectors to create libraries containing large (>75 kbases), contiguous segments of DNA from R. flavefaciens FD-1. Considering that every bacterium is not a candidate for whole genome sequencing, BAC libraries offer an attractive, alternative method to perform physical and functional analyses of a bacterium's genome. Our first plan is to use these BAC clones to determine whether or not cellulases and accessory genes in R. flavefaciens exist in clusters of orthologous genes (COGs). Proteomics is also being used to complement the BAC library/DNA sequencing approach. Proteins differentially expressed in response to carbon source are being identified by 2-D SDS-PAGE, followed by in-gel-digests and peptide mass mapping by MALDI-TOF Mass Spectrometry, as well as peptide sequencing by Edman degradation. At Ohio State, we have used a combination of functional proteomics, mutational analysis and differential display RT-PCR to obtain evidence suggesting that in addition to a cellulosome-like mechanism, R. albus 8 possesses other mechanisms for adhesion to plant surfaces. Genome walking on either side of these differentially expressed transcripts has also resulted in two interesting observations: i) a relatively large number of genes with no matches in the current databases and; ii) the identification of genes with a high level of sequence identity to those identified, until now, in the archaebacteria. Genomics and proteomics will also accelerate our understanding of microbial interactions, and allow a greater degree of in situ analyses in the future. The challenge is to utilize genomics and proteomics to improve our fundamental understanding of microbial physiology, diversity and ecology, and overcome constraints to ruminal function.