• Mycobiology
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• v.49 no.4
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• pp.385-395
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• 2021

Fungal endophytes have been recorded in various plant species with a richness of diversity, and their presence plays an essential role in host plant protection against biotic and abiotic stresses. This study applied the Illumina MiSeq sequencing platform based on the amplification of fungal ribosomal ITS2 region to analyze fungal endophytic communities of two oak species (Quercus mongolica and Q. serrata) with different oak wilt disease susceptibilities in Korea. The results showed a total of 230,768 sequencing reads were obtained and clustered at a 97% similarity threshold into 709 operational taxonomic units (OTUs). The OTUs of Q. serrata were higher than that of Q. mongolica with the number of 617 OTUs and 512 OTUs, respectively. Shannon index also showed that Q. serrata had a significantly higher level of fungal diversity than Q. mongolica. Total of OTUs were assigned into 5 fungal phyla, 17 classes, 60 orders, 133 families, 195 genera, and 280 species. Ascomycota was the dominant phylum with 75.11% relative abundance, followed by Basidiomycota with 5.28%. Leptosillia, Aureobasidium and Acanthostigma were the most abundant genera detected in Q. serrata with the average relative abundance of 2.85, 2.76, and 2.19%, respectively. On the other hand, Peltaster, Cladosporium and Monochaetia were the most common genera detected in Q. mongolica with the average relative abundance of 4.83, 3.03, and 2.87%, respectively. Our results indicated that fungal endophytic communities were significantly different between two oak species and these differences could influence responses of host trees to oak wilt disease caused by Raffaelea quercus-mongolicae.

• Mycobiology
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• v.45 no.3
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• pp.160-171
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• 2017

Larvae of Bradysia agrestis, an insect vector that transports plant pathogens, were sampled from geographically isolated regions in Korea to identify their cutaneous fungal and bacterial flora. Sampled areas were chosen within the distribution range of B. agrestis; each site was more than 91 km apart to ensure geographical segregation. We isolated 76 microbial (fungi and bacteria) strains (site 1, 29; site 2, 29; site 3, 18 strains) that were identified on the basis of morphological differences. Species identification was molecularly confirmed by determination of universal fungal internal transcribed spacer and bacterial 16S rRNA gene sequences in comparison to sequences in the EzTaxon database and the NCBI GenBank database, and their phylogenetic relationships were determined. The fungal isolates belonged to 2 phyla, 5 classes, and 7 genera; bacterial species belonged to 23 genera and 32 species. Microbial diversity differed significantly among the geographical groups with respect to Margalef's richness (3.9, 3.6, and 4.5), Menhinick's index (2.65, 2.46, and 3.30), Simpson's index (0.06, 0.12, and 0.01), and Shannon's index (2.50, 2.17, and 2.58). Although the microbial genera distribution or diversity values clearly varied among geographical groups, common genera were identified in all groups, including the fungal genus Cladosporium, and the bacterial genera Bacillus and Rhodococcus. According to classic principles of co-evolutionary relationship, these genera might have a closer association with their host insect vector B. agrestis than other genera identified. Some cutaneous bacterial genera (e.g., Pseudomonas) displaying weak interdependency with insect vectors may be hazardous to agricultural environments via mechanical transmission via B. agrestis. This study provides comprehensive information regarding the cutaneous microflora of B. agrestis, which can help in the control of such pests for crop management.

• Journal of Life Science
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• v.31 no.4
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• pp.377-384
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• 2021

Researching the soil fungal community is important to understand the interaction between fungi and living plants. However, too few studies have examined the soil fungal community and their interactions with plants. Rhododendron mucronulatum, commonly known as Korean rosebay, is an important forest resource that has aesthetic, ecological, and potential pharmacological values. We used a pyrosequencing method to analyze the characteristics of fungal communities from R. mucronulatum soil samples from Biseul mountain county park, which is one of the famous places for large R. mucronulatum colonies in South Korea. We collected soil core samples in February and August at three sites in the Biseul Mountain County Park, taking into consideration the regional and seasonal conditions. We obtained 454,157 validated reads after pyrosequencing all six samples. The fungal communities from the first observation spot in August had the richest species diversity among the samples. Basidiomycota, Ascomycota, and Mortierellomycota were major phyla in the samples. Agaricales_f, Mortierellaceae, and Clavariaceae were major families in the samples. The genus Mortierella was the most dominant in all six samples. Overall, 19 genera could be associated with R. mucronulatum. Sample 1 had 109 genera in sample 1, sample 2 had 111 genera, and sample 3 had 112 genera that were uniquely identified. The samples collected in August had 28 identified genera, that existed only in summer samples, indicating a weather effect. This study can be used as basic research to understand the relationship between soil fungi and plants.

• Mycobiology
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• v.35 no.2
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• pp.100-102
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• 2007

Pet dogs have been considered to be involved in the contamination of indoor air by serving as a source of providing molds at houses. Currently, information on the molds originated from pet dogs is rarely available in Korea. The present study was carried out to obtain basic information on the fungi present on pet dogs. For this, fungal isolation was performed to the skin and hairs of 70 pet dogs at different houses and veterinary hospitals. A total of 44 fungal isolates were obtained from skin (27 isolates) and hairs (17 isolates) of the dogs investigated. Based on the observation of microstructures and colony morphology, and the ITS rDNA sequence analysis, the fungal isolates were identified at the level of genus. The identified isolates belong to the genera of Alternaria, Aspergillus, Beauveria, Chrysosporium, Cladosporium, Penicillium, Scopulariopsis, and Trichoderma. Among these genera, Aspergillus (25%), Cladosporium (23%) and Penicillium (20.5%) were 3 major genera. 63% of the 44 isolates showed color changes on dermatophyte test medium (DTM). When we tested the growth ability of 44 isolates at $37^{\circ}C$, 45% of the isolates were able to grow. These results show that pet dogs could carry fungi having a potentiality of affecting on human health.

• Mycobiology
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• v.49 no.6
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• pp.559-581
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• 2021

The coastal marine ecosystems of Vietnam are one of the global biodiversity hotspots, but the biodiversity of marine fungi is not well known. To fill this major gap of knowledge, we assessed the genetic diversity (ITS sequence) of 75 fungal strains isolated from 11 surface coastal marine and deeper waters in Nha Trang Bay and Van Phong Bay using a culture-dependent approach and 5 OTUs (Operational Taxonomic Units) of fungi in three representative sampling sites using next-generation sequencing. The results from both approaches shared similar fungal taxonomy to the most abundant phylum (Ascomycota), genera (Candida and Aspergillus) and species (Candida blankii) but were different at less common taxa. Culturable fungal strains in this study belong to 3 phyla, 5 subdivisions, 7 classes, 12 orders, 17 families, 22 genera and at least 40 species, of which 29 species have been identified and several species are likely novel. Among identified species, 12 and 28 are new records in global and Vietnamese marine areas, respectively. The analysis of enzyme activity and the checklist of trophic mode and guild assignment provided valuable additional biological information and suggested the ecological function of planktonic fungi in the marine food web. This is the largest dataset of marine fungal biodiversity on morphology, phylogeny and enzyme activity in the tropical coastal ecosystems of Vietnam and Southeast Asia. Biogeographic aspects, ecological factors and human impact may structure mycoplankton communities in such aquatic habitats.

• Mycobiology
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• v.30 no.3
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• pp.170-174
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• 2002

A total of twenty-nine species and one species variety belonging to 12 genera was isolated from 30 samples of molasses on 1% glucose(10 genera, 22 species and 1 variety) and 50% sucrose(7, 21 and 1) Czapek's agar at $25^{\circ}C$ media. Aspergillus, Mucor, Mycosphaerella and Penicillium were the most common genera on the two types of media. From the above genera, the most prevalent species were: Aspergillus flavus, A. fumigatus, A. niger, Mycosphaerella tassiana, Penicillium chrysogenum, P. oxalicum and P. purpurogenum. Also, some species were only isolated on 50% sucrose such as Eurotium amstelodami, E. chevalieri, E. repens, Humicola fuscoatra, Penicillium aurantiogriseum and P. puberulum. About 65 fungal isolates isolated from 50% sucrose agar were tested for their ability to produce invertase enzyme in liquid medium and 93.8% of the isolates could produce this enzyme. From the positive isolates, 32 showed high invertase activity, 21 had moderate activity and the remaining 8 isolates were of weak activity. Sixty isolates of Aspergillus, Emericella, Eurotium, Mycosphaerella and Penicillium from the preceding study were screened for the presence of their respective mycotoxins. Larva of brine shrimp(Artema sauna L.) were used for toxicity test of the fungal crude extracts. Three isolates out of 60 tested were toxic. Using thin-layer chromatographic technique, 5 different known mycotoxin were detected aflatoxins : B1, B2, G1, G2 and citrinin.

• Mycobiology
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• v.35 no.3
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• pp.159-161
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• 2007

Pine tree death caused by pine wood nematode(PWN) involves phoretic relationships between PWN and its vector Japanese pine sawyer beetle(JPS). In an effort to understand the diversity of fungi involved in PWN life cycle, a total of 176 fungal isolates were collected from PWNs, adults and larvae of JPS, PWN-diseased Japanese black pine that was cut down in 2005 at Jinju, Korea. Based on microscopic observation and colony morphology, and sequence analysis of the ITS rDNA, the fungal isolates were identified at the level of genus. Three genera including Mucor, Ophiostoma, and Penicillium were identified from PWN. Two genera of Ophiostoma and Penicillium were discovered from JPS larvae. Frpm JPS adult beetles, nine genera of Aspergillus, Gibberalla, Hypocrea, Irpex, Leptosphaeria, Ophiostoma, Penicillium, and Plectosphaerella and unknown basidio-mycetes were found. Ten genera from PWN-infected weed were confirmed as Bionectria, Botrytis, Camarops, Fusarium, Hypocrea, Nectria, Mucor, Ophiostoma, Penicillium, and Trichoderma. Penicillium and Ophiostoma were commonly distributed on PWN and its vector and host. This is first report of the fungi associated with PWN and its vector and host in Korea.

• The Plant Pathology Journal
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• v.34 no.5
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• pp.356-366
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• 2018

The red flour beetle, Tribolium castaneum, is one of the most common and economically important pests of stored cereal products worldwide. Furthermore, these beetles can act as vectors for several fungal post-harvest diseases. In this study, we collected T. castaneum from 49 rice processing complexes (RPCs) nationwide during 2016-2017 and identified contaminating fungal species on the surface of the beetles. Five beetles from each region were placed on potato dextrose agar media or Fusarium selection media after wet processing with 100% relative humidity at $27^{\circ}C$ for one week. A total of 142 fungal isolates were thus collected. By sequence analysis of the internal transcribed spacer region, 23 fungal genera including one unidentified taxon were found to be associated with T. castaneum. The genus Aspergillus spp. (28.9%) was the most frequently present, followed by Cladosporium spp. (12.0%), Hyphopichia burtonii (9.2%), Penicillium spp. (8.5%), Mucor spp. (6.3%), Rhizopus spp. (5.6%), Cephaliophora spp. (3.5%), Alternaria alternata (2.8%) and Monascus sp. (2.8%). Less commonly identified were genera Fusarium, Nigrospora, Beauveria, Chaetomium, Coprinellus, Irpex, Lichtheimia, Trichoderma, Byssochlamys, Cochliobolus, Cunninghamella, Mortierella, Polyporales, Rhizomucor and Talaromyces. Among the isolates, two known mycotoxin-producing fungi, Aspergillus flavus and Fusarium spp. were also identified. This result is consistent with previous studies that surveyed fungal and mycotoxin contamination in rice from RPCs. Our study indicates that the storage pest, T. castaneum, would play an important role in spreading fungal contaminants and consequently increasing mycotoxin contamination in stored rice.

• Journal of Plant Biology
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• v.20 no.1
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• pp.29-44
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• 1977

During a week from 6th August in 1976 to survey the fungal flora on higher fleshy fungi around Mt. Jogye 193 specimens were collected and then examined tentatively. As a result fo identification except several troublesome ones it was known that they lie within 66 genera, 110 species, 3 varieties, and 2 forms. Out of them five genera, Eutypa, Sarcosoma in Ascomycetes, and Corticium, Heimiella, Clitopilus in Basidiomycetes were confirmed as unrecorded genera to Korea. And therefrom 26 species and 1 form corresponding almost to the fourth of sum were identified as unrecorded species to Korea, among which Basidiomycetes are provided with descriptions and figures in this survey report.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.112-119
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• 1985

The 34 species of the ornamental plants belong to 19 families which seemed to be infected by fungal pathogens were collected at 6 localities in Korea. The diseases were diagnosed with their symptoms, the characteristics of the pathogens and the pathogenicity on host plants. The results were summarized as follows : The 37 diseases by 16 genera of fungal pathogens were investigated on 32 species of 32 genera of the ornamental plants. Among them 22 diseases by 11 genera of fungal pathogens were turned out to be new diseases which have not been described on the host plants of 19 species in Korea.