• Research in Plant Disease
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• v.12 no.3
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• pp.168-177
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• 2006

Thirty-nine strains of Colletotrichum gloeosporioides and 5 strains of C. acutatum stored in Korean Agricultural Culture Collection(KACC) were re-identified based on molecular characteristics of ribosomal internal transcribed spacer(ITS) and partial $\beta$-tubulin gene and cultural characteristics on potato dextrose agar(PDA) and Benomyl-added PDA. As the results, 19 strains were identified as C. acutatum with 13 strains of group A2, 5 strains of group A3, and 1 strain of group A4. In addition, 20 strains were identified as C. gloeosporioides with 18 strains of ribosomal DNA group(RG) 4 and 2 strains of RG6. The rest were identified as C. boninense RG5(2 strains), C. coccodes RG2(2 strains), and C. dematium RG12(1 strain). Out of domestic 31 strains, 12 strains were identified as C. acutatum A2, one strain as C. acutatum A3, 14 strains as C. gloeosporioides RG4, 2 strains as C. gloeosporioides RG6, one strains as C. boninense RG5 and one strain as C. dematium RG12. We also discussed taxonomy of C. gloeosporioides and C. acutatum and composition of C. gloeosporioides/C. acutatum isolates from major crops in Korea.

• Research in Plant Disease
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• v.24 no.1
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• pp.75-80
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• 2018

From 2014 to 2016, Fusarium wilt disease was found on fassionfruit in Iksan and Jeju, Korea. Symptoms included wilting of foliage, drying and withering of leaves, and stunting of the plants. The infected plants eventually died during growth. Colonies on potato dextrose agar were pinkish white, and felted with cottony and aerial mycelia with 35 mm after one week. Macroconidia were falcate to almost straight, thin-walled and usually 2-3 septate. Microconidia were usually formed on monophialides of the hyphae and were hyaline, smooth, oval to ellipsoidal, aseptate or medianly 1-septate, very occasionally 2-septate, slightly constricted at the septa, $3-12{\times}2.5-6{\mu}m$. On the basis of the morphological characteristics and phylogenetic analyses of two molecular markers, internal transcribed spacer rDNA and translation elongation factor $1{\alpha}$, the fungus was identified as Fusarium oxysporum. Pathogenicity of a representative isolate was proved by artificial inoculation, fulfilling Koch's postulates. To our knowledge, this is the first report on the occurrence of F. oxysporum on fassionfruit in Korea.

• Research in Plant Disease
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• v.23 no.1
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• pp.56-59
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• 2017

During growing season of 2011 to 2013, Sclerotinia rot symptoms consistently have been observed on basil in Yesan-gun, Chungcheongnam-do in Korea. The typical symptom formed initially brownish spot on leaf and stem, and then advancing margins, wilting the whole plant and blighting, eventually died. On the surface of diseased lesions was observed cottony, white, dense mat of mycelial growth, and sclerotia ($30-100{\mu}m$ diameter) formed on stem and leaf. Morphological and cultural characteristic on potato dextrose agar, color of colony was white and colorless chocolate, sclerotium of irregular shape of the oval was black and $5-50{\mu}m$ diameter in size. In pathogenicity test, necrosis and wilt of the inoculated stem were observed in all plants and the pathogen was reisolated from stems. On the basis of mycological characteristics, pathogenicity, and internal transcribed spacer rDNA sequence analysis, this fungus was identified as Sclerotinia sclerotiorum. This is the first report of Sclerotinia rot on basil caused by S. sclerotiorum in Korea.

• Parasites, Hosts and Diseases
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• v.53 no.4
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• pp.395-402
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• 2015

Non-human primates (NHPs) are confirmed as reservoirs of Cryptosporidium spp., Giardia intestinalis, and Enterocytozoon bieneusi. In this study, 197 fresh fecal samples from 8 NHP species in Qinling Mountains, northwestern China, were collected and examined using multilocus sequence typing (MLST) method. The results showed that 35 (17.8%) samples were positive for tested parasites, including Cryptosporidium spp. (3.0%), G. intestinalis (2.0%), and E. bieneusi (12.7%). Cryptosporidium spp. were detected in 6 fecal samples of Macaca mulatta, and were identified as C. parvum (n=1) and C. andersoni (n=5). Subtyping analysis showed Cryptosporidium spp. belonged to the C. andersoni MLST subtype (A4, A4, A4, and A1) and C. parvum 60 kDa glycoprotein (gp60) subtype IId A15G2R1. G. intestinalis assemblage E was detected in 3 M. mulatta and 1 Saimiri sciureus. Intra-variations were observed at the triose phosphate isomerase (tpi), beta giardin (bg), and glutamate dehydrogenase (gdh) loci, with 3, 1, and 2 new subtypes found in respective locus. E. bieneusi was found in Cercopithecus neglectus (25.0%), Papio hamadrayas (16.7%), M. mulatta (16.3%), S. sciureus (10%), and Rhinopithecus roxellana (9.5%), with 5 ribosomal internal transcribed spacer (ITS) genotypes: 2 known genotypes (D and BEB6) and 3 novel genotypes (MH, XH, and BSH). These findings indicated the presence of zoonotic potential of Cryptosporidium spp. and E. bieneusi in NHPs in Qinling Mountains. This is the first report of C. andersoni in NHPs. The present study provided basic information for control of cryptosporidiosis, giardiasis, and microsporidiosis in human and animals in this area.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.740-747
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• 2013

Leaf mold symptoms were found on commercial tomato cultivars carrying the Cf-9, a resistance gene to leaf mold pathogen Fulvia fulva in 2012 at Buyeo, Chungnam in Korea. Fifteen-fungal isolates were obtained from four Cf-9 cultivars of tomato including 'Cutie', 'otaerangdia', 'Unicorn' and 'Rapito'. Due to their same morphological appearances and colony color, nine isolates were selected and identified as F. fulva based on molecular analysis of the internal transcribed spacer rDNA sequence. Pathogenicity of the 15 isolates on five commercial cultivars carrying Cf-4, Cf-5, and Cf-9 were tested. All the isolates showed strong pathogenicity on Cf-9 cultivars, 'Cutie' and 'Dotaerangdia', and Cf-5 cultivar, 'Yoyocaptain'. In contrast, on Cf-4 cultivar, 'Superdotaerang', five isolates were virulent and the other isolates were not. In addition, two fungal isolates, infecting Cf-9 cultivar and non-infecting Cf-4 cultivar, were selected and their pathogenicity was tested on 17 commercial cultivars reported as tomato having Cf-9 resistance gene. Among them, 15 cultivars were susceptible and 2 cultivars were resistant. It is likely that the two cultivars include other resistance gene. To our knowledge, this is the first report on the occurrence of Cf-9 infecting F. fulfva strains in Korea.

• Journal of Life Science
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• v.26 no.12
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• pp.1446-1457
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• 2016

Wetlands exhibit intermediate characteristics of both terrestrial and aquatic ecosystems, and the biodiversity is rich in these unique biological habitats. The symbiotic relationships between plants and fungi that inhabit these wetlands play an important role in natural resource management, biodiversity, and conservation. Accordingly, the mujechi, having academic value for the study of the natural environment, was investigated in terms of genetic diversity of endophytic fungi, which inhabit the roots of wild plants. The internal transcribed spacer (ITS) region was amplified to identify fungal strains. In total, 226 strains were isolated and categorized into three phyla, seven classes, 10 orders, 22 families, and 31 genera. In plants by endophytic fungi were classified in Isachne globosa (Ig) to 19 genera, Scirpus karuisawensis (Sk) to 11 genera, Utricularia racemosa (Ur) to 19 genera, and one incertae sedis, Eriocaulon decemflorum (Ed) to 11 genera. The fungal taxa was identified the genera Acephala (19.9%), Tolypocladium (16.3%), Neopestalotiopsis (11.5%), and Perenniporia (7.1%). The fungal group isolated from Isachne globosa (Ig) grew the largest number of isolated fungal strains. After comprehensive evaluation, the endophytic fungal group from Utricularia racemosa (Ur) ranked highest in diversity analyses. From the roots of wild plant in mujechi-neup, it confirmed the distribution and diversity of endophytic fungi. This study provides the basic data to understand fungal community structure in peat wetlands.

• Journal of Veterinary Clinics
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• v.30 no.3
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• pp.218-221
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• 2013

A flightless brown hawk owl (Ninox scutulata) weighing 180 g was rescued and referred to the teaching veterinary hospital with humerus open fracture. On physical examination and radiography, open fracture of the left humerus was found. After 3 days, orthopedic surgery was operated with intramedullary pins and wires. The bird died 2 days after surgery with anorexia. On necropsy, multiple green nodules with 2-3 mm in diameter were observed at the surface and inside of the left lung. Numerous conidial heads and spores were seen in the center of foci in the histopathological examination. The mycelia penetrated the surrounding pulmonary parenchyma, showing inflammation and necrosis. The fungus was isolated from the lung and cultured on Sabouraud Dextrose Agar at $30^{\circ}C$ for 7 days. The colony was blue-green color with a powdery surface. The fungus was identified as Aspergillus fumigatus by DNA analysis, including the internal transcribed spacer region, partial ${\beta}$-tubulin, and the calmodulin gene. This case was diagnosed as pulmonary aspergillosis secondary to open fracture of pneumatic bone in a brown hawk owl.

• Journal of Microbiology and Biotechnology
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• v.23 no.7
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• pp.905-912
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• 2013

A novel species, Metschnikowia cibodasensis, is proposed to accommodate eight strains (ID03-$0093^T$, ID03-0094, ID03-0095, ID03-0096, ID03-0097, ID03-0098, ID03-0099, and ID03-0109) isolated from flowers of Saurauia pendula, Berberis nepalensis, and Brunfelsia americana in Cibodas Botanical Garden, West Java, Indonesia. The type strain of M. cibodasensis is ID03-$0093^T$ (= NBRC $101693^T$ =UICC $Y-335^T$ = BTCC-$Y25^T$). The common features of M. cibodasensis are a spherical to ellipsoidopedunculate shaped ascus, which contains one or two needle-shaped ascospores, and lyse at maturity. Asci generally develop directly from vegetative cells but sometimes from chlamydospores. The neighbor-joining tree based on the D1/D2 domain of nuclear large subunit (nLSU) ribosomal DNA sequences strongly supports that M. cibodasensis (eight strains) and its closest teleomorphic species, M. reukaufii, are different species by a 100% bootstrap value. The type strain of M. cibodasensis, ID03-$0093^T$, differed from M. reukaufii NBRC $1679^T$ by six nt (five substitutions and one deletion) in their D1/D2 region of nLSU rDNA, and by 18 nt (five deletions, four insertions, and nine substitutions) in their internal transcribed spacer regions of rDNA, respectively. Four strains representative of M. cibodasensis (ID03-$0093^T$, ID03-0095, ID03-0096, and ID03-0099) showed a mol% G+C content of $44.05{\pm}0.25%$, whereas that of M. reukaufii NBRC $1679^T$ was 41.3%. The low value of DNA-DNA homology (5-16%) in four strains of M. cibodasensis and M. reukaufii NBRC $1679^T$ strongly supported that these strains represent a distinct species.

• The Korean Journal of Mycology
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• v.46 no.2
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• pp.193-199
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• 2018

The fungus, Podosphaera pannosa, was identified in 1991 as the cause of powdery mildew symptoms on peach (Prunus persica var. persica) fruit from Korea based on the morphological characteristics of the conidial state. Recently, however, in Serbia and France, the cause of 'rusty spot' found on peach fruit was identified as P. leucotricha, and the cause of 'powdery mildew' on nectarine (Prunus persica var. nucipersica) fruit was identified as P. pannosa. To confirm the identity of the Korean pathogen, we collected four samples of powdery mildew from Korean peach fruit: three with the 'powdery mildew' symptom and one with the 'rusty spot' symptom. Morphological examination of the four samples confirmed P. pannosa as the pathogen. Internal transcribed spacer sequences of rDNA were analyzed for molecular characterization. A phylogenetic tree showed that the Korean isolates were clustered into a clade containing P. pannosa from Rosa species, with high sequence similarities of more than 99%. Thus, we showed that the powdery mildew and rusty spot symptoms on peach fruits from Korea are associated with P. pannosa.

• Mycobiology
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• v.45 no.4
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• pp.297-311
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• 2017

Saprolegniasis is one of the most devastating oomycete diseases in freshwater fish which is caused by species in the genus Saprolegnia including Saprolegnia parasitica. In this study, we isolated the strain of S. parasitica from diseased rainbow trout in Korea. Morphological and molecular based identification confirmed that isolated oomycete belongs to the member of S. parasitica, supported by its typical features including cotton-like mycelium, zoospores and phylogenetic analysis with internal transcribed spacer region. Pathogenicity of isolated S. parasitica was developed in embryo, juvenile, and adult zebrafish as a disease model. Host-pathogen interaction in adult zebrafish was investigated at transcriptional level. Upon infection with S. parasitica, pathogen/antigen recognition and signaling (TLR2, TLR4b, TLR5b, NOD1, and major histocompatibility complex class I), pro/anti-inflammatory cytokines (interleukin $[IL]-1{\beta}$, tumor necrosis factor ${\alpha}$, IL-6, IL-8, interferon ${\gamma}$, IL-12, and IL-10), matrix metalloproteinase (MMP9 and MMP13), cell surface molecules ($CD8^+$ and $CD4^+$) and antioxidant enzymes (superoxide dismutase, catalase) related genes were differentially modulated at 3- and 12-hr post infection. As an anti-Saprolegnia agent, plant based lawsone was applied to investigate on the susceptibility of S. parasitica showing the minimum inhibitory concentration and percentage inhibition of radial growth as $200{\mu}g/mL$ and 31.8%, respectively. Moreover, natural lawsone changed the membrane permeability of S. parasitica mycelium and caused irreversible damage and disintegration to the cellular membranes of S. parasitica. Transcriptional responses of the genes of S. parasitica mycelium exposed to lawsone were altered, indicating that lawsone could be a potential anti-S. parasitica agent for controlling S. parasitica infection.