• The Plant Pathology Journal
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• v.31 no.3
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• pp.316-321
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• 2015

A small cationic peptide (JH8944) was tested for activity against a number of pathogens of agricultural crops. JH8944 inhibited conidium growth in most of the tested plant pathogens with a dose of $50{\mu}g/ml$, although one isolate of Fusarium oxysporum was inhibited at $5{\mu}g/ml$ of JH8944. Most conidia of Fusarium graminearum were killed within 6 hours of treatment with $50{\mu}g/ml$ of JH8944. Germinating F. graminearum conidia required $238{\mu}g/ml$ of JH8944 for 90% growth inhibition. The peptide did not cause any damage to tissues surrounding maize leaf punctures when tested at a higher concentration of $250{\mu}g/ml$ even after 3 days. Liposomes consisting of phosphatidylglycerol were susceptible to leakage after treatment with 25 and $50{\mu}g/ml$ of JH8944. These experiments suggest this peptide destroys fungal membrane integrity and could be utilized for control of crop fungal pathogens.

• The Korean Journal of Mycology
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• v.41 no.4
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• pp.287-291
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• 2013

Tremella fuciformis, as one of higher basidiomycetes, can asexually reproduce yeast-like conidium (YLC) cells by budding. We have developed an efficient method to introduce pCambia1300 plasmid containing hph gene into YLC cells using Agrobacterium. This was successful only when YLC cells were wounded by NaOH treatment before co-cultivation. In average, 40~50 transformants were produced out of $1.0{\times}10^6$ YLC cells investigated. The T-DNA transfer was confirmed by PCR. Methanolic extracts from transformants demonstrated different levels of toxicity against SKOV-3 cervical cancer cells.

• The Plant Pathology Journal
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• v.15 no.1
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• pp.72-75
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• 1999

A scab disease occurred on watermelon seedlings by the infection of Cladosporium cucumberinum. This is the first report demonstrating the scab disease on watermelon in Korea. The casual agent attacked all plant parts of the seedlings on the ground. Infection sites were initiated with sunken and dark green spots, and then suddenly developed to large lesions softened with gummy substances. When hypocotyl and leaf stalk of seedlings were infected and softened, upper parts of seedlings were brokin down, dried and eventually died. Conidiophores of the fungus were characterized by pale olivaceous brown color, and variable length of about 3-5 mm in width. Conidia were formed I long branched chains, and conidium was ellipsoidal, fusiform or subspherical single cell mostly without septum. Morphological characteristics of the fungus were almost identical to Cladosporium cucumerinum Ellis & Authur. The fungus was also pathogenic to cucumber, squash and oriental melon, suggesting that it is a common pathogen to cucurbits. However, the fungus was not pathogenic to bottle gourd.

• The Plant Pathology Journal
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• v.17 no.4
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• pp.216-221
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• 2001

Dieback of pine branches or twigs with brown needles occurs most commonly on Pinus species after severe winter in Korea. In this study, Cenangium ferruginosum was isolated from infected stems, branches, and twigs of Pinus koraiensis (C1), P. densiflora (C2), and P. thunbergii (C3). Morphological and cultural characteristics of the isolates were than compared. There were no significant differences in the morphological characteristics of conidia and ascospores produced by the three isolates. However, cultural differences were observed among the isolates. Optimum temperatures for mycelial growth of C1, C2, and C3 were 15, 20, and $20^{\circ}$, respectively. C1 produced a few conidia and no ascospores, while C2 and C3 produced abundant ascospores and conidia. While optimum temperatures for mycelial growth ranged from 15 to $20^{\circ}$, mycelial growth was also relatively good at lower temperatures of 5-$10^{\circ}$. Conidiomata and conidia were produced on MSA (malt extract soya peptone agar) after 25-30 days of incubation in the dark at $15^{\circ}$. Apothecia were produced by altering culture condition from 15 to $20^{\circ}$, and incubating for 35-60 more days. Optimum temperature for ascospore and conidium germination was $20^{\circ}$. RAPD analysis revealed that there was high similarity of 0.78 between C2 and C3, and low similarity of 0.31 between C2 or C3 and C1.

• Mycobiology
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• v.33 no.4
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• pp.194-199
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• 2005

Application of fertilizers such as urea, diammonium phosphate (DAP) and muriate of potash in soil adversely affected the spore germination of Arthrobotrys dactyloides. Amendment of soil with urea at the concentrations of 1.0%, 0.5% and 0.1 % completely inhibited spore germination and direct trap formation on the conidium, whereas muriate of potash delayed and reduced the spore germination even at the lowest concentration. DAP also inhibited spore germination at 1.0% concentration, while at lower concentration the percentage of spore germination was reduced. Application of neem cake at the concentration of 0.5% also inhibited spore germination after 24 h of amendment. The inhibitory effect of neem cake was reduced after 15 days of amendment, while after 30 days after amendment the inhibitory effect was completely lost and the spore germinated by direct trap as in unamended soil. Nematodes were not attracted to ungerminated spores after 24 h of amendment. After 15 days of amendment nematodes were attracted to agar blocks containing fewer germinated spores after 24 h of incubation but after 48 h of incubation large number of nematodes were attracted and trapped by the germinated spores with direct traps. After 30 days of amendment, larger number of nematodes were attracted and trapped by direct traps.

• Mycobiology
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• v.45 no.3
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• pp.220-225
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• 2017

Ginseng root rot caused by Cylindrocarpon destructans is the most destructive disease of ginseng. Six different fungicides (thiophanate-methyl, benomyl, prochloraz, mancozeb, azoxystrobin, and iprodione) were selected to evaluate the inhibitory effect on the mycelial growth and conidial germination of C. destructans isolates. Benomyl and prochloraz were found to be the most effective fungicides in inhibiting mycelial growth of all tested isolates, showing 64.7% to 100% inhibition at a concentration of $10{\mu}g/mL$, whereas thiophanate-methyl was the least effective fungicide, showing less than 50% inhibition even at a higher concentration of $100{\mu}g/mL$. The tested fungicides exhibited less than 20% inhibition of conidium germination at concentrations of 0.01, 0.1, and $1{\mu}g/mL$. However, the inhibition effect of mancozeb on condium germination of C. destructans was significantly increased to 92% to 99% at a higher concentration of $100{\mu}g/mL$, while the others still showed no higher than 30% inhibition.

• The Korean Journal of Mycology
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• v.19 no.1
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• pp.27-31
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• 1991

Formation of conidium, an asexual organ on the hyphae, was examined from ten species of Pleurotus. Conidiospores of them were distinguished into two types of spores; an elliptical and a globose spores. Dikaryotic hyphae of ten species and monokaryotic hyphae of three species were observed to produce conidiospore. Conidia were observed on the hyphae grown on mushroom complete agar medium but were not on mushroom minimal agar medium. Two aconidial mutants were obtained by the ultraviolet irradiation.

• The Korean Journal of Mycology
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• v.1 no.2
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• pp.31-33
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• 1973

On September 1972, a blight disease of turf (Arostis canina L.)was found in a golf link in Seoul Country Club at Seoul, Korea. Yellow circular patches of 15-20cm in diameter were observed and spreaded irregulary to collapse of themselves. The roots of the diseased plants were dark in color and were in a final state of decay. We isolated Curvularia sp. from the diseased plants and investigated the morphological and cultural characters. Its characters as follows: Mycelia septate, branched, hyaline or yellowish brown colored. Conidiophores septate, thin brown, unbranched. $65-270{\times}3.5-5{\mu}$. Conidia clustered at the tips of conidiophores, boat form or slightly curved with 1-5 septa, brown; both end cells hyaline; the third cell much larger than the others. $26.1-33.3{\times}9.5-10.1{\mu}$ (4 cell's conidium). The pathogenicity of the fungus to host plant was confirmed by soil inoculation method. We classified the fungus according to Gilman's method as a species Curvularia geniculata (Tracy and Earle) Boedjin.

• Animal cells and systems
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• v.10 no.3
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• pp.131-135
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• 2006

The ultrastructure of Aspergillus nidulans cell wall in relation to a mannoprotein was studied by scanning and transmission electron microscopy. An mnpAp null-mutant, DMPV1, was used as a negative control of a wild type VER7. To analyze whether the mannoprotein in the cell wall during the development of an mnpAp null-mutant is present or not, immunogold microscopy was also adopted. The surface sculpturing of various cell types - hyphae, conidium, Hulle cell, and ascospore - were not very different between the wild type and the mnpAp-null mutant (DMPV1) as examined by scanning electron microscopy. These results were comparable to those examined by transmission electron microscopy, in that the hyphal cell wall was not indentical between two strains, probably caused by the MnpA protein (MnpAp). MnpAp was absent in both the hyphal cell wall of the DMPV1 strain and the conidial cell wall of a wide type, but clearly recognized in the hyphal cell wall of a wild type.

• Mycobiology
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• v.50 no.6
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• pp.467-474
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• 2022

Autophagy serves as a survival mechanism and plays important role in nutrient recycling under conditions of starvation, nutrient storage, ad differentiation of plant pathogenic fungi. However, autophagy-related genes have not been investigated in Colletotrichum scovillei, a causal agent of pepper fruit anthracnose disease. ATG8 is involved in autophagosome formation and is considered a marker of autophagy. Therefore, we generated an ATG8 deletion mutant, ΔCsatg8, via homologous recombination to determine the functional roles of CsATG8 in the development and virulence of C. scovillei. Compared with the wild-type, the deletion mutant ΔCsatg8 exhibited a severe reduction in conidiation. Conidia produced by ΔCsatg8 were defective in survival, conidial germination, and appressorium formation. Moreover, conidia of ΔCsatg8 showed reduced lipid amount and PTS1 selectivity. A virulence assay showed that anthracnose development on pepper fruits was reduced in ΔCsatg8. Taken together, our results suggest that CsATG8 plays various roles in conidium production and associated development, and virulence in C. scovillei.