• The Korean Journal of Mycology
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• v.14 no.2
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• pp.179-183
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• 1986

This survey was conducted to identify the fungal pathogens on the imported seeds during two months from September to October in 1985. Twenty-four species of fungi were detected from six kinds of the imported seeds and the following eight species of fungi have not been reported before in Korea.

• The Plant Pathology Journal
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• v.33 no.6
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• pp.597-601
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• 2017

The clpks18 gene was first cloned and identified in Curvularia lunata. It contains 6571 base pairs (bp) and an 6276 bp open reading frame encoding 2091 amino acids. The ClPKS18 deletion mutant displayed an albino phenotype, and almost lost the ability to product 5-(hydroxymethyl) furan-2-carboxylate (M5HF2C) toxin, implying that clpks18 gene in C. lunata is not only involved in 1,8-dihydroxynaphthalene melanin synthesis, but also relatively associated with M5HF2C toxin biosynthesis of the pathogen. The pathogenicity assays revealed that ${\Delta}ClPKS18$ was impaired in colonizing the maize leaves, which corresponds to the finding that ClPKS18 controls the production of melanin and M5HF2C in C. lunata. Results indicate that ClPKS18 plays a vital role in regulating pathogenicity of in C. lunata.

• Mycobiology
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• v.30 no.4
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• pp.225-227
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• 2002

The inhibitory activity of ent-norsecurinine alkaloid was evaluated against spore germination of some plant pathogenic fungi(Curvularia maculans, Curvularia species, C. palliscens, Colletotrichum gloeosporioides, Colletotrichum species, Afternaria solani, A. brassicae, Fusarium udum, Helminthosporium echinoclova and H. penniseti). It inhibited spore germination of all the test fungi. C. maculans, C. species, and C. palliscens were the most sensitive as complete inhibition of spore germination was observed at 1000 ppm. A. solani was not inhibited by this chemical.

• The Korean Journal of Mycology
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• v.51 no.3
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• pp.245-249
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• 2023

Prickly lettuce (Lactuca serriola), an invasive annual plant, poses a significant threat to the agricultural systems of many countries, including Korea. In 2020, leaf blight symptoms were observed in the prickly lettuce populations of various farms across Korea. Detailed morphological and molecular sequence analyses revealed that the disease was caused by the fungus, Curvularia intermedia. A pathogenicity test confirmed that the fungus can cause the same symptoms in healthy prickly lettuce, thereby fulfilling Koch's postulates. To the best of our knowledge, this is the first report of C. intermedia causing leaf blight on L. serriola in Korea, suggesting its potential as a biocontrol agent for this weed. However, further investigations are necessary to determine its ecological impact to prevent any non-target effects.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.108-114
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• 2015

Curvularia lunata is an important maize foliar fungal pathogen that distributes widely in maize growing area in China, and several key pathogenic factors have been isolated. An yeast two-hybrid (Y2H) library is a very useful platform to further unravel novel pathogenic factors in C. lunata. To construct a high-quality full length-expression cDNA library from the C. lunata for application to pathogenesis-related protein-protein interaction screening, total RNA was extracted. The SMART (Switching Mechanism At 5' end of the RNA Transcript) technique was used for cDNA synthesis. Double-stranded cDNA was ligated into the pGADT7-Rec vector with Herring Testes Carrier DNA using homologous recombination method. The ligation mixture was transformed into competent yeast AH109 cells to construct the primary cDNA library. Eventually, a high qualitative library was successfully established according to an evaluation on quality. The transformation efficiency was about $6.39{\times}10^5$ transformants/$3{\mu}g$ pGADT7-Rec. The titer of the primary cDNA library was $2.5{\times}10^8cfu/mL$. The numbers for the cDNA library was $2.46{\times}10^5$. Randomly picked clones show that the recombination rate was 88.24%. Gel electrophoresis results indicated that the fragments ranged from 0.4 kb to 3.0 kb. Melanin synthesis protein Brn1 (1,3,8-hydroxynaphthalene reductase) was used as a "bait" to test the sufficiency of the Y2H library. As a result, a cDNA clone encoding VelB protein that was known to be involved in the regulation of diverse cellular processes, including control of secondary metabolism containing melanin and toxin production in many filamentous fungi was identified. Further study on the exact role of the VelB gene is underway.

• Mycobiology
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• v.39 no.3
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• pp.206-218
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• 2011

The seed-borne mycoflora of sorghum and foxtail millet collected from different growing areas in South Korea were isolated and taxonomically identified using dry inspection, standard blotter and the agar plate method. We investigated the in vitro and in vitro germination rates of disinfected and non-disinfected seeds of sorghum and foxtail millet using sterilized and unsterilized soil. The percent recovery of seed-borne mycoflora from the seed components of sorghum and foxtail millet seeds was determined and an infection experiment using the dominant species was evaluated for seedling emergence and mortality. A higher number of seed-borne fungi was observed in sorghum compared to that of foxtail millet. Eighteen fungal genera with 34 fungal species were identified from the seeds of sorghum and 13 genera with 22 species were identified from the seeds of foxtail millet. Five dominant species such as Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme and Phoma sp. were recorded as seed-borne mycoflora in sorghum and 4 dominant species (Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme) were observed in foxtail millet. The in vitro and in vitro germination rates were higher using disinfected seeds and sterilized soil. More seed-borne fungi were recovered from the pericarp compared to the endosperm and seed embryo. The percent recovery of seed-borne fungi ranged from 2.22% to 60.0%, and Alternaria alternata, Curvularia lunata and 4 species of Fusarium were isolated from the endosperm and embryo of sorghum and foxtail millet. Inoculation of the dominant seed-borne fungi showed considerable mortality of seedlings. All the transmitted seed-borne fungi might well be a primary source of infection of sorghum and foxtail millet crops.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.04a
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• pp.15.1-15
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• 1999

• Mycobiology
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• v.33 no.2
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• pp.97-103
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• 2005

Crude extracts and active principles from medicinal plants have shown potential role in controlling plant diseases in glasshouses as well as in fields as one of the safest and ecofriendly methods. The effect of nor-securinine (an alkaloid) isolated from Phyllanthus amarus has been seen against spore germination of some fungi (Alternaria brassicae, A. solani, Curvularia pennisetti, Curvularia sp., Erysiphe pisi, Helminthosporium frumentacei) as well as pea powdery mildew (Erysiphe pisi) under glasshouse conditions. The sensitivity of fungi to nor-securinine varied considerably. Nor-securinine was effective against most of the fungi. H. frumentacei was more sensitive even at the lowest concentration ($1,000\;{\mu}g/ml$). Likewise conidia of E. pisi were also inhibited in partially or completely appressorium formation. Pre-inoculation treatment showed greater efficacy than post-inoculation in inhibiting powdery mildew development on pea plants in a glasshouse. Maximum inhibition occurred at $2000\;{\mu}g/ml$.

• Mycobiology
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• v.32 no.4
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• pp.160-163
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• 2004

Medicinal plants play important roles in controlling plant diseases as one of the safest and ecofriendly methods. These plants have been used in the form of crude extracts as well as active principles in vitro and under field conditions to control plant diseases. Among the active principles, alkaloids have shown significant antifungal activity. We have investigated the effect of two alkaloids viz., (-)-corydahnine and (-)-isocorypahnine isolated from Corydalis chaerophylla, against spore germination of some plant pathogenic and saprophytic fungal spores. Significant inhibition of spore germination at 100 ${\mu}g/ml$ was seen against Curvularia penniseti, Curvularia sp. and Colletotrichum gloeosporioides by (-)-corydahnine but (-)-isocorypalmine was also effective against fungi included in the experiment.

• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.199-205
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• 1985

1. Alternaria tenuis, Cladosporium cladosporioides, Curvularia lunata Fusarium semitectum, Gerlachia oryzae, Phoma sp. Trichoconiella padwickii were found associated with ear blighting of rice plants. The frequency of isolation of the fungi was found to be higher from the severely discolored rice grains than that from the brownish spotted grains, but H. oryzae was encounted highly from the latter. 2. Higher counts of Alternaria tenuis, Helminthosporium oryzae, Trichoconiella padwickii, Fusarium moniliforme, Fusarium semitectum were observed under alternating cycles of 12hrs of light and darkness than under complete darkness but G. oryzae was encountered highly under darkness in the blotter. While no difference in the occurrence of the other fungi was recorded under l2hr NUV light-12hr darkness cycles and darkness. 3. A. tenuis and C. cladosporioides were encountered highly at the lower temp. $(15^{\circ}C)$ but Phoma sp. was occurred highly at the higher temp. $(30^{\circ}C)$ when the seeds were incubated in the blotter. 4. Artificial inoculation of the fungi in the ears of rice plants caused severe discoloration of rice grains and reduced 1,000 grain weights and grain ripening percentage.