• Mycobiology
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• v.31 no.3
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• pp.179-182
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• 2003

A total of 187 endophytic fungi were isolated from 11 plant species, which were collected from 11 locations in Korea. Their antifungal activities were screened in vivo by antifungal bioassays after they were cultured in potato dextrose broth and rice solid media. Antifungal activity against plant pathogenic fungi such as Magnaporthe grisea(rice blast), Corticium sasaki(rice sheath blight), Botrytis cinerea(tomato gray mold), Phytophthora infestans(tomato late blight), Puccinia recondita(wheat leaf rust), and Blumeria graminis f. sp. hordei(barley powdery mildew) was determined in vivo by observing the inhibition of plant disease development. Twenty(11.7%) endophytic fungi fermentation broths were able to control, by more than 90%, at least one of the six plant diseases tested. Among 187 liquid broths, the F0010 strain isolated from Abies holophylla had the most potent disease control activity; it showed control values of more than 90% against five plant diseases, except for tomato late blight. On the other hand, fourteen(7.5%) solid culture extracts exhibited potent disease control values of more than 90% against one of six plant diseases. The screening results of this study strongly suggested that metabolites of plant endophytic fungi could be good potential sources for screening programs of bioactive natural products.

• Korean Journal of Organic Agriculture
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• v.6 no.2
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• pp.117-125
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• 1998

For isolation of antagonistic fungi antagonistic to Phytophthora capsici, a total of 157 isolates of fungi were screened from soil. Among the 157 isolates further screened by the dual culture test on potato dextrose agar and V-8 juice agar, 16 isolates were tested to show their antagonistic activity against P. capsici and Fusarium oxysporum. Fungal cul-ture filtrates of screened 16 isolates were shown to inhibit germination of zoospoorangia of P. capsici entirely and conidia of F. oxysporum considerably. Antagonistic fungi were shown to suppress of P. capsici infection of red-pepper plants maintained in the green house. Four isolates. 27 J5, 37 J10, 36 J13 and 31 K10, with the reduced disease incidence 53.3∼60.0% were identified as Fusarium sp. (27 J5). Trichoderma sp. (37 J10, 36 J13) and Penicillium sp. (31 K10).

• The Plant Pathology Journal
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• v.17 no.5
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• pp.290-294
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• 2001

Forty(40) isolates of Fusarium oxysporum isolated from wilting tomato plants at Buyeo of Korea in 1997 were inoculated to four tomato cultivars (Ponderosa, Okitsu 3, Walter, and Zuiken) to examine pathogenic reactions. Isolation rates of F. oxysporum f. sp. lycopersici (FOL) races 1 and 2, and F. oxysporum f. sp. radicis-lycopersici(FORL) were 3.5%, 24.5%, and 57.5%, respectively. Mycelial growth on potato-dextrose agar at different temperature for the three pathogens was $26^{\circ}$. In the pathogenicity tests, however, the range of optimum temperature for disease development for FORL was between 15 and $20^{\circ}$, while that for races 1 and 2 of FOL were specifically pathogenic to tomato only. This suggests that host ranges of FORL and FOL differ significantly.

• The Plant Pathology Journal
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• v.18 no.1
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• pp.1-5
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• 2002

The availability of nucleotide sequences of the coat protein gene of Potato leafroll virus (PLRV) permitted the construction of DNA primers that were utilized for cDNA synthesis. Polymerase chain reaction (PCR) products of a 487 bp. and approximately 500 bp DNA fragments were amplified from nucleic acid extracts of PLRV-infected tissue and strawberry mild yellow-edge (SMYE) diseased strawberry tissue, respectively. The amplified DNA fragments were further differentiated by hybridization analysis with a CDNA probe for the coat protein gene of PLRV and restriction fragment length polymorphism (RFLP) analysis. These results suggest that a luteovirus is associated with the SMYE disease.

• Mycobiology
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• v.32 no.2
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• pp.98-101
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• 2004

A fruit soft rot caused by Mucor piriformis occurred on sweet persimmon storages in Jinju, Changwon and Gimhae, Gyeongnam province, Korea, 2003. The disease infection usually started from wounding after cracking of fruits. At first, the lesions started with water soaked and rapidly softened and diseased lesion gradually expanded. Colonies on potato dextrose agar at $20^{\circ}C$ were whitish to olivaceous-buff Sporangia were globose, black and $96{\sim}153{\mu}m$ in size. Sporangiophores were $26{\sim}42{\mu}m$ in width. Sporangiospores were ellipsoid and $5.8{\sim}10.6{\times}4.3{\sim}7.6{\mu}m$ in size. Columella was obovoid, cylindrical-ellipsoidal, pyriform, subglobose and $80{\sim}125{\mu}m$ in size. Optimal temperature for mycelial growth was $20^{\circ}C$ on PDA. The causal organism was identified as M. piriformis. This is the first report of fruit soft rot on sweet persimmon caused by M. piriformis in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.sup1
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• pp.29.1-29.1
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• 2009

• Mycobiology
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• v.39 no.3
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• pp.230-232
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• 2011

In this study, we characterized sporadically occurring sclerotium rot caused by Sclerotium rolfsii in Chinese chive (Allium tuberosum Roth.) in farm fields in Sacheon, Korea. The initial symptom of the disease was water-soaked, which progressed to rotting, wilting, blighting, and eventually death. Further, mycelial mats spread over the lesions near the soil line, and sclerotia formed on the scaly stem and leaves. The sclerotia were globoid, 1~3 mm, and white to brown. The optimum temperature for growth and sclerotia formation on potato dextrose agar (PDA) was $30^{\circ}C$. The diameter of the hypae ranged from 4 to 8 ${\mu}m$. Clamp connection was observed on PDA medium after 5 days of incubation. Based on the mycological characteristics, internal transcribed spacer sequence analysis, and pathogenicity test, the causal agent was identified as Sclerotium rolfsii Saccardo. This is the first report of sclerotium rot in Chinese chive caused by S. rolfsii in Korea.

• The Plant Pathology Journal
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• v.15 no.5
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• pp.308-310
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• 1999

A fungus associated with gray blight on tea plant (Camellia sinensis) was identifed as Pestalotiopsis theae based on the mycological characteristics. Mycelial growth on potato dextrose agar and size and shape of conidia of P. theae were similar to those of P. longiseta, but P. theae was different from P. longiseta in the color of three median cells and the number of apical appendages. Artificial inoculation of conidial suspension or mycelial mats on the wounded leaves and shoots of healthy plants induced the same disease, respectively. The Korean native variety was relatively. The Korean native variety was relatively more resistat to P. theae than a Japanese variety‘Yabukita’which has bee recently introduced and planted in large areas of southern parts of Korea. Here, we report the report the first record of gary blight caused by P. theae on tea plant in Korea.

• Research in Plant Disease
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• v.28 no.1
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• pp.46-50
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• 2022

In June 2017, in Gangneung, Gangwon Province, South Korea, green pea pods exhibited post-harvest rot symptoms. The fungus was isolated from infected pea pods and cultured on potato dextrose agar for identification. The morphological characteristics were examined, sequences of the internal transcribed spacer region and the β-tubulin (βtub) gene were analyzed, and the pathogenicity was confirmed according to Koch's postulates. The morphology, phylogenetic analysis, and pathogenicity tests confirmed that Sclerotinia sclerotiorum was the causal agent. This study reports the first case of post-harvest green pea pod rot caused by S. sclerotiorum in Korea.

• Korean journal of applied entomology
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• v.1
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• pp.37-41
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• 1962

Fifty three varieties of potatoes were planted at Alpine Potato Research station at Takwalyong Kangwando Province since in 1962. The varieties planted were introduced front Japan, the United States and Germany. The varietal reaction was divided into five classes, and the results were following. Immune : Kennebec, Isola, Cherokee, Merrimack, Yoraku, Lisili. Cosima. Highly Resistant : Antze, Ragis Isola, Hessenkrone, Plymouth, Sebago, Pungo, Sieglinde, Anco, Essex. Resistant : Tawa, B-605-10, Sequoia, Grata, Concordia, Onaway, Holing 1. Nisego. Susceptible: Nordak, Pontiac, Benimaru, Early Gem, Chippewa, Chitose, Ohjiro, Red Bake, Norland, Katahdin. Highly Susceptible: Russet Burbunk, May Queen, Earlaine, Irish Cobbler, Feldeslohn, Red Warba, Chisago, Osseo, Paunee. Warba, Norgleam, Red Beauty, Red Burt, Danshaku, Namchak (Native variety), In general the verieties introduced from the United States and Germany were more resistant to late blight than those introduced from Japan. Especially the German varieties were immune or highly resistant to the disease except Feldeslohn. Early maturing varieties were more susceptible to late blight than the late maturing varieties in southern Korea.