• Research in Plant Disease
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• v.20 no.2
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• pp.129-131
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• 2014

In February 2014, gray mold rotting symptoms were observed in carrots in cold storage at Gangneung, Gangwon province, Korea. The typical symptom of gray mold rot showed abundant blackish gray mycelia and conidia was observed on the infected root. The pathogen was isolated from infected root and cultured on PDA for further fungal morphological observation and confirming its pathogenicity according to Koch's postulates. Results of morphological data, pathogenicity test and rDNA internal transcribed spacer (ITS 1 and 4) sequence showed that the postharvest gray mold rot of carrot was caused by Botyrtis cinerea. This is the first report of postharvest gray mold rot on carrot in Korea.

• Korean Journal Plant Pathology
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• v.11 no.4
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• pp.348-352
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• 1995

Severe gray mold neck rot of onion occurred in most farmers' fields in the southern part of Korea, and 20∼50% of onions were infected by the disease at Goheung, Chonnam, in 1994. Symptoms of the disease appeared on the lower leaves near the soil surface in late February. The symptoms initially appeared as yellowish blotch with compact gray mold on the surface of the infected leaves and developed to blast of the aboveground parts of onions. As brown to dark brown symptoms progressed around the necks of onion later, the bulbs were rotting gradually. Botrytis sp. repeatedly isolated from the lesions produced the typical symptom on the neck of healthy onion 7 days after wound inoculation of conidial suspension of the fungus. The fungus reisolated from the bulbs was identified as Botrytis allii Munn based on the morphological and cultural characteristics and pathogenicity. This is first report of a gray mold neck rot of onion in Korea.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.467-472
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• 1998

Gray mold rot of perilla was epidemic at Kangdong, Pusan and Miryang, Kyungnam in 1997 and 1998. The incidence of this disease ranged form 21.3 to 68.1% at Kangdong area. Leaf necrosis initially appeared on the edge of the infected leaves, and it was developed to the center of the leaves forming typical V-shaped brown necrotic lesions. Under high moisture condition, abundant mycelia of the pathogen was formed on the surface of the lesions. Infected stems became slender and were completely blighted up to the top of the plant. Two isolates, LVF12 and SD7, were isolated from diseased lesions showing typical symptoms, and the pathogenicity was tested using mycelial disks and conidial suspension inoculation. The developed symptoms were same as the naturally produced ones. These two pathogenic fungi were identified as Botrytis cinerea based on the morphological characteristics using a microscope and a scanning electron microscope, and cultural characteristics. This is the first report of gray mold or perilla in Korea.

• Mycobiology
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• v.43 no.3
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• pp.339-342
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• 2015

The use of microorganisms and their secreted molecules to prevent plant diseases is considered an attractive alternative and way to supplement synthetic fungicides for the management of plant diseases. Strain BS062 was selected based on its ability to inhibit the mycelial growth of Botrytis cinerea, a major causal fungus of postharvest root rot of ginseng and strawberry gray mold disease. Strain BS062 was found to be closely related to Streptomyces hygroscopicus (99% similarity) on the basis of 16S ribosomal DNA sequence analysis. Postharvest root rot of ginseng and strawberry gray mold disease caused by B. cinerea were controlled up to 73.9% and 58%, respectively, upon treatment with culture broth of Streptomyces sp. BS062. These results suggest that strain BS062 may be a potential agent for controlling ginseng postharvest root rot and strawberry gray mold disease.

• Mycobiology
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• v.47 no.1
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• pp.87-96
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• 2019

Fungi produce various secondary metabolites that have beneficial and harmful effects on other organisms. Those bioactive metabolites have been explored as potential medicinal and antimicrobial resources. However, the activities of the culture filtrate (CF) and metabolites of whiterot fungus (Schizophyllum commune) have been underexplored. In this study, we assayed the antimicrobial activities of CF obtained from white-rot fungus against various plant pathogens and evaluated its efficacy for controlling anthracnose and gray mold in pepper plants. The CF inhibited the mycelial growth of various fungal plant pathogens, but not of bacterial pathogens. Diluted concentrations of CF significantly suppressed the severity of anthracnose and gray mold in pepper fruits. Furthermore, the incidence of anthracnose in field conditions was reduced by treatment with a 12.5% dilution of CF. The active compound responsible for the antifungal and disease control activity was identified and verified as schizostatin. Our results indicate that the CF of white-rot fungus can be used as an eco-friendly natural product against fungal plant pathogens. Moreover, the compound, schizostatin could be used as a biochemical resource or precursor for development as a pesticide. To the best of our knowledge, this is the first report on the control of plant diseases using CF and active compound from white-rot fungus. We discussed the controversial antagonistic activity of schizostatin and believe that the CF of white-rot fungus or its active compound, schizostatin, could be used as a biochemical pesticide against fungal diseases such as anthracnose and gray mold in many vegetables.

• Journal of Life Science
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• v.11 no.3
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• pp.242-247
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• 2001

Botrytis cinerea E12 was isolated from the leaves, flowers and fruits of eggplant in the greenhouse in Halrim, Kimhae and Dejeo, Pusan. The leaves infected with the pathogen were appeared initially brown-color, small gray spots at the edge, and finally fall down. The fruit was showed the symptoms of circular or irregular shapes, followed by sunken. When the symptoms were developed, the conidia formed on the surface with gray color. To determine the pathogenicity of B. cinerea E12 against the eggplants, the conidia were suspended with 30% tomato juice, PDB and sterile water, respectively. The result showed that the conidial suspension with 30% tomato juice was highly effective on the pathogenicity as more than 90%. Moreover, the symptoms caused by inoculum were the same as those of wild-type pathogen.

• Research in Plant Disease
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• v.20 no.4
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• pp.275-282
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• 2014

The occurrence of post-harvest diseases and their pathogens in 'Campbell Early' which is the most produced grape in Korea was investigated. The 'Campbell Early' grapes produced in 3 main grape-producing areas were stored in a cold room ($0-4^{\circ}C$) for 2 weeks then at room temperature for 4 weeks prior to investigation. The major post-harvest diseases occurred were gray mold, blue mold, ripe rot, new decay 1, and new decay 2. Pathogens isolated from the symptoms were identified as Botrytis cinerea for gray mold, Penicillium sclerotiorum for blue mold and Collectrichum acutatum for ripe rot. Pathogens for new decay 1 and new decay 2 were not identified yet. Incidences of new decay 1 and new decay 2 were much higher than the other 3 decays in all grapes produced from 3 areas. Gray mold and blue mold occurred at much lower frequencies than these two decays, and ripe rot occurred least.

• The Plant Pathology Journal
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• v.17 no.5
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• pp.305-307
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• 2001

In March 2000, gray mold was found on day lily (Hemerocallis fulva L.) in Korea. Among the symptoms observed was blight or early rot with chlorotic halo of the leaves. All the isolates obtained from the lesions of the diseased plant parts were identified as Botrytis elliptica, based on the morphological characteristics of conidia. Conidia that formed on conidiogenous cells were not in chains, hyaline to pale brown, unicellular, ellipsoidal to obovate with a single hilum at the base, entirely verruculose, and 21-31 x 12-$23\mu\textrm{m}$ in size. Pathogenicity of the fungus was established by artificial inoculation on day lily plants. This is the first record of gray mold on day lily caused by B. elliptica in Korea.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.90.2-91
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• 2003

In commercial greenhouses, senescent flower petals or flowers of vegetables such as tomato, strawberry, hot pepper and zucchini squash were blighted to be removed from fruits within five days after spraying of Trichoderma harzianum YC459 (TORY), a biocontrol agent for the gray mold rot of vegetables caused by B. cinerea The mechanism for selective colonization of senescent floral tissues by T. harzianum YC459 was elucidated using fresh and senescent (Hays and 14days after flowering, respectively) floral tissues of zucchini squash (Cucurbita moschata Duchesne). The spores of T. hrzianum YC459 were produced more on agar and liquid culture media supplemented with 5％ dry powder of senescent floral tissues than fresh tissues during 15days. Mycelial growth was also much better in the media with senescent tissues than with fresh tissues. Enzyme activities of amylase, polygalacturonase and cellulase in the liquid media which might be involved in the colonization of tissues by T. harzianum YC459 were compared. The activities of three enzymes were much higher in the media with senescent floral tissues than with fresh floral tissues reaching to the maximum during 9 to 12days of incubation. Based on the results, the removal of senescent floral tissues, a possible inoculum source of the pathogen, may be another mechanism for biocontrol of gray mold rot of vegetables by T. harzianum YC459.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.642-645
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• 1998

A severe pink mold rot on matured melon fruits occurred under a glass tunnel cultivation in Chinju at Kyeongasngnam-do Agricultural Research and Extention Services on May of 1998. Basal portion of the fruits toward blossom end was preferably infected and colonized by the fungus. The causal fungus consistently isolated from the lesions was identified as Trichothecium roseum based on following mycological characteristics. Conidia were hyaline or brightly colored, 2-celled, ovoid or elipsoid, characteristically held together zi-zag chains. Conidiophore was long, slender, simple, septate, bearing conidia-meristem arthrospores-apically, singly when young and successively by slight growth of conidiphore apex. Optimum temperature for mycelial growth and conidial germination was recorded at 20~$25^{\circ}C$. However, over 48% of the fungal conidia were germinated at 15$^{\circ}C$ and mycelial growth was only slightly slower than $25^{\circ}C$. The temperature profiles and high humidity available during the cultivation were considered favorable for the pathogen as showing 22% infection rate on matured melon fruits cv. Saros. This is the first report of pink mold rot of melon caused by T. roseum in Korea.