• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.104.2-105
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• 2003

Bacterial isolates, CC178, PTC25, HC39 and KY165 originally obtained from the leaves of cucumber or tomato were selected for biocontrol agents against gray mold of cucumber and tomato by in vivo cucumber seedling assay. Each suspension of the selected epiphytic bacteria were sprayed three times at seven-day interval from early stage of cucumber in a field. Incidence of gray mold on cucumber fruits treated with isolates CC178, PTC25, HC39 and KY165 was 15.3％, 18.2％, 23.6％, and 10.4％, respectively, whereas that of control was 38.0％ after 7 days of final spray. On the other hand, treatment with the selected isolates, CC178, PTC25, HC39, and KY165 on tomato showed 2.2％, 1.3％, 2.9％, and 3.5％ in the incidence of gray mold on leaves, whereas that of control was 9.3％. All selected isolates had strong antagonistic activity against Botrytis cinerea on dual culture plate assay.

• Research in Plant Disease
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• v.17 no.1
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• pp.75-77
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• 2011

Gray mold caused by Botrytis cinerea occurred on Saintpaulia ionantha in flower shop of the Jeonju city in Korea. Typical symptoms with brown water-soaked and rotting lesions were appeared on the flowers, leaves and petiole of infected plants. Many conidia spores appeared on the lesions under humid conditions. Colonies were grayish brown and sclerotial formation on potato dextrose agar. Conidia were one celled, mostly ellipsoidal or ovoid in shape, and were colorless to pale brown in color. The conidia were $7{\sim}14{\times}5{\sim}9\;{\mu}m$ in size. Based on pathogenicity and morphological characteristics of the isolated fungus, the causal fungus was identified as B. cinerea Persoon: Fries. Gray mold of S. ionantha was proposed to the name of this disease.

• Mycobiology
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• v.41 no.3
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• pp.164-166
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• 2013

A Bacillus sp. BS061 significantly reduced disease incidence of gray mold and powdery mildew. To identify the active principle, the culture filtrate was partitioned between butanol and water. The antifungal activity against B. cinerea was evident in the butanol-soluble portion, and active substances were identified as cyclic lipopeptides, iturin A series, by nuclear magnetic resonance spectrometry (NMR) and mass analysis. Interestingly, antifungal activity against powdery mildew was observed in the water-soluble portion, suggesting that cyclic lipopeptides have no responsibility to suppress powdery mildew. This finding reveals that biocontrol agents of Bacillus origin suppress gray mold and powdery mildew through the secretion of different bioactive substances.

• 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.

• The Korean Journal of Pesticide Science
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• v.19 no.3
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• pp.295-300
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• 2015

Currently, amount of export strawberry has been continuously increased to ship many south Asia countries, including Hong Kong and Singapore. In the distribution process, significant damage to the quality has been caused depending on the environmental conditions. Gray mold disease caused by Botrytis cinerea has been known as major damage to the export strawberry, and the disease was caused during shipping and distribution to the final consumers. This study was performed to assess the relationship between pathogen density in packing shed and disease incidence of gray mold during storage period. Maximum gray mold disease incidence in storage period was up to 16% with low temperature condition ($4^{\circ}C$). At room temperature condition, the disease incidence reached up to 100% even densities of the pathogen spore were recorded relatively low in the packing shed. As results of the study, the correlation between pathogen density in the air and disease occurrence clearly clarified.

• The Plant Pathology Journal
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• v.25 no.2
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• pp.165-171
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• 2009

Biological control activity of Acremonium strictum BCP, a mycoparasite on Botrytis cinerea, was examined against six plant diseases such as rice blast, rice sheath blight, cucumber gray mold, tomato late blight, wheat leaf rust, and barley powdery mildew in growth chambers. The spore suspension of strain BCP showed strong control activities against five plant diseases except against wheat leaf rust. On the other hand, the culture filtrate of A. strictum BCP was effective in controlling only cucumber gray mold and barley powdery mildew. Further in vivo biocontrol activities of A. strictum BCP against tomato gray mold were investigated under greenhouse conditions. Control efficacy of the fungus on tomato gray mold increased in a concentration-dependent manner. Treatment of more than $1{\times}10^6$ spores/ml significantly controlled the disease both in tomato seedlings and in adult plants. The high disease control activity was obtained from protective application of the strain BCP, whereas the curative application did not control the disease. Foliar infections of B. cinerea were controlled with $1{\times}10^8$ spores/ml of A. strictum BCP applied up to 7 days before inoculation. In a commercial greenhouse, application of A. strictum BCP exhibited the similar control efficacy with fungicide procymidone (recommended rate, $500{\mu}g/ml$) against strawberry gray mold. These results indicate that A. strictum BCP could be developed as a biofungicide for Botrytis diseases under greenhouse conditions.

• The Plant Pathology Journal
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• v.35 no.5
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• pp.425-436
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• 2019

Botrytis cinerea, a major phytopathogenic fungus, has been reported to infect more than 200 crop species worldwide, and it causes massive losses in yield. The aim of this study was to evaluate the inhibitory abilities and effects of Bacillus amyloliquefaciens RS-25, Bacillus licheniformis MG-4, Bacillus subtilis Z-14, and Bacillus subtilis Pnf-4 and their culture filtrates and extracts against the gray mold caused by B. cinerea on postharvest tomato, strawberry, and grapefruit. The results revealed that the cells of Z-14, culture filtrate of RS-25, and cells of Z-14 showed the strongest biocontrol activity against the gray mold on the strawberry, grape, and tomato fruit, respectively. All the strains produced volatile organic compounds (VOCs), and the VOCs of Pnf-4 displayed the highest inhibition values. Based on headspace solid-phase microextraction in combination with gas chromatography-mass spectrometry, esters accounted for the largest percentage of the VOCs produced by RS-25, MG-4, Z-14, and Pnf-4 (36.80%, 29.58%, 30.78%, and 36.26%, respectively). All the strains showed potent cellulase and protease activities, but no chitinase activity. RS-25, Z-14, and MG-4, but not Pnf-4, grew on chrome azurol S agar, and an orange halo was formed around the colonies. All the strains showed biofilm formation, fruit colonization, and lipopeptide production, which may be the main modes of action of the antagonists against B. cinerea on the fruit. This study provides the basis for developing natural biocontrol agents against the gray mold caused by B. cinerea on postharvest fruit.

• Research in Plant Disease
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• v.9 no.3
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• pp.145-148
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• 2003

In April of 2002, the gray mold disease occurred severely on kalanchoe (Kalanch oe blossfeldiana) grown in a nursery in Daesan-myon, Changwon City, Korea. The lesions were started with water-soaked spot and the leaves discolored from the tip and became gray or dark and gradully expanded to whole leaf. The conidia and mycelia of pathogen appearedd on flower, flower stalk and stem. Conidia were gray, 1-celled, mostly ellipsoid or ovoid in shape and were 8~17 ${\times}$5~12${\mu}m$ in size. Conidiophores were 13~34${\mu}m$ in size. The sclerotia were formed abundantly on potato-dextrose agar. The optimum temperature for sclerotial formation was $20^{\circ}C$. Pathogenicity of the causal organism was proved on Kalanchoe blossfeldiana according to Koch,s postulate. The causal organism was identified as Botrytis cinerea based on mycological characteristics. This is the first report on gray mold of Kalanchoe(Kalanchoe blossfeldiana) caused by Botrytis cinerea in Korea.

• Research in Plant Disease
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• v.10 no.4
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• pp.337-340
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• 2004

In April of 2003, the gray mold disease caused by Botrytis cinerea was occured in zinnia seedlings grown in greenhouse at Gyeongsangnam-do Agricultural Research and Extension Services, and farmer's nursery. The symptoms of infected plants were started with water-soaking lesions in flower bud, leaves and stems. The lesions gradually expanded and infected plants became withered and discolored to gray or dark from the tip. The conidia and mycelia of the pathogen were appeared on flowers, leaves and stem. The conidia were gray, 1-celled, mostly ellipsoid or ovoid in shape and were 5${\sim}$16 ${\times}$ 4${\sim}$8 ${\mu}m$ in size. Conidiophores were 12${\sim}$28 ${\mu}m$ in size. The pathogenic fungi formed sclerotia abundantly on potato dextrose agar. The optimum temperature for sclerotial formation was $20^{\circ}C$. Pathogenicity of the causal organism was proved according to Koch's postulate. The causal organism was identified as Botrytis cinerea Persoon: Fries based on mycological characteristics. This is the first report on gray mold of Zinnia elegans caused by Botrytis cinerea in Korea.

• Research in Plant Disease
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• v.8 no.1
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• pp.66-69
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• 2002

In February of 2002, the gray mold disease occurred severely on primular(primular spp.) grown in a flower nursery farm in Jinju, Korea. At first, the infected leaves were discolored to gray or dark from the tip and gradually expanded to die. The fungus attacked not only leaves but petals, calyx flower stalk and stems. Conidia of the fungus in mass were hyaline or gray, 1-celled, mostly ellipsoid or ovoid and sized 6.8~16.9$\times$4.6~12.4 $\mu$m. Conidiophores were wide of 15.9~31.6$\mu$m in size. The sclerotia were readily formed potato-dextrose agar and optimum temperature far sclerotial formation was 2$0^{\circ}C$. Pathogenecity of the causal organism was and preyed according to Koch\`s postulate. The causal organism was identified as Botrytis cinerea based on mycological characteristics. This is the first report on gray mold of primula caused by Botrytis cinerea in Korea.