• The Plant Pathology Journal
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• v.15 no.3
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• pp.162-167
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• 1999

Integration of microbial antagonists with fungicides was tried to control the gray mold caused by Botrytis cinerea on pepper in greenhouse conditions and to reduce fungicide uses. All of the selected bacterial antagonists, Bacillus amyloliquefaciens BL3, Paenibacillus polymyxa BL4, and Pseudomonas putida Cha94, completely inhibited the conidial germination of B. cinerea until 30 days after treatment. However, bacterial colonization of pepper phylloplane was poor in BL4, while the other bacterial isolates and the fungal antagonist Trichoderma harzianum TM colonized well on the phylloplane, maintaining the population density of 104-105 cfu/g until 15 days after microbial treatments. Out of 13 kinds of selected fungicides used for gray mold diseases, polyoxin B and BKF 1995 showed the most discriminatory activity on the fungal growth between B. cinerea and TM. TM grew readily on the media containing those fungicides, while B. cinerea showed poor or no mycelial growth on them. The selected fungicides and antagonists alone reduced incidence of gray mold on pepper, showing disease indices of about 2.4 to 3.0, while its was increased up to 4.2 in the untreated control. Alternate treatments with the antagonists and 2-fold diluted fungicides inhibited the disease incidence as much as the antagonists or fungicides alone, and reduced the secondary inoculum more than the single treatments. This suggests that integration of antagonists and fungicides may be an efficient way to reduce fungicide sprays with reliable control efficacy of the disease. However, there was not much difference in the early and mid-term disease progress among the treatments and the untreated control, probably due to extremely favorable environmental conditions for the disease development in this experiment.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.655-668
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• 2012

Foliar diseases are major constraints to profitable organic tomato production. Especially, powdery mildew, leaf mold and gray mold of tomato occur severely on organic cultured tomatoes in Korea. This study was conducted to develop organic tomato cultivation technology using environmental-friendly disease control methods (resistance cultivar planting, air circulation fan installation, oil-egg yolk mixtures, and microbial agents). When tomatoes were cultivated in plastic film house installed with air circulation fan, daily range of temperature was decreased by $2{\sim}7^{\circ}C$, average relative humidity was decreased by 1~5% compared to those in plastic house without air circulation fan. Consequently, incidence of tomato leaf mold and tomato gray mold was reduced by 55.0% and 24.4%, respectively. Control effect of microbial agents and oil-egg yolk mixtures against major tomato diseases was examined in plastic house. As a result, the control value of microbial agents against tomato gray mold and tomato leaf mold showed at the range of 49.0~55.9 %(gray mold) and 39.2~58.2%(leaf mold), respectively. The control value of oilegg yolk mixtures against tomato powdery mildew showed 97.6%. Fifteen tomato cultivars were evaluated for disease resistance against leaf mold and powdery mildew in organically cultivated tomato field. Among 15 tomato cultivars, seven cultivars including 'Super-top' were found to be high resistant to tomato leaf mold. Also 'Powerking', one of fifteen tomato cultivars, showed to be high resistant to tomato powdery mildew.

• The Korean Journal of Mycology
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• v.45 no.3
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• pp.251-257
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• 2017

The occurrence of gray mold on Rubus crataegifolius has recently been reported in Pohang, Gyeongbuk province, Korea. The initial symptom was the appearance of small brown spots on the leaves, and these lesions became later covered with a gray fungus as the disease progressed. A fungus was isolated from symptomatic leaves and incubated. Through morphological and phylogenetic analyses, the causal agent of the disease was identified to be Botrytis cinerea. The fungal isolate was then used to inoculate on the leaves of healthy plants to determine its pathogenicity as the causal agent of gray mold as per Koch's postulates. The inoculated leaves showed the same symptoms as the originally infected plant, and the fungal pathogen re-isolated from the lesions showed the same morphological characteristics as the original pathogen. This is the first report on the occurrence of gray mold on R. crataegifolius caused by B. cinerea in Korea.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.438-444
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• 2007

Bacillus licheniformis N1 is a biological control agent to control gray mold diseases caused by Botrytis cinerea. Various formulations of B. licheniformis N1 were generated and evaluated for the activity to control strawberry gray mold. The wettable powder type formulation N1E was selected in pot experiments with remarkable disease control activity on both strawberry leaves and flowers. The N1E formulation contained 400 g of com starch, 50 ml of olive oil, and 50 g of sucrose per a liter of bacterial fermentation culture. Optimum dilution of N1E to appropriately control the strawberry gray mold appeared to be 100-fold dilution in plastic house artificial infection experiments. The significant reduction of symptom development in the senescent leaves was apparent by the treatment of N1E at 100-fold dilution when N1E was applied before Bo. cinerea inoculation, but not after the inoculation. Both artificial infection experiments in a plastic house and natural infection experiments in the farm plastic house under production conditions revealed that the disease severity of gray mold on strawberry leaves and flowers was significantly reduced by N1E treatment. The disease control value of N1E on strawberry leaves was 81% under production conditions, as compared with the 61.5% conferred by a chemical fungicide, iprodione. This study suggests that our previously generated formulation of B. licheniformis N1 will be effective to control strawberry gray mold by its preventive activity.

• The Plant Pathology Journal
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• v.21 no.1
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• pp.59-63
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• 2005

Bacillus subtilis S1-0210 was selected as a biological agent against Botrytis cinerea in strawberry. The isolate inhibited mycelial growth of B. cinerea in vitro tests. A wettable powder formulation of B. subtilis S1-0210 significantly reduced infection rates with lower than 5%, compared with higher than 70% of infection rates in untreated control. The formulation showed 85 to 89% control efficacies of gray mold incidences on fruits of strawberry in pots. Pre-treatment of the agent was more effective in controlling gray mold on fruits and leaves than post-treatment at the early stage of disease development. The formulation also showed 70% control efficacy of gray mold incidence on fruits of strawberry in a field trial. The results indicate that B. subtilis S1-0210 in the wettable powder formulation may be a potential biocontrol agent to control gray mold on strawberry.

• The Korean Journal of Pesticide Science
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• v.21 no.1
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• pp.90-96
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• 2017

Gray mold disease, cause by Botrytis cinerea, occurs severe damage on varieties of fruit and vegetable production, and have no a critical control method. In case of chemicals control, it is a trigger emergence of drug resistance strains due to using them continuously. In addition, the pathogen is difficult to control naturally because it is possible to survive regardless of host status. In this study, microorganisms were isolated from tomato flower and hive samples and in order to select suitable microbial control agents for tomato gray mold disease. During six-months study, we isolated 1,004 isolates from flower and 925 isolates from pollinator hive samples. Among them, 6 strains were selected based on result of antifungal activity test. The selected strains showed not only strong antifungal activity against gray mold pathogen, but also cellulase and protease enzyme activities. The selected strains were identified as Paenibacillus polymyxa. In plant assay, P. polymyxa prevented the gray mold disease occurrence near 75%.

• 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.

• Research in Plant Disease
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• v.9 no.1
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• pp.21-24
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• 2003

In May of 2002, the gray mold disease occurred severely on broad bean (Vicia faba) grown in farmer's fields located in Changseon-myon, Namhae-gun, Gyeongnam provice, Korea. The infected leaves, at first, discolored to gray or dark from the tip, and eventually died. Conidia of the fungus in mass were hyaline or gray, 1-celled, mostly ellipsoid or ovoid and sized 6~22$\times$4~16 ${\mu}{\textrm}{m}$. Thick conidiophores were formed on PDA with 15~37 ${\mu}{\textrm}{m}$ in width. The sclerotia were readily formed potato-dextrose agar and optimum temperature for sclerotial formation was 2$0^{\circ}C$. Pathogenicity of the causal organism was proved according to Koch's postulate. The causal organism was identified as Botrytis cinerea based on its mycological characteristics. This is tile first report on gray mold of broad bean (Vicia faba) caused by Botrytis cinerea in Korea.