• Proceedings of the Korean Society of Plant Pathology Conference
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• 1994.06a
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• pp.50-61
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• 1994

Biological control of important fungal diseases such as Phytophthora blight of red pepper, gary mold rot of vegetables, and powdery mildew of many crops was attempted using an antagonistic bacterium, Bacillus sp. AC-1 in greenhouses and fields. The antagonistic bacterium isolated from the rhizosphere soils of healthy red pepper plant was very effective in the inhibition of mycelial growth of plant pathogenic fungi in vitro including Phytophthora capsici, Rhizoctonia solani, Pyricularia oryzae, Botrytis cinerea, Valsa mali, Fusarium oxysporum, Pythium ultimum, Alternari mali, Helminthosporium oryzae, and Colletotrichum gloeosporioides. Culture filtrate of antagonistic Bacillus sp. AC-1 applied to pot soils infested with Phytophthora capsici suppressed the disease occurrence better than metalaxyl application did until 37 days after treatment in greenhouse tests. Treatments of the bacterial suspension on red pepper plants also reduced the incidence of Phytophthora blight in greenhouse tests. In farmers' commercial production fields, however, the controlling efficacy of the antagonistic bacteria was variable depending on field locations. Gray mold rot of chinese chives and lettuce caused by Botrytis cinerea was also controlled effectively in field tests by the application of Bacillus sp. AC-1 with control values of 79.7% and 72.8%, respectively. Spraying of the bacterial suspension inhibited development of powdery mildew of many crops such as cucumber, tobacco, melon, and rose effectively in greenhouse and field tests. The control efficacy of the bacterial suspension was almost same as that of Fenarimol used as a chemical standard. Further experiments for developing a commercial product from the antagonistic bacteria and for elucidating antagonistic mechanism against plant pathogenic fungi are in progress.

• 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.

• Research in Plant Disease
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• v.13 no.3
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• pp.177-182
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• 2007

In this experiment, 236 isolates of Botrytis cinerea isolated from the lesions of ginseng grey mold in 2005 and 2006 were examined for their sensitivity to fungicide inhibiting ${\beta}-tubulin$ assembly. The baselines of fungicide resistance were determined as 10.0 and $0.2{\mu}g/ml$ of $EC_{50}$ values for carbendazim and the mixture of carbendazim and diethofencarb, respectively. The ratios of isolates resistant to carbendazim in 2005 and 2006 was investigated to be 87.6 and 96.6%, respectively. In the case of the mixture of carbendazim and diethofencarb, the ratio of the resistant isolates was 23.6% for 2005 and 24.5% for 2006. The ratio of the resistant isolates to the mixed fungicide was fluctuated according to regions where isolates of B. cinerea were obtained. In Yeoncheon of Gyeonggi Province, 4.3% of the isolates used in the experiment was resistant in 2005 and no resistant isolate was obtained in 2006. Among 5 regions, the ratio of resistant isolates was the highest as 70.0% in Yecheon of Gyeongbuk Province.

• Korean Journal of Plant Resources
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• v.30 no.5
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• pp.542-548
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• 2017

Two different races of Botryris cinerea were selected by the response of plant leaves to the pathogen infection. Based on lesion size of the pathogen on the leaves, turnip showed susceptible response to 'Grape-01' race, and resistant to 'Orange' race. Turnip leaves infected with resistant pathogen race, "Orange", showed significantly higher content of indole-3-ylmethyl glucosinolate (I3M) than those infected with susceptible race, 'Grape-01'. Contents of I3M in the leaves with resistant 'Orange' race was 2.5 times as high as that in uninfected leaves, whereas I3M in the leaves infected with susceptible 'Grape-01' race showed lower content than in untreated leaves. Growth of turnip suspension cells was significantly inhibited by the treatment of MeOH extract or water extract of 'Orange' race as compared with the treatment of susceptible race, 'Grape-01'. Treatment of MeOH or water extract from 'Orange' race to turnip suspension cells, strongly inhibited cell viability up to 22.7% or 16.5%, respectively. However, plant cells treated with MeOH or water extract from resistant race, 'Orange' showed higher I3M content than that from susceptible race, 'Grape-01'. These results suggest that accumulation and degradation of I3M glucosinolate in turnip cells closely related to the resistance and susceptibility of turnip cells to Botrytis cinerea.

• Korean Journal of Agricultural Science
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• v.19 no.2
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• pp.170-178
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• 1992

Isolates of Botrytis cinerea resistant to dicarboximide fungicides were collected from strawberry fields in greenhouses in spring and early summer of 1990. Five out of 9 isolates of B. cinera were resistant, which showed mycerial growth on PDA containing dicarboximide fungicides(procymidone and vinclozolin) with concentrations of 100, 400 and $1,600{\mu}g/ml$. The minimal inhibitory concentration(MIC) values of the dicaboximide-resistant isolates was more than $6,400{\mu}g/ml$, while that of the sensitive isolates was less than $6.25{\mu}g/ml$. The germination ratio of conidia of the resistant isolates on PDA containing procymidone and vincolozolin was more than 95%, while that of the sensitive was less than 15%. The procymidone-resistant isolates were also resistant to vinclozolin, showing cross-resistant between the fungicides, but cross-resistant was not observed between the dicarboximides and dichlofluanid. Resistance to benomyl was also found in all the dicarboximide resistant isolates. Occurrence frequency of dicarboximide-resistant isolates out of 223 isolates was about 40%. The resistant isolates were widely distributed throughout Korea.

• Horticultural Science & Technology
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• v.28 no.6
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• pp.1072-1077
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• 2010

Plant diseases including gray mold caused by Botrytis cinerea are often reduced when calcium compounds are used as alternative materials in paprika. However, much less information is available about the effects of calcium compounds on controlling of $B.$ $cinerea$. Seven calcium compounds such as calcium sulfate dihydrate, calcium chloride, calcium nitrate, calcium oxide, calcium hydroxide, calcium carbonate, and calcium hydride were evaluated for their effectiveness against $B.$ $cinerea$ on potato dextrose agar medium. The pH of selected calcium compounds was higher (pH 8.2-10) than that of the control (pH 6.6). Calcium carbonate, calcium oxide, calcium hydride, and calcium hydroxide among seven calcium compounds were more effectively inhibited the growth of $B.$ $cinerea$ than other calcium compounds. In the case of spraying the spore suspension on paprika applied with the selected four calcium compounds and supplied with the selected calcium supplements in a hydroponic culture system, the paprika treated with calcium compounds showed less severity of disease than those untreated plants. On the basis of our results, we propose that the suppressive effects of calcium compounds on $B.$ $cinerea$ in paprika resulted from the supply of calcium and a certain degree of salt stress.

• Mycobiology
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• v.42 no.3
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• pp.262-268
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• 2014

Several postharvest diseases of table grapes (Vitis vinifera) occur during storage, and gray mold rot is a particularly severe disease because the causal agent, Botrytis cinerea, grows at temperatures as low as $0^{\circ}C$. Other postharvest diseases, such as those caused by Penicillium spp. and Aspergillus spp., also often lead to deterioration in the quality of table grapes after harvest. The use of plant essential oils such as thymol and linalool, to reduce postharvest diseases in several kinds of fruits, including table grapes and oranges, has received much attention in European countries. However, to the best of our knowledge there has been no report of the use of thymol fumigation to control gray mold in table grapes in Korea. Thymol ($30{\mu}g/mL$) and linalool ($120{\mu}g/mL$) significantly inhibited mycelial growth and conidia germination of B. cinerea. The occurrence rate of gray mold rot of B. cinerea and other unknown fungi was significantly reduced by fumigation with $30{\mu}g/mL$ thymol in several table grape cultivars, such as Campbell early, Muscat Bailey A, Sheridan, and Geobong. In this study, fumigation with $30{\mu}g/mL$ thymol, had no influence on the sugar content and hardness of grapes, but reduced fungal infection significantly. This suggests that $30{\mu}g/mL$ thymol could be utilized to reduce deterioration of grapes due to gray mold and other fungal infections during long-term storage.

• Food Science and Preservation
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• v.15 no.6
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• pp.791-795
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• 2008

In order to establish the method to prepare and use the sulfur dioxide gas generating agent in low temperature storage of grape fruits, the $SO_2$ generation capacity from various sulfite compounds was investigated, and the method to regulate $SO_2$ gas generation and to detect the gas was developed. The conidial germination and mycelium growth of Botrytis cinerea which causes gray mold disease during grape fruit storage was completely inhibited at the $SO_2$ gas concentration of 400 ppm and 3200 ppm, respectively. Sodium hydrosulfite generated the most amount of $SO_2$ gas among the investigated 5 different sulfite or bisulfite compounds. By adjusting the number of pinholes on packaging film of the compound or by adding pH adjusting agent, e.g. citric acid or phosphates, it was possible to regulate the amount and duration of $SO_2$ gas generation from the compound. Because malachite green was quantitatively discolored by $SO_2$ gas, the solution or impregnated paper with the compound could be practically utilized as a indicator detecting $SO_2$ gas. Finally, when Muscat Bailey A grape was stored at low temperature with $SO_2$ gas generating agent, the disease incidence was reduced after storage.

• Molecules and Cells
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• v.24 no.2
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• pp.232-239
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• 2007

$HrpN_{EP}$, from the gram-negative pathogen, Erwinia pyrifoliae, is a member of the harpin group of proteins, inducing pathogen resistance and hypersensitive cell death in plants. When the $hrpN_{EP}$ gene driven by the OsCc1 promoter was introduced into tobacco plants via Agrobacterium-mediated transformation, their resistance to the necrotrophic fungal pathogen, Botrytis cinerea, increased. Resistance to B. cinerea was correlated with enhanced induction of SA-dependent genes such as PR-1a, PR2, PR3 and Chia5, of JA-dependent genes such as PR-1b, and of genes related to ethylene production, such as NT-EFE26, NT-1A1C, DS321, NT-ACS1 and NT-ACS2. However the expression of NPR1, which is thought to be essential for multiple-resistance, did not increase. Since the pattern of expression of defense-related genes in $hrpN_{EP}$-expressing tobacco differed from that in plants expressing $hpaG_{Xoo}$ from Xanthomonas oryzae pv. Oryzae, these results suggest that different harpins can affect the expression of different defense-related genes, as well as resistance to different plant pathogens.

• Korean Journal of Organic Agriculture
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• v.24 no.3
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• pp.465-484
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• 2016

This study evaluated the antifungal activity of varying concentrations of water-soluble extracts from native plants (Vitex rotundifolia, Tetragonia tetragonoides, Artemisia capillaris, Hibiscus hamabo and Ficus carica) against Stemphylium vesicarium, Penicillium italicum, Sclerotinia sclerotiorum, Pythium ultimum, Botrytis cinerea, Rhizoctonia solani and Colletotrichum gloeosporioides. Mycelium growth of pathogenic bacteria generally decreased in a concentration-dependent manner following treatment with the water extracts from donor plants. Closer analyses indicate varying inhibitory capacities depending on the type of donor plant and pathogenic bacteria. Specifically, mycelium growth of S. vesicarium varied depending on the concentration of the water extracts from T. tetragonoides (r = -0.857, p<0.01) and A. capillarys (r = -0.868, p<0.01). Also, P. italicum and V. rotundifolia (r = -0.833, p<0.01), S. sclerotiorum and V. rotundifolia (r = -0.862, p<0.01), A. capillaris (r = -0.902, p<0.01), B. cinerea and T. tetragonoides (r = -0.896, p<0.01) showed an inverse relationship. The rate of mycelial growth inhibition of pathogenic bacteria analysed are as follows: P. ultimum 94%, B. cinerea 50%, C. gloeosporioides 80% in 100% treatment of T. teragonoides. A. capillaris inhibited S. vesicarium by 43%, P. ultimum by 90%; H. hamabo inhibited P. italicum by 50%, S. sclerotiorum by 26%, and F. carica inhibited R. solani by 74%. Total phenol content with antifungal activities are as follows: A. capillaris 16.15 mg/g, F. carica 7.81 mg/g, V. rotundifolia 6.18 mg/g, H. hamabo 5.25 mg/g, T. tetragonoides 4.41 mg/g, and total flavonoid content is as follows: A. capillaris 27.57 mg/g, V. rotundifolia 12.49 mg/g, F. carica 11.45 mg/g, H. hamabo 5.77 mg/g, T. tetragonoides 5.08 mg/g.