• The Korean Journal of Mycology
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• v.27 no.4 s.91
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• pp.280-282
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• 1999

A new disease on mask melon grown under plastic film houses was found in Namhae area in May of 1999. Gray to dark brown mold were grown on the surface of matured fruits and infected inside tissues were discolored and rotten. Basal part of the fruit and blossom-end were frequently infected and colonized by fungi. About 2.2% of matured fruits were infected in the surveyed plastic film houses. The causal organism was isolated from the lesion and identified as Botrytis cinerea. The conidia in mass were hyaline or gray, 1-celled, mostly ellipsoid or ovoid and sized $8.8{\sim}21.2{\times}6.5{\sim}13.1\;{\mu}m$. Hyaline or pigmented conidiophores were tall, slender and determinated and, sometimes branched irregularly in upper part. Enlarged or rounded apical cells bear conidial cluster and sized $18.4{\sim}81.1{\times}4.3{\sim}11.4\;{\mu}m$. Optimum temperature for mycelial growth was recorded at $15{\sim}25^{\circ}C$. This is the first report on gray mold of melon caused by Botrytis cineria in Korea.

• 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.

• 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.

• Research in Plant Disease
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• v.12 no.1
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• pp.40-45
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• 2006

The plant defence activator, Acibenzolar-S-methyl [benzo (1,2,3) thiadiazole-7-carbothioic acid-S-methyl ester, ASM] was assayed on tomato seedlings for its ability to induce resistance against Botrytis cinerea, the causal agent of gray mold in tomato. Pre-treatment of plants with ASM reduced the severity of the disease as well as the growth of the mycelium in plants. In ASM treated plants, reduction in disease severity (up to 55%) was correlated with suppression of mycelia growth (up to 46.5%) during the time course of infection. In plants treated with ASM, activities of peroxidase were determined as markers of resistance. Applications of ASM induced Progressive and significant increase of the enzyme in locally treated tissues. Such responses were expressed earlier and with a much higher magnitude when ASM-treated seedlings were challenged with the pathogen, thus providing support to the concept that a signal produced by the pathogen is essential for triggering enhanced synthesis and accumulation of the enzymes. No such activities were observed in water-treated control plants. Therefore, the slower symptom development and reduction in mycelium growth in ASM treated plants might be due to the increase in activity of oxidative and antioxidative protection systems in plants.

• The Korean Journal of Pesticide Science
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• v.11 no.2
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• pp.59-66
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• 2007

Three dimensional quantitative structure-activity relationships (3D-QSARs) on the fungicidal activity of N-phenyl-O-phenylthionocarbamate analogues against resistant and sensitive gray mold (Botrytis cinerea) (RBC & SBC) were studied quantitatively using CoMFA and CoMSIA methods. The correlation coefficient and predict- ability of optimized CoMFA model with the atom based fit alignment were better ($r^2$ & $q^2=CoMFA{\gg}CoMSIA$) than that of CoMSIA model. And statistical values of the models on the fungicidal activity against SBC were showed higher ($r^2=SBC{\gg}RBC$) than that of RBC. In CoMFA models, steric field on the activity was more influenced than electrostatic field. And in case of CoMSIA models, the influence of CoMSIA field on the activity against RBC and SBC was differ from each other but the influence of H-bond donor field was same to the two fungi. It is revealed that the selectivity factor with CoMFA model on the fungicidal activity between the two fungi was caused on the difference of steric field. Therefore, it is predicted that the large steric field with meta- and para-substituents on the N-phenyl ring will be improved to the fungicidal activity with SBC.

• The Korean Journal of Pesticide Science
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• v.3 no.1
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• pp.29-36
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• 1999

A series of N-phenyl-O-phenylthionocarbamate derivatives were synthesized and determinated fungicidal activities in vitro against gray mold (Botrytis cinerea) and capsicum phytophthora blight (Phytophthora capsici) which showed resistance and sensitivity to benomyl and metalaxyl as systemic fungicides, respectively. The structure-activity relationship (SAR) was investigated by Free-Wilson analysis method and Hansch method. From the basis on the findings, the N-phenyl(X) groups had more contributions than O-phenyl(Y) groups did and ortho-substituents on the N-phenyl group showed high fungicidal activities. Especially, 4-cyano substituent, 2 as X-group showed 50% inhibition($pI_{50}=5.50$) of hyphae growth at 0.8ppm against resistance P. capsici (RPC) And hydroxyl substituents, 12 and 23 displayed the highest fungicidal activity against resistant B. cinerea (RBC), sensitive B. cinerea (SBC), and sensitive P. capsici (SPC). Antifungal activities of SPC were dependent upon molar refractivity (MR) constant and those of others relied on hydrophobic parameters (${\sigma}$ and logP). For increasing fungicidal activity against RPC and SBC, the optimum values of the sigma (${\sigma}$) and field(F) constants as electron withdrawing groups were 0.32 and 0.18, respectively.

• Applied Biological Chemistry
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• v.37 no.4
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• pp.287-294
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• 1994

New 3-phenyl-1-(2-furyl)propenones, 1 and 3-phenyl-1-(2-furyl)-3-thiophenyl-propanone, 2 derivatives were synthesized, and their fungicidal activities in vitro against Botrytis cineria (BC), Valsa ceratosperma (VC), Scelerotium cepivorum (SC) and Phytophthora capsici (PC) were investigated using a generalized structure-activity relationship (SAR). The activity of 1 was superior to those of 2, and nonsubstituent, 1a and chloro group substituent, 1d of E (Syn) conformer were the most effective $(EC_{50}=10{\sim}12\;ppm)$ compound to BC. Antifungal activities were able to predict to depend essentially on the ${\beta}$ carbon and their positive charge from the results that the good correlation $(r^2=0.90)$ was observed between hydrolysis rate constant (logk) of 1 and the electronic parameter $({\sigma})$ of X-substituent on the ${\beta}-phenyl$ ring.

• Research in Plant Disease
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• v.16 no.3
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• pp.316-319
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• 2010

The gray mold disease occurred on tuberous roots of yacon in storage facilities in Gangneung, Korea, in March 2010. Symptoms typically appeared as in the form of dark brown discoloration on the surface of tuberous roots and water-soaked brown lesions in cross sections of the affected portions. A total of five isolates of Botrytis sp. were obtained from the symptomatic portions. All isolates on potato-dextrose agar (PDA) produced abundant conidia which were pale brown, one-celled, mostly ellipsoid or ovoid in shape and $8.2{\sim}14.8{\times}6.5{\sim}9.9\;{\mu}m$ in size. Large numbers of round to irregular, smooth, black, hard sclerotia were produced on PDA over time. The optimal temperature for mycelial growth and sclerotia formation of the fungal isolates was $20^{\circ}C$. On the basis of morphological and cultural characteristics, all the fungal isolates were identified as Botrytis cinerea. Pathogenicity test on host plants showed that the fungus could infect not only tuberous roots but also leaves and petioles of yacon. This is the first report on gray mold of yacon (Smallanthus sonchifolius) caused by Botrytis cinerea in Korea.

• Korean Journal of Environmental Agriculture
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• v.14 no.3
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• pp.319-328
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• 1995

This study was carried out to investigate the resistance mechanism by three different kinds of procymidone-resistant and susceptible isolates of Botrytis cinerea which had been collected from green houses. The average resistance level of the resistant strains was 1,000 times higher than that of susceptible ones. Also, it was revealed that the resistance was not originated from components excreted by Botrytis cinerea, based on the result obtained from the treatment with piperonyl butoxide and triphenyl phosphate as an inhibitor of monooxygenase and esterase, respectively. The total lipod content of resistant strains was 1.3 times higher than that of susceptible ones, among fatty acids, palmitic acid, stearic acid, and linoleic and being 3.0, 2.5, and 2.0 times higher, respectinely. Also slight differences in sterol contents and components were observed. The crude chitin content was slightly higher in susceptible strains but contents of N-acetyl glucosamine, a hydrolysate of chitin, were about 2 times higher in resistant ones.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.307-314
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• 2008

Sixty compounds such as alkylphenyl fluorobenzoate esters from thymol(I), 5-isopropyl-3-methylphenol (II), 4-isopropyl-3-methylphenol (III), 2-sec-butylphenol (IV) and 4-sec-butylphenol (V) were synthesized. These derivatives were identified by IR, $^1H$-NMR spectrometer and GC/MS. Their in vivo antifungal activities were tested against phytopathogens such as Phytophthora infestans, Botrytis cinerea, Colletotrichum orbiculare and Rhizoctonia solani. As the result, 2-sec-butylphenyl 2,5-difluorobenzoate (IV-6) and 4-sec-butylphenyl 2,5-difluorobenzoate (V-6) showed 90% above antifungal activity against Botrytis cinerea. 2-Isopropyl-5-methylphenyl 2,3,6-trifluorobenzoate (I-11), 2-isopropyl-5-methylphenyl 2,4,5-trifluorobenzoate (I-12), 5-isopropyl-3-methylphenyl 2,3,6-trifluorobenzoate (II-11), 4-isopropyl-3-methylphenyl 2,3,6-trifluorobenzoate (III-11) and 4-isopropyl-3-methylphenyl 2,4,5-trifluorobenzoate (III -12) showed 90% above potent antifungal activity against Colletotrichum orbiculare.