• The Korean Journal of Mycology
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• v.16 no.2
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• pp.60-63
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• 1988

Each of 103 isolates of Phytophthora capsici was obtained from diseased red pepper plants randomly belonged to either the mating type $A_1$ or the mating type $A_2$. Fifty four isolates were classified as mating type $A_1$, and 49 isolates were classified as mating type $A_2$.Oospores were formed in each combination of isolates between $A_1$ or $A_2$ on 5% V-8 juice agar except one combination.

• Korean journal of applied entomology
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• v.14 no.2 s.23
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• pp.77-79
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• 1975

Brown rot of eggplant caused by Phytophthora capsici has not been reported so far in Korea. The wide distribution of the disease was found at the central Korea including Suweon. The symptom of the disease was characterized by water sealing lesions at first, the color gradually turn brown and a little sunken area on the fruit appearred at the final stage. Dense hyphae and short sporangiophores grew out from the lesions, and they produce abundant zoosporangia on them. The disease was identified from buck-eye rot caused by Phytophthora parasitica in that the cottony growth of hyphae and rare zoosporangia formation. The pathogen was isolated and indentified on the basis of the pathogenecity and morphology comparing with P. parasitica.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2627-2634
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• 2012

Strobilurins are one of the most important classes of agricultural fungicides. To discover new strobilurin derivatives with high activity against resistant pathogens, a series of novel ${\beta}$-methoxyacrylate analogues were designed and synthesized by integrating substituted pyrimidine with a strobilurin pharmacophore. The compounds were confirmed and characterized by infrared, $^1H$ nuclear magnetic resonance, elemental analysis and mass spectroscopy. The bioassays indicated that most of the compounds (1a-1h) exhibited potent antifungal activities against Colletotrichum orbiculare, Botrytis cinerea Pers and Phytophthora capsici Leonian at the concentration of 50 ${\mu}g/mL$. Exhilaratingly, compound 1d (R=3-trifluoromethylphenyl) showed better antifungal activity against all the tested fungi than the commercial strobilurin fungicide azoxystrobin.

• Korean Journal Plant Pathology
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• v.14 no.2
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• pp.120-124
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• 1998

The conidial germination of Pestaotiopsis theae was occurred in cells attched with pedicels, the inferior cell of conidium. The cells were swollen like a ball, and then germinated in 4 hours under favorable conditions. Generally, it was considered that fifty percent of whole conidia was germinated in the range 6~12 hours. The optimum temperature and pH for conidial germination of P. theae (SP-3) causing leaf blight on sweet persimmon was $25^{\circ}C$ and pH 5, respectively. Conidial germination rate was higher than 90% at 100% relative humidity, but never germinated at a relative humidity lower than 88.5%. Conidial germination was highest at the concentration of 1~4$\times$104 conidia/ml. In case of cultural media, the conidial germination was higher than 90% on PDA, PSA, OME and Leonian agar. There was no relationship between light and conidial germination. It was concluded that the key environmental factors affecting conidial germination of the fungus (SP-3) were temperature and moisture.

• Current Research on Agriculture and Life Sciences
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• v.22
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• pp.13-18
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• 2004

Eighty five accessions of our laboratory pepper germplasm collections in 2003 were tested for resistance to Phytophthora capsici Leonian. Any new material highly resistant was not found among them. However, KC1184, which has horticultural characteristics of Korean peppers, was moderately resistant and appeared worthwhile in breeding for resistance.

• Journal of Life Science
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• v.11 no.6
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• pp.603-611
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• 2001

Phytolalexins are produced in plants affected by various environmental factors such as fungal infection treatment with many chemicals and irradiation by ultraviolet light. When pepper and tobacco bel suspension cultures were grown on a basal MS medium supplemented with 2,4-D(1mg/$\ell$, benzyl adenine(0.001 mg/$\ell$) and 100$\mu$ M jasmonic acid, the production of capsidiol was observed. The total of compound found in pepper plant were around seventy and thirty of them were located intissue-specific manner. 1-propanethiol, $\alpha$-D-xylofuranoside, phenol, hexadecanonic acid ethyl tridecanoate, phytol, linoleic acid and capsidiol are those which have change the production level by treatments, such as the inoculation of Phytophthora capsici Leonian, the metalaxyl treatment and the UV-B irradiation, respectively. The content of capsidiol on inoculation of P. capsici with metalxyl suspension in soil were higher than those of P.capsici without metalaxyl. When the soil dernch of metalaxyl treatment (1$\mu\textrm{g}$/${mu}ell$)was delayed after inoculation, the content of capsidiol were higher than that of before. Irrradiated UB-B the production on capsidiol was identified only at leaf, and contents were the highest for 24 hrs incubation after 20 minutes irradiation.

• Korean Journal of Environmental Biology
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• v.18 no.1
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• pp.47-51
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• 2000

Phytophthora blight of pepper, which is caused by Phytophthora capsici Leonian, is not only the most destructive disease worldwide, but also difficult to control effectively. It has been needed to have new trials for effective control to the disease. We employed radiation hormesis of gamma ray as the new trial in the control strategy. Two cultivars, Kwangbok and Dabok, were used to analyse whether gamma ray radiation can induce disease resistance. The germination rate of pepper seeds was significantly enhanced by the radiation at all dose levels. Stimulatory effect for resistance induction was found to differ between cultivars. It was confirmed that the remarkable effect was induced in Dabok and depended on radiation dosage. Disease resistance at 4 Gy was much higher than that of control. On the other hand, no detectable induction effect for resistance was observed in Kwangbok which was moderate resistant cultivar to gamma ray radiation. [Hormesis, Gamma ray, Pepper, Phytophthora blight, Resistance induction].

• Current Research on Agriculture and Life Sciences
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• v.9
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• pp.127-133
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• 1991

PI201232, a pepper line resistant to Phytophthora capsici Leonian, was crossed with PI2713222 and P1163192, resistant to Xanthomonas campestTis pv. vesicatoria (Doidge) Dye and inheritance of the resistance to each disease and genetic relationship between the two disease resistances was studied. Non-hypersensitive resistance to race 3 of X. c. pv. vesicatoria of PI271322 was inherited in a quantitative mode. Resitance to P. capsici of PI201232 was inherited in a mode close to two dominant alleles. Hypersensitive resistance to race 1 of X. c. pv. vesicatoria of PI271322 was inherited in a mode of single dominant allele. PI 163192 was consistently resistant to both race 1 and race 3 of X c. pv. vesicatoria and the resistance was inherited in a quantitative mode with high dominance effect. Resistance to X. c. pv. vesicatoria was inherited independently from resistance to P. capsici.

• The Plant Pathology Journal
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• v.36 no.6
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• pp.600-607
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• 2020

Phytophthora capsici Leonian is a major pathogen of pepper worldwide and few resistance sources to this pathogen have been identified so far. The goals of this study were to identify new sources of resistance against P. capsici in Capsicum landraces and analyze the relationship between the resistance indicator of plant symptoms and some plant phenotype parameters of plant height, stem width, leaf length and leaf width. Thirty-two landraces of pepper were collected from fourteen states in Mexico. From each population, 36 plants were inoculated with 10,000 zoospores of P. capsici under controlled conditions. This experiment was repeated twice. Out of the 32 landraces, six showed high level of resistance, four showed intermediate resistance and five showed low level of resistance when compared with the susceptible control 'Bravo' and the resistant control 'CM334', indicating that these landraces are promising novel sources of resistance to P. capsici. There was no correlation between the symptoms and plant phenotype parameters. However, these parameters were not affected in the group classified as highly resistant, indicating that P. capsici does not affect the growing of these resistant pepper landraces. The other resistant groups were significantly affected in a differently manner regarding their phenotype, indicating that this pathogen reduce their growth in different ways. This study reports novel resistance sources with great potential that could be used in breeding programs to develop new pepper cultivars with durable resistance to P. capsici.

• Korean Journal Plant Pathology
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• v.13 no.4
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• pp.232-238
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• 1997

Culture conditions affecting mycelial growth and sporulation of P. theae, SP2, SP3 and P. longiseta which causing leaf blight on oriental persimmon leaf blight have been investigated. The optimum temperature for the mycelial growth and sporulation on potato dextrose agar was $25{\sim}30^{\circ}C$ in all the fungi, but was inhibited and finally arrested at 10 and $30^{\circ}C$. The optimum pH for mycelial growth and sporulation were ranged at pH 4.5~5.0 and 5.0~6.0 in all the fungi. Lenonian agar, potato sucrose agar and oatmeal medium were good culture media for the mycelial growth and sporulation of all the fungi. The effective sources of nitrogen and carbon for the mycelial growth were tryptone, glycine, starch, dextrose, galactose and lactose. Glutamic acid, peptone and tryptone were good nitrogen sources for sporulation of the fungi. Sucrose, starch and galactose were also good carbon sources for sporulation. Generally, vitamins had no effect on mycelial growth and sporulation. The pH of the potato dextrose broth inoculated with SP2, SP3 and P. theae and P. longiseta was changed from 7.0 to 4.5~4.7 and 5.0~5.4 after incubating for 10 days, respectively. But, the initial pH of the medium adjusted to 5.0 was lowered to 4.5~4.7 after incubating for 10 days.