• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.7 no.3
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• pp.92-96
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• 1986

고추에 피해를 주고 있는 병으로 잎오갈병, 더뎅이병, 탄저병, 역병등 19종이 우리나라에 보고 되어 있다. 이러한 고추의 병해를 병원균별로 보면 담배모자이크바이러스등 바이러스가 5종, 더뎅이병균등 세균이 3종이 있으며 곰팡이는 역병균등 14종이 고추에 병을 일으키고 있다. 이와같은 고추병들이 고추에 피해를 주고 있지만 그중에서도 특히 고추를 이어짓기 하는 밭이나 비닐하우스에서 고추의 작황을 좌우하는 것은 대부분이 역병에 의한 피해이다. 역병의 피해는 물론 고추를 이어짓기함으로써 토양 전염되는 역병균의 전염원이 매년 증가하기 때문이기도 하지만 역병이 발생하기 쉬운 여름철에 장마가 겹치므로 물빠짐이 나빠지거나 침수가 되기 때문에 피해가 증가하는 요인이 되고 있다.

• Journal of Life Science
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• v.9 no.1
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• pp.1-7
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• 1999

To isolate of antagonistic bacteria to Phytophthora capsici, which cause Phytophthora blight in red pepper, 237 isolates of Pseudomonas spp. and 260 isolates of Bacillus spp. were screened in selective media from rhizosphere soils of red pepper at Kyongsan, Kyongju, Yongchon and Euisung in Kyongbuk. Among total 497 isolates, 8 isolates of Pseudomonas spp and 4 isolates of Bacillus spp. inhibited the mycelial growth of Phytophthora capsici above 50$\%$ . These antagonistic bacteria showed more inhibitory effect on TSA (tryptic soy agar) than V-8 juice agar. Four isolates, P0704, P1201, B1101 and B1901, showing the most prominent antagonistic activity were selected and identified as P. cepacia (P0704, P1201), B. polymyxa (B1101) and B. subtilis (B1901), respectively. Cell free filtrates of these isolates were shown to inhibit zoosporangia germination and mycelial growth of p. capsici indicating that these isolates turned out to be bacteria producing antifungal substances. As a result of antagonistic test to Phytophthora blight in green house p. cepacia (P0704) showed the highest antagonistic effect with 46.7$\%$ and the rest of them were in the range of 13.4$\%$ to 26.7$\%$ .

• The Korean Journal of Mycology
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• v.20 no.3
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• pp.259-268
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• 1992

Fifty-three actinomycetes antagonistic to Phytophthora capsici and Magnaporthe grisea were isolated from rhizosphere soils in six pepper-growing areas and ashore soils. Thirty-two antagonistic actinomycetes, showing inhibition zone larger than 5 mm, were classified into 20 groups according to their colony morphology and color. The antagonistic activity against P. capsici greatly varied, which showed inhibition zone sizes in the ranges from 5.7 to 17.5 mm on V-8 juice agar and from 2.5 to 17 mm on tryptic soy agar. The antagonistic activity of some actinomycetes tested was remarkably different between the two test media. The antagonists showed a relatively broad antifungal spectrum, but their antibacterial activity was negligible, except for Pseudomonas solanacearum. Butanol extracts of culture filtrates from antagonistic actinomycetes inhibited mycelial growth of P. capsici and M. grisea, thereby confirming strongly antibiotic production in culture. Culture filtrates of some antagonistic actinomycetes completely inhibited Phytophthora blight in pepper plants.

• The Korean Journal of Pesticide Science
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• v.12 no.3
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• pp.270-276
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• 2008

Through the agar dilution method on V-8 juice agar, sensitivity of Phytophthora capsici causing pepper Phytophthora blight to metalaxyl was investigated by using isolates obtained from infected pepper plants during 3 years from 2005 to 2007. By the lapse of time, $EC_{50}$ value to metalaxyl was decreased, showing 1.45, 0.83, and $0.32{\mu}g\;mL^{-1}$ in 2005, 2006, and 2007. None of 2007 isolates was found to be resistant to metalaxyl. Compared the sensitivity of P. capsici isolates to metalaxyl with those to mandipropamid and dimethomorph, there is not a cross resistance response between metalaxyl and mandipropamid/dimethomorph. The resistance to metalaxyl in pepper Phytophthora blight pathogen was not related with the mycelial growth on V-8 agar medium and the pathogenicity on pepper plants.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.1
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• pp.44-51
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• 1992

Results as follows are obtained from the pot experiment to examine effect of application of organic substances on inhibition of occurrence of root rot of red pepper. 1. As for effects of applicating organic materials on inhibition of red pepper root rot, it is more effective to apply in autumn than to apply in summer, when the temperature is high. In addition, organic substance which is not decomposed completely such as rice straw is more effective than matured compost types. As for effects of applicating organic substances on composition of soil microorganisms, increase of fungi and bacteria in view of numbers is remarkable, especially in case of applying rice straw. 2. From the examination of Phytophthora capsici in soil at the 1st cultivation period in autumn, no P. capsici can be isolated in early stage of growth of red pepper in nontreated soil and in soil applied compost. However, as the time goes on, P. capsici are detected. While in early stage of cultivation, P. capsici are detected in soil applied with rice straw, P. capsici are not isolated after middle stage of cultivation. 3. It is recognized that there are many differences according to the types of organic materials applied in the result of identification of fungi in each treatment. And, proportion of antagonistic fungi to total fungi in soil applied rice straw is proved to be significantly higher compared to other treatments.

• Research in Plant Disease
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• v.16 no.2
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• pp.153-157
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• 2010

This study was examined to identify the race differentiation and distribution of mating type on Phytophthora capsici population in Korea. One hundred forty three isolates of P. capsici were collected from several locations of Korea in 2005-2007. In 2005, 20 isolates of P. capsici were collected and surveyed as A1 mating type of 75% and A2 mating type of 25%. In 2006, a total of 91 isolates were collected and separated as A1 mating type of 49.0%, A2 mating type of 42.9% and S type (sterile) of 3.3%. Isolates obtained in 2007 were similar to 2006 results. Totally, ratio of mating type of 153 isolates was confirmed that A1 type was 56.6%, A2 type was 39.2%, and S type was 4.2%. Thirteen pepper cultivars with different pathogenic response to 3 typical isolates having different mating were screened among 50 pepper cultivars and determined as race differential cultivars for investigation. The 11 races of P. capsici were found by using 13-race differential cultivars. These results indicated that at least 11 races of P. capsici are existed and confirmed race differentiation of P. capsici in pepper.

• 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.

• The Korean Journal of Pesticide Science
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• v.9 no.1
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• pp.102-107
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• 2005

To select microorganisms that exhibit antifungal activity against the fungal pathogens of pepper, Phytophthora capsici and Colletotrichum acutatum, soil samples from a forest and natural fields of Gajang-Dong, Sangju-city were tested in vitro and in vivo. Streptomyces griseofuscus 200401 was finally selected throughout antifungal activity test with dual culture, culture broth, and fruits. For the identification of the strain, nucleotide sequences of 16S rDNA and whole cell fatty acids were analyzed. It is like that the strain 200401 may be a novel biological control agent that can reduce application of chemical fungicides to control late blight and anthracnose on pepper.

• Korean Journal of Environmental Agriculture
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• v.15 no.3
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• pp.289-295
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• 1996

This study was attempted to select an antagonist against Phytophthora blight of red-pepper caused by Phytophthora capsici. The three strains, A-35, A-67 and A-183 were isolated from the rhizosphere in soil where red-pepper had been cultivated continuously for a long time, and the strain A-83 was estimated to be the strongest antagonist against P. capsici. The A-183 strain was identified as a strain of Pseudomonas sp., showing the maximum antifungal activity, when cultured at $30^{\circ}C$ for 5 days in the potato extract medium(pH 6.5) containing 2.0% mannitol and 0.3% peptone.

• Korean journal of applied entomology
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• v.20 no.2 s.47
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• pp.107-111
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• 1981

Effect of light and pH on mycelial growth and sporangium formation of Phytophthora capsici Leon, causal fungus of fruit rot of red pepper was carried out on culture media. The maximum mycelial growth occurred at $25^{\circ}C$ and pH 6.0 on potato sucrose agar. The fungus did not produce sporangia readily in dark condition. However, abundant sporulation occurred by illuminating continuous cool white fluorescent light with 2000 lux for 48 hrs. at $20{\pm}2^{\circ}C$. Oat meal agar was one of the best media for sporangia formation.