• 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.

• Research in Plant Disease
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• v.17 no.1
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• pp.1-12
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• 2011

Incidence of Phytophthora blight of hot pepper (Capsicum annuum) and yield (fresh weight) of pepper fruits were investigated at four separate fields located in Cheongwon, Boeun, Eumsung, and Goesan, which are major pepper production areas in Chungcheongbuk-Do. In all of the experimental fields except the Goesan field, increased incidence of Phytophthora blight led to decreased yield of pepper fruits. The harvest time in which the yield of red pepper fruits was highly correlated with the incidence of Phytophthora blight was different between areas: it was highly correlated in the third harvest in Cheongwon (y=-11.0x+435.2, $r^2$=0.99), but in the second harvest in Boeun (y=-15.0x+944.6, $r^2$=0.76). In contrast, there was a very low correlation between the pepper yield and the disease incidence in Goesan in which pepper seedlings grafted on resistant stocks were planted. The final disease incidence in the Cheongwon experimental field reached 100% more than 40 days later in 2007 compared with that in 2006. The control threshold of Phytophthora blight in the pepper fields where disease incidence had been lower than 5% was set as 0.8% disease incidence, which caused less than 5% yield loss.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.802-809
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• 2010

Phytophthora blight of pepper is the most economically important disease in the world cultivation regions. We investigated the phytophthora blight resistance of 300 accessions of Korean landrace of hot pepper germplasms collected from 83 local regions. The disease incidence rate was checked from 7 days to 28 days at an interval of 7 days after inoculation under greenhouse conditions. Among 300 accessions, the disease incidence rate of phytophthora blight of 67 accessions of pepper germplasm was more than 60.1%, while no disease was observed in 37 accessions at 7 days after inoculation. At 28 days after inoculation, five and eleven accessions of pepper germplasm were resistance and moderate resistance to $P.$ $capsici$, respectively. Two hundred forty four susceptible accessions (81.3%) of pepper were scored as having more than 60.1% of disease incidence of phytophthora blight. This result suggests that five candidate pepper germplasm might be used as breeding resources for the phytophthora blight resistance breeding program. Also, further genetic studies should be carried out to verify this result, with the overall focus of providing information on important characteristics of pepper germplasm.

• 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.

• 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.

• Research in Plant Disease
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• v.19 no.3
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• pp.208-215
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• 2013

3-(4-Hydroxyphenyl)-propionic acid (HPP) is a bacterial metabolite synthesized and released by an entomopathogenic bacterium Xenorhabdus nematophila K1. In this study, the control efficacy of HPP was tested against Phytophthora blight and anthracnose of red pepper plants. HPP suppressed mycelial growth of Phytophthora blight and anthracnose pathogens. Under natural sunlight condition, HPP maintained the antifungal activity on the diseases for at least twenty five days. The antifungal activity was not decreased even in the condition of soil-water. It was proved that HPP was able to penetrate the roots and travel upward of the red pepper plants. When HPP suspension was applied to soil rhizosphere before transplanting the red pepper seedlings or was regularly sprayed to the foliage of the plants with ten days interval, it resulted in significant reduction of the disease occurrences (Phytophthora blight and anthracnose) without any phytotoxicity. These results suggested that HPP can be developed to a systemic agrochemical against Phytophthora blight and anthracnose of red pepper plants.

• 농업기술회보
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• v.51 no.3
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• pp.23-24
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• 2014

시설고추는 노지고추와 달리 역병, 탄저병 등의 발생이 거의 없어 해충관리만 잘하면 약제사용을 크게 줄일 수 있다. 친환경으로 해충을 관리할 수 있는 방법은 천적곤충을 이용하는 것이며, 그 방법과 효과는 다음과 같다.

• Research in Plant Disease
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• v.8 no.3
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• pp.131-145
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• 2002

• Agrochemical news magazine
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• v.23 no.3 s.176
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• pp.22-25
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• 2002

• Research in Plant Disease
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• v.16 no.1
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• pp.106-108
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• 2010

This survey was conducted to investigate effect of covering with polyvinyl ($120{\times}90cm$) on incidence of Phytophthora blight and anthracnose and growth. Early growth of pepper plant was superior when was covered with polyvinyl after planting. Incidence of anthracnose and Phytophthora blight was lower 26.9% and 60.3% in covering system than those in conventional culture system, respectively. A yield of dried red pepper was more 48.5% in cultured with covering system than that in conventional culture system.