• 한국유기농업학회지
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• 제23권1호
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• pp.133-148
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• 2015

Although several adverse effects have been increased in recent years, synthetic agro-chemicals have been widely used to control diseases on paprika. This research was conducted to isolate and to characterize the antagonistic microorganism to control major paprika diseases, gray mold rot, fruit and stem rot, phytophthora blight, sclerotium rot, and wilt disease. Analysis of the fatty acid and analysis of the 16S rDNA gene sequence revealed that YKJ2 isolated in this research belongs to a group of Burkholderia cepacia. Specially, 16S rDNA gene sequence of YKJ2 showed 99% of sequence similarity with B. cepacia. Observation through the optical microscope revealed that YKJ2 was effective on suppression of the spore germination and the hyphal growth of pathogens. YKJ2 treatment on pathogens induced marked morphological changes like hyphal swelling and degradation of cell wall. In the case of phytophthora blight, the zoosporangium formation was restrained. On the basis of the results of this study, we propose that an antagonistic microorganism, B. cepacia, found in this study naming as "B. cepacia strain YKJ2" and has great potential as one of biological control agents against major diseases of paprika.

• Journal of Ginseng Research
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• 제4권2호
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• pp.186-193
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• 1980

The causal organism of Phytophthora disease on Panax ginseng Meyer in Korea was isolated and identified as Phytophthora cactorum. It's pathogenicity, etiology, and possible control measures were investigated. Disease symptoms on various parts of ginseng plants were also described The fungus caused seedling and mature plant blight and root rot. Oospores were easily formed on potato dextrose agar and corn meal agar. Oospores, however, were not formed in the diseased root tissues but did in the in footed shoots such as leaves, petioles, and stems and in the inoculated berries.

• 한국균학회지
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• 제33권2호
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• pp.98-102
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• 2005

2003년부터 2005년 사이에 한국의 두릅나무에 심각한 역병이 발생하였다. 감염된 두릅나무와 토양으로부터 병원균이 분리되었으며, 이 균은 배양적인 그리고 형태적인 특징 및 병원성 검증 실험에 의해 P. cactorum(Lebert&Cohn) J. Schrt.으로 동정되었다. 이 균은 뚜렷한 돌출형이고, 둥근 난형모양의 탈락성 유주포자낭의 특정으로 다른 역병균으로부터 형태적으로 구분되었다. 최적의 생장 온도는 V8 배지와 Oat meal 배지에서의 $25^{\circ}C$이었다. PCR을 통해 ITS rDNA 영역의 약 900 bp의 길이가 증폭되었으며, 세 가지 효소인 Alu I, Msp I, Taq I을 이용한 PCR-RFLP 분석 결과를 PhytID 의 데이터베이스에서 분석한 결과 형태적인 그리고 배양적인 특징에 의한 결과와 일치했다.

• The Plant Pathology Journal
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• 제29권1호
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• pp.87-92
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• 2013

This study was conducted to determine the Phytophthora rot resistance of 514 accessions of watermelon germplasm, Citrullus lanatus var lanatus. About 46% of the 514 accessions tested were collections from Uzbekistan, Turkey, China, U.S.A., and Ukraine. Phytophthora capsici was inoculated to 45-day-old watermelon seedlings by drenching with 5 ml of sporangial suspension ($10^6$ sporangia/ml). At 7 days after inoculation, 21 accessions showed no disease symptoms while 291 accessions of susceptible watermelon germplasm showed more than 60.1% disease severity. A total of 510 accessions of watermelon germplasm showed significant disease symptoms and were rated as susceptible to highly susceptible 35 days after inoculation. The highly susceptible watermelon germplasm exhibited white fungal hyphae on the lesion or damping off with water-soaked and browning symptoms. One accession (IT032840) showed moderate resistance and two accessions (IT185446 and IT187904) were resistant to P. capsici. Results suggest that these two resistant germplasm can be used as a rootstock and as a source of resistance in breeding resistant watermelon varieties against Phytophthora.

• 농약과학회지
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• 제6권4호
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• pp.287-292
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• 2002

양액재배 토마토에 심각한 피해를 주는 역병균에 대한 효과적인 방제방법을 조사하였다. 역병 방제용으로 사용되고 있는 3종의 약제를 선정하여 실내 스크리닝을 통하여 역병균에 대한 높은 방제효과를 나타낸 metalaxyl copper oxychloride 수화제(15% metalaxyl+35% copper oxychloride) 및 dimethomorph.dithianon 수화제(8% dimethomorph+30% dithianon) 2 종을 선발하고, 유묘검정을 통하여 이들 약제의 최적처리농도를 5,000배액으로 정하였다. 약제처리 시험은 토마토를 암면에 정식하고 40일 후에 역병균을 접종하였으며, 역병처리 5일 후 선발된 약제를 5,000배액으로 희석하여 암면당 약 0.5 L씩 1회${\sim}$3회 살포하였다. 약제살포 후 15일에 토마토 및 양액을 각각 채취하여 잔류농약을 분석한 결과 metalaxyl과 dithianon은 토마토에서 검출되지 않았고 dimethomorph는 2회와 3회 처리구의 토마토에서 각각 0.001과 0.003 mg/kg 검출되었으나 토마토의 잔류허용기준(1.0 mg/kg)에는 크게 미달하였다. 또한, 양액시료중 농약잔류량은 토마토 수확 당일 3회 처리구에서 metalaxyl 1.242 mg/kg, dimethomorph 0.726 mg/kg, dithianon 2.875 mg/kg이 각각 검출되었다. 역병 방제효과시험에서 약제를 1회 및 2회 처리시 metalaxyl copper oxychloride 수화제 처리구에서 발병율은 $30.5{\sim}50%$이었으며, dimethomorph.dithianon 수화제 처리구에서는 $16.7%{\sim}25%$의 발병율을 나타내었다. 그러나 3회 처리구에서는 역병이 전혀 발병되지 않았으며, 모든 처리구에서 약해는 관찰되지 않았다. 따라서, 양액재배 토마토의 역병 방제를 위해서는 metalaxyl copper oxychloride 수화제 또는 dimethomorph dithianon 수화제를 각각 5,000배로 조제하여 암면에 15일 간격으로 3회 관주처리(약 0.5 L/회/주) 하는 것이 방제효과와 생산물의 안전성 측면에서도 만족스러운 것으로 확인되었다.

• The Plant Pathology Journal
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• 제35권6호
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• pp.698-704
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• 2019

Phytophthora root and stem rot (PRSR) caused by Phytophthora sojae is one of the most destructive diseases of soybean. PRSR recently became an issue as soybean cultivation in paddy fields increased in South Korea. The management of PRSR mainly involves R-gene-mediated resistance, however, little is known about the resistance in Korean cultivars. Major Korean soybean cultivars were investigated for the presence or absence of R-gene-mediated resistance to four P. sojae isolates, two of which were new isolates. Isolate-specific reactions were observed following P. sojae inoculation. Of 21 cultivars, 15-20 cultivars (71.4-95.2%) showed susceptible reaction for each isolate. Ten cultivars were susceptible to all the isolates, and six cultivars were identified to have R-gene-mediated resistance to one or two isolates. The results of this study would provide a framework for the discovery of resistant cultivars, development of new cultivars resistant to P. sojae, and investigation of pathogenic diversity of P. sojae population in South Korea.

• The Plant Pathology Journal
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• 제22권1호
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• pp.103-106
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• 2006

In this biocontrol research, we evaluated disease suppressive effects of antagonistic bacterial strains ISE13 and KJ1R5 against Korean ginseng root rot caused by P. eaetorum. We also examined the effects of nutrient solution in the hydroponic culture system for Korean ginseng on biological activity of the bacterial strains. As results of dual culture tests of the bacterial strains on $V_{8}$ juice agar, the strain ISE13 showed antifungal activity against P. eaetorum and other plant pathogenic fungi, but the strain KJ1R5 did not. When their inhibitory effects against infection of P. eaetorum on the roots grown in either nutrient solution or water were tested, the strains ISE13 and KJ1R5 inhibited the disease severity of Korean ginseng roots only grown with water, compared to buffer-treated, inoculated controls. However, the nutrient solution used for hydroponic cultures of ginseng in pots caused higher levels of disease severity by the strains ISE13 and KJ1R5 from 418.8\%$ to 40.0\%$ and from 24.3\%$ to 45.0\%$, respectively. In this study, the bacterial strains ISE13 and KJ1R5 could be potentially biocontrol agents to suppress Korean ginseng root rot caused by P. eaetorum. However, more attention using nutrient solution in hydroponic cultures for Korean ginseng production should be applied in biocontrol of plant diseases using the antagonistic microorganisms.

• The Plant Pathology Journal
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• 제18권5호
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• pp.288-292
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• 2002

Crude extract of Xanthium strumarium inhibited mycelial growth and zoospore germination of Phytophthora drechsleri, the causal agent of Atractylis rot, in vitro. Fresh sap from X. strumarium at 50-fold dilution was highly effective in controlling the disease Incidence in pot and field trials. Purified extracts from cocklebur Inhibited mycelial growth and zoospore germination in vitro at a concentration of 12.5 $\mu\textrm{g}$/ml and 15.6 $\mu\textrm{g}$/ml, respectively. Hyphal tips affected by the compound showed malformation. The antifungal compound puri- fied fromX. strumarium was identified as 4-oxo-1 (5), 2,11, (13)-xanthatriene-12,8-olide, known as "deacetyl xanthumin".min".uot;.

• 원예과학기술지
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• 제30권1호
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• pp.64-72
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• 2012

고추 역병은 그 동안 우리나라 고추 생산에 있어서 심각한 수량감소의 피해를 주어 왔으며, 2004년 처음으로 고추 역병 저항성 품종이 보급되기 시작하면서, 국내 건고추 육종에 있어서 역병 저항성의 도입은 필수불가결한 것으로 되었다. 그러므로 저항성 식물체 선발의 정확성 제고 및 육종의 효율 향상을 위하여 역병 저항성과 연관된 분자표지의 개발이 요구된다. 지금까지 고추 역병 저항성 주동 유전자에 연관된 분자표지가 일부 개발되어 있지만, 부분적으로 밖에 사용할 수 없다는 문제점이 있다. 따라서 본 연구에서는 역병 저항성 소재에 상관없이 저항성을 구별해 낼 수 있는 분자표지를 개발하고자 하였다. 이를 위해 '수비초' ${\times}$ 'CM334' 조합의 $F_2$ 분리집단($SF_2$)과 역병 저항성 시판 $F_1$품종('독야청청')을 자가수정한 $F_2$ 분리집단($DCF_2$)을 만들었다. BSA-AFLP 방법으로 총 1,024 프라이머 조합을 사용하여 역병 저항성과 연관된 세 개의 AFLP 분자표지(AFLP1, AFLP2 및 AFLP3)를 선발하였으며, 이를 CAPS 분자표지(M1-CAPS, M2-CAPS 및 M3-CAPS)로 전환하였다. 이 중 M3-CAPS 분자표지를 10개의 역병 저항성 계통, 14개의 이병성 계통, 'CM334'를 화분친으로 사용한 5개의 $F_1$ 조합, 그리고 53개의 시판 $F_1$ 품종에 적용해 본 결과, 역병 저항성 표현형과 M3-CAPS 분자표지의 마커형이 잘 일치하였고, P5-SNAP과 Phyto5.2-SCAR 분자표지보다 높은 실용성을 보이는 결과를 얻었다. 따라서, M3-CAPS 분자표지는 역병 저항성 고추 계통 육성에 많은 도움을 줄 수 있을 것으로 생각한다.

• The Plant Pathology Journal
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• 제17권6호
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• pp.379.3-379
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• 2001