• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1999년도 임시총회 및 추계 학술발표회
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• pp.31.2-31
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• 1999

• 한국식물병리학회지
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• 제3권1호
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• pp.17-19
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• 1987

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 춘계학술대회
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• pp.97-97
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• 2022

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 추계학술대회 및 정기총회
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• pp.41-41
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• 2015

Oomycetes belong to the kingdom Straminipila, a remarkably diverse group which includes brown algae and planktonic diatoms, although they have previously been classified under the kingdom Fungi. These organisms have evolved both saprophytic and pathogenic lifestyles, and more than 60% of the known species are pathogens on plants, the majority of which are classified into the order Peronosporales (includes downy mildews, Phytophthora, and Pythium). Recent phylogenetic investigations based on DNA sequences have revealed that the diversity of oomycetes has been largely underestimated. Although morphology is the most valuable criterion for their identification and diversity, morphological species identification is time-consuming and in some groups very difficult, especially for non-taxonomists. DNA barcoding is a fast and reliable tool for identification of species, enabling us to unravel the diversity and distribution of oomycetes. Accurate species determination of plant pathogens is a prerequisite for their control and quarantine, and further for assessing their potential threat to crops. The mitochondrial cox2 gene has been widely used for identification, taxonomy and phylogeny of various oomycete groups. However, recently the cox1 gene was proposed as a DNA barcode marker instead, together with ITS rDNA. To determine which out of cox1 or cox2 is best suited as universal oomycete barcode, we compared these two genes in terms of (1) PCR efficiency for 31 representative genera, as well as for historic herbarium specimens, and (2) in terms of sequence polymorphism, intra- and interspecific divergence. The primer sets for cox2 successfully amplified all oomycete genera tested, while cox1 failed to amplify three genera. In addition, cox2 exhibited higher PCR efficiency for historic herbarium specimens, providing easier access to barcoding type material. In addition, cox2 yielded higher species identification success, with higher interspecific and lower intraspecific divergences than cox1. Therefore, cox2 is suggested as a partner DNA barcode along with ITS rDNA instead of cox1. Including the two barcoding markers, ITS rDNA and cox2 mtDNA, the multi-locus phylogenetic analyses were performed to resolve two complex clades, Bremia lactucae (lettuce downy mildew) and Peronospora effuse (spinach downy mildew) at the species level and to infer evolutionary relationships within them. The approaches discriminated all currently accepted species and revealed several previously unrecognized lineages, which are specific to a host genus or species. The sequence polymorphisms were useful to develop a real-time quantitative PCR (qPCR) assay for detection of airborne inoculum of B. lactucae and P. effusa. Specificity tests revealed that the qPCR assay is specific for detection of each species. This assay is sensitive, enabling detection of very low levels of inoculum that may be present in the field. Early detection of the pathogen, coupled with knowledge of other factors that favor downy mildew outbreaks, may enable disease forecasting for judicious timing of fungicide applications.

• The Plant Pathology Journal
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• 제18권2호
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• pp.77-80
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• 2002

A simple method for sporangial formation of the rice downy mildew pathogen, Sclerophthora macrospora, on infected leaf tissues was developed to facilitate diagnosis of the disease. Freshly infected young leaves showing whitish to yellowish small spots were selected and cut into small pieces about 2-3 cm in length. About 10-20 pieces were surface sterilized in a 100 ml Duran bottle with 40 ml of 70% ethanol by vigorous shaking for 30 seconds. After washing three times with distilled water, the leaf cuts were submerged in 10 ml of Millipore-filtered paddy water and incubated at $20^{\circ}C$ in the dark. After 8-10 h of incubation, the bottle was vigorously agitated on a vortex mixer, Aliquot amount of the suspension, 0.1-1.0 m1, was spread on a slide glass and examined under a light microscope at 50 or 100x magnification. It was found that light and 1% NaClO strongly inhibit sporangial formation of S. macrospora. Meanwhile, the use of freshly infected young loaves and washing with 70% ethanol stimulated sporangial formation of the fungus on rice leaves.

• Mycobiology
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• 제45권3호
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• pp.139-149
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• 2017

The genus Hyaloperonospora (Peronosporaceae; Oomycota) is an obligate biotrophic group that causes downy mildew disease on the Brassicaceae and allied families of Brassicales, including many economically relevant crops, such as broccoli, cabbage, radish, rape, and wasabi. To investigate the diversity of Hyaloperonospora species in northeast Asia, we performed a morphological analysis for the dried herbarium specimens collected in Korea, along with molecular phylogenetic inferences based on internal transcribed spacer rDNA and cox2 mtDNA sequences. It was confirmed that 14 species of Hyaloperonospora exist in Korea. Of these, three species, previously classified under the genus Peronospora, were combined to Hyaloperonospora: H. arabidis-glabrae comb. nov. (ex Arabis glabra), H. nasturtii-montani comb. nov. (ex Rorippa indica), and H. nasturtii-palustris comb. nov. (ex Rorippa palustris). In addition, finding two potentially new species specific to northeast Asian plants is noteworthy in support of the view that the species abundance of Hyaloperonospora has been underestimated hitherto.

• 농약과학회지
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• 제4권1호
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• pp.64-70
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• 2000

아인산의 고추 토마토 역병 및 노균병에 대한 방제 효과를 성체 식물체를 이용하여 온실에서 검정한 결과, 고추 역병의 경우 $1,408{\mu}g$ a.i./mL ($H_{3}PO_{3}$) 농도 처리에서 91%와 80%의 예방 및 치료효과를 보였다. 토마토 역병의 경우는 $1,408{\mu}g$ a. i./mL 처리에서 각각 63.4%와 13.0%의 예방 및 치료효과를 보여 고추 역병에 비해 효과가 저조하였다. 토마토 역병균의 유주자낭의 밀도가 $1{\times}10^{3}{\sim}1{\times}10^{4}/mL$일 경우 방제 효과가 높았다. 고추역병균에 대한 약제지속효과에 있어서 아인산은 경엽처리 4일 후에도 94%의 높은 방제 효과를 보여 대조약제인 포롬 수화제에 비해 효과가 지속됨을 알 수 있었다. 오이 노균병에 대해서는 $1,408{\mu}g$ a.i./mL 처리는 82와 62%의 예방 및 치료효과를 보였다. 아인산의 경엽처리는 식물의 생육을 촉진시키는 것으로 나타났다.

• 한국균학회지
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• 제45권4호
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• pp.386-393
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• 2017

우리나라 양파 재배지의 주요 곰팡이병인 양파 노균병의 원인균 Peronospora destructor를 채집하여, internal transcribed spacer (ITS) 영역을 포함한 4개 유전자의 염기서열을 분석하여 상동성 비교와 분자계통학적 유연관계를 분석하였다. 그 결과, 경남 창녕군, 함안군, 합천군과 전남 무안군, 신안군, 해남군에 발생하는 P. destructor의 4종의 유전자 염기서열 모두 100% 상동성을 보였고, 유연관계 분석에서도 모두 동일한 계통으로 확인되었다. 본 연구에서는 ITS 영역 유전자 염기서열을 이용하여 P. destructor 검출용 PCR법을 개발하였고, 노균병균만을 특이적으로 검출하였다. 또한 식물체를 포함한 total genomic DNA로 검출한계를 검정한 결과, $0.7ng/{\mu}L$까지 가능하였다. 양파 노균병균 검출용 PCR법은 육안상 병징이 나타나지 않을 때도 충분히 감염유무가 확인되었다.

• 한국응용곤충학회지
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• 제3권
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• pp.11-14
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• 1964

1, 본 시험은 2개년에 걸쳐(1963-1964) 부산에서 양파로균병방제를 위하여 신살균제 6종을 공시하여 종래에 사용하여 오던 석회보르도와 비교시험하였다. 2. 약제처리구는 무처리에 비하여 방제효과를 인정할 수 있었으며 특히 Difolatan과 Dithane M 45는 그 효과가 우수하였으며 Dithane M22, Dithane Z 78, Orthocide도 석회보르도보다 효과가 좋았으며 산키농은 석회보르도와 함께 전자에 비해 약간 효과가 떨어지는 것을 알 수 있었다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1999년도 임시총회 및 추계 학술발표회
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• pp.28.1-28
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• 1999