• 한국유기농업학회지
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• 제24권4호
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• pp.919-929
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• 2016

본 연구는 비닐하우스에서 오이재배 시 유기농업자재(석회보르도액, 황토유황합제)와 순지르기가 노균병 발병에 미치는 영향을 알아보기 위하여 수행되었다. 자재는 석회보르도액과 황토유황합제를 사용하였으며 석회보르도액은 최적농도를 규명하기 위해 석회와 황산구리의 배합비율을 조절하여 5가지를 만들어서 노균병 발생 후 치료위주로 처리하였다. 본 실험을 수행한 결과, 자재 중에서는 4-6식 석회보르도액이 가장 효율적이라는 것을 알 수 있었고 황토유황합제는 석회보르도액보다 효과가 떨어졌으나 병에 대한 억제효과가 있었다. 순지르기가 병 발생억제에 미치는 영향에 있어서는 순지르기를 한 것이 제거하지 않은 것 보다 병 발생이 56.3% 억제되었다. 순지르기시기에 따른 오이 노균병 발생정도는 감수성 품종인 미소백다다기의 경우 순지르기를 할수록 병 발생이 감소되었고 저항성 품종인 흑룡삼척의 경우에는 병 발생이 적어 차이를 보이지 않았다. 또한 유기농업자재와 순지르기를 병행처리 한 결과, 자재와 순지르기 처리를 병행 처리한 처리구가 모두 병반면적률이 낮았으며 그 중에서도 석회보르도액 4-6식이 가장 낮은 병반면적률을 나타내었다. 본 연구를 통해 순지르기가 오이 노균병 억제에 효과가 있고 자재와 함께 병행하여 처리하였을 때 더 효과가 높았음을 알 수 있었다.

• 식물병연구
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• 제14권2호
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• pp.138-141
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• 2008

경상북도 오이 주산단지인 상주와 군위지역의 바이러스 병 발생을 조사한 결과 포장 발생율은 $55.0{\sim}88.6%$였으며, 상주지역이 군위보다 약간 높게 나타났다. 바이러스 발병 포장의 이병주율은 2006년 상주 지역에서 평균 25.6%로 매우 높게 나타났으며, 발생범위는 최소 1.5%에서 최대 90%로 농가별로 편차가 매우 심하였다. 포장에서 바이러스 증상으로 관찰되는 시료 217점을 RT-PCR을 이용하여 바이러스 종류를 분석한 결과 ZYMV가 85% 이상으로 가장 많이 검출되어 오이에 피해를 주는 주요 바이러스로 나타났다. ZYMV에 감염된 오이는 잎에 황화 및 심한 모자이크 증상이 나타났으며 일부 과일은 곡과 증상과 함께 표면이 울퉁불퉁하게 나타났다.

• Mycobiology
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• 제47권3호
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• pp.308-318
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• 2019

Bio-sulfur can be produced in the process of desulfurization from a landfill and collected by some microorganism such as Thiobacillus sp. as a sulfur element. In order to investigate practical use of bio-sulfur as an agent for controlling plant disease, in vitro antifungal activity of bio-sulfur was tested against Colletotrichum orbiculare known to cause cucumber anthracnose. Efficacy of bio-sulfur for suppressing anthracnose disease was also evaluated in vivo using cucumber leaves. Mycelial growth of C. orbiculare on medium containing bio-sulfur was inhibited. Disease severity of cucumber leaves pre-treated with bio-sulfur was significantly decreased compared to that of untreated ones. To illustrate how bio-sulfur could suppress anthracnose disease, structures of cucumber leaves infected with C. orbiculare were observed under a fluorescent microscope and a scanning electron microscope (SEM). Cucumber leaves pre-treated with bio-sulfur showed a low rate of appressorium formation whereas untreated ones showed abundant appressoria. Shrunk fungal hyphae were mostly observed on bio-sulfur-pretreated leaves by SEM. Similar results were observed on leaves pre-treated with a commercial fungicide Benomyl(R). These results suggest that inhibition of appressorium formation of C. orbiculare by bio-sulfur may contribute to its suppression of cucumber anthracnose.

• The Plant Pathology Journal
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• 제22권2호
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• pp.147-151
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• 2006

Disease incidences of cucumber virus diseases in Jeonnam province were 52.5%, 16.1%, 35.2%, and 50.9% in 1999, 2000, 2001, and 2002, respectively. Rod- and flexuous rod-shaped virus particles were observed with the frequencies of 63.2% and 10.5%, respectively from the samples collected in 1999 under EM observation. Rod-shaped virus particles are considered as tobamovirus while flexuous rod shaped particles are considered as potyviruses. To further confirm their nature, total of 312 diseased virus samples were collected from 2000 to 2002, and tested by RT-PCR. Disease incidences of tobamoviruses including Cucumber green mottle mosaic virus and Kyuri green mottle mosaic virus were 48.7% and 3.8%, respectively while those of potyviruses including Zucchini yellow mosaic virus, Papaya ringspot virus, and Watermelon mosaic virus were 15.7%, 9.3%, and 5.1%, respectively. Interestingly, Cucumber mosaic virus was hardly detected. About 5.8% of tested samples were infected with more than one virus. Tobamovirus infection was consistently observed from September to December regardless of planting time, whereas infection of potyviruses was observed in many cucumber cultivating areas where it was planted in September and October.

• 식물병연구
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• 제12권3호
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• pp.231-234
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• 2006

오이 흰가루병(Sphaerotheca fusca)이 수량에 미치는 영향을 구명하고자 오이 잎 제거를 통한 시뮬레이션으로 적정 잎수에 관한 모의시험 및 발병도 조절에 따른 흰가루병이 수량에 미치는 영향과 경제적 피해허용수준을 검토하였다. 오이 잎 제거 수준과 수량과의 시뮬레이션 결과 봄작기에서는 오이 잎 수를 10매, 가을작기에서는 13매 정도를 유지하면 표준방제구와 큰 차이가 없었다. 오이 흰가루병 발병도가 증가할수록 수량이 감소하였으며, 특히 상품성 수량의 감소폭이 전체 수량의 감소폭보다 더 커서 상품성 수량에 큰 영향을 미쳤다. 오이 흰가루병 발병도와 수량과의 회귀식은 Y=-57.237x+6143.1, $R^2=0.9628$로 방제비용을 감안하여 수량 3% 지점의 발병도 17.6%를 경제적 피해 허용 수준으로 설정하였다. 오이 흰가루병 방제적기는 경제적 피해 허용수준과 시뮬레이션 결과를 종합할 때 흰가루병으로 발병된 잎이 $1{\sim}2$장일 때 방제를 시작해야 하는 시점으로 생각된다.

• The Plant Pathology Journal
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• 제27권1호
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• pp.78-84
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• 2011

Antagonistic rhizobacteria, more specifically fluorescent pseudomonads and certain species of Bacillus, are known as biocontrol agents of fungal root diseases of agronomic crops. In this study, 144 bacteria were isolated from cucumber rhizosphere and screened as potential biological control agents against Phytophthora drechsleri, the causal agent of cucumber root rot, in vitro condition. Non-volatile compounds of 23 isolates showed noticeable inhibition zone (> 30%) against P. drechsleri, whereas volatile compounds of 7 isolates could prevent more than 30% of the mycelial growth of the fungus. All promising isolates, except of Pseudomonas flourescens V69, promoted significantly plant growth under in vitro condition. P. flourescens CV69 and V11 exhibited the highest colonization on the root. Results of the greenhouse studies showed that a reduction in disease incidence by use of some strains, and particularly use of strains CV6 and V11 as a soil treatment, exhibited a reduction in disease incidence so that suppressed disease by 85.71 and 69.39% respectively. Pseudomonas flourescens CV6 significantly suppressed disease in comparison to Ridomil fungicide. The use of mixture bacterial strains in the soil inoculated by the fungus resulting in falling down the most of the plants which didn't show significant difference with infected control soils without bacteria.

• The Plant Pathology Journal
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• 제25권4호
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• pp.333-343
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• 2009

Here, we show that an endophytic bacterial strain, Enterobacter asburiae B1 exhibits the ability to elicit ISR in cucumber, tobacco and Arabidopsis thaliana. This indicates that strain B1 has a widespread ability to elicit ISR on various host plants. In this study, E. asburiae strain B1 did not show antifungal activity against tested major fungal pathogens, Colletotrichum orbiculare, Botrytis cinerea, Phytophthora capsici, Rhizoctonia solani, and Fusarium oxysporum. Moreover, the siderophore production by E. asburiae strain B1 was observed under in vitro condition. In greenhouse experiments, the root treatment of strain B1 significantly reduced disease severity of cucumber anthracnose caused by fungal pathogen C. orbiculare compared to nontreated control plants. By root treatment of strain B1 more than 50% disease control against anthracnose on cucumber was observed in all greenhouse experiments. Simultaneously, under the greenhouse condition, the soil drench of strain B1 and a chemical inducer benzothiadiazole (BTH) to tobacco plants induced GUS activity which is linked with activation of PR promoter gene. Furthermore, in Arabidopsis thaliana plants the soil drench of strain B1 induced the defense gene expression of PR1 and PDF1.2 related to salicylic acid and jasmonic acid/ethylene signaling pathways, respectively. In this study, for the main focus on root colonization by strain B1 associated with defense responses, bacterial cells of strain B1 was tagged with the gfp gene encoding the green fluorescent protein in order to determine the colonization pattern of strain B1 in cucumber. The gfp-tagged B1 cells were found on root surface and internal colonization in root, stem, and leaf. In addition to this, the scanning electron microscopy observation showed that E. asburiae strain B1 was able to colonized cucumber root surface.

• 한국멀티미디어학회논문지
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• 제25권11호
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• pp.1653-1671
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• 2022

Crop diseases affect crop production, more than 30 billion USD globally. We proposed a classification study of crop species and diseases using deep learning algorithms for corn, cucumber, pepper, and strawberry. Our study has three steps of species classification, disease detection, and disease classification, which is noteworthy for using captured images without additional processes. We designed deep learning approach of deep learning convolutional neural networks based on Mask R-CNN model to classify crop species. Inception and Resnet models were presented for disease detection and classification sequentially. For classification, we trained Mask R-CNN network and achieved loss value of 0.72 for crop species classification and segmentation. For disease detection, InceptionV3 and ResNet101-V2 models were trained for nodes of crop species on 1,500 images of normal and diseased labels, resulting in the accuracies of 0.984, 0.969, 0.956, and 0.962 for corn, cucumber, pepper, and strawberry by InceptionV3 model with higher accuracy and AUC. For disease classification, InceptionV3 and ResNet 101-V2 models were trained for nodes of crop species on 1,500 images of diseased label, resulting in the accuracies of 0.995 and 0.992 for corn and cucumber by ResNet101 with higher accuracy and AUC whereas 0.940 and 0.988 for pepper and strawberry by Inception.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1997년도 Proceedings of special lectures on Recent Research Trend of Plant Pathology
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• pp.47-55
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• 1997

Plant growth promoting fungi(PGPF) obtained from zoysiagrass rhizosphere offer dual advantages - induse systemic disease resistance response in cucumber to C. orbiculare infection and cause enhancement of plant growth and increase yield. PGPF protected plants either by colonizing roots or by their metabolites. PGPF offer an advantage by protecting plants for more than 9 weeks and 6 week in the greenhouse and field. PGPF-induced plants limited pathogen spore germination and decreased the number of infection hyphae on the leaf, and increased lignification at places of attempted pathogen infection, thus reducing the pathogen spread. PGPF elicited increased activities of chitinascs, glucanases, peroxidase, polyphenol oxidase, and phenylalanine ammonia lyase to C. orbiculare infection in cucumber plants. The role of PGPF in elevating cucumber defense response to pathogen infection suggests potential application of PGPF as biological control agents.

• 식물병과 농업
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• 제5권1호
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• pp.14-19
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• 1999

Cucumber mosaic cucumovirus (CMV) is an isometric plant virus with functionally divided genomic RNAs and a broad host range. RNA 1 and RNA 2 each encode one protein, both of which are essential for replication. RNA 3 encodes the viral coat protein and an additional protein thought to be involved in potentiating the cell-to-cell movement of the virus. Functions of the RNAs have been confirmed using a pseudorecombinant virus constructed with infectious cDNA-derived transcripts of the RNAs. Generally, CMV produces different symptoms in various host plants depending on the virus strains. In this mini-review, we describe the potential role of the genes associated with symptom expression of CMV RNAs.