• The Plant Pathology Journal
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• 제33권2호
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• pp.184-192
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• 2017

Tylenchulus semipenetrans is an important and widespread plant-parasitic nematode of citrus worldwide and can cause citrus slow decline disease leading to significant reduction in tree growth and yield. Rapid and accurate detection of T. semipenetrans in soil is important for the disease forecasting and management. In this study, a loop-mediated isothermal amplification (LAMP) assay was developed to detect T. semipenetrans using DNA extracted from soil. A set of five primers was designed from the internal transcribed spacer region (ITS1) of rDNA, and was highly specific to T. semipenetrans. The LAMP reaction was performed at $63^{\circ}C$ for 60 min. The LAMP product was visualized directly in one reaction tube by adding SYBR Green I. The detection limit of the LAMP assay was $10^{-2}J2/0.5g$ of soil, which was 10 times more sensitive than conventional PCR ($10^{-1}J2/0.5g$ of soil). Examination of 24 field soil samples revealed that the LAMP assay was applicable to a range of soils infested naturally with T. semipenetrans, and the total assay time was less than 2.5 h. These results indicated that the developed LAMP assay is a simple, rapid, sensitive, specific and accurate technique for detection of T. semipenetrans in field soil, and contributes to the effective management of citrus slow decline disease.

• Journal of Multimedia Information System
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• 제4권4호
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• pp.233-238
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• 2017

Automatic identification of disease in plants from their leaves is one of the most challenging task to researchers. Diseases among plants degrade their performance and results into a huge reduction of agricultural products. Therefore, early and accurate diagnosis of such disease is of the utmost importance. The advancement in deep Convolutional Neural Network (CNN) has change the way of processing images as compared to traditional image processing techniques. Deep learning architectures are composed of multiple processing layers that learn the representations of data with multiple levels of abstraction. Therefore, proved highly effective in comparison to many state-of-the-art works. In this paper, we present a plant disease identification methodology from their leaves using deep CNNs. For this, we have adopted GoogLeNet that is considered a powerful architecture of deep learning to identify the disease types. Transfer learning has been used to fine tune the pre-trained model. An accuracy of 85.04% has been recorded in the identification of four disease class in Apple plant leaves. Finally, a comparison with other models has been performed to show the effectiveness of the approach.

• 한국초지조사료학회지
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• 제9권3호
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• pp.174-178
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• 1989

The investigation was carried out to identify the main pathogen infected with sheath blight in corn plant during 1986-1987. The main fungi of sheath blight isolated from corn plant was identified as Rhizoctonia sobni. Sheath blight in corn plant was first found in early July and infected extremely from late July to end August. Severe sheath blight disease was observed in Gyeongido (Yeoju and Suweon) and Jeonnam (Kwangju) area. The rate of attack was associatied with management and cultural environments of corn plant. Dense planting increased sheath blight, but application of cattle compost reduced the rate of infection. A positive correlation was found between infection rate of shealth blight and concentration of soluble carbohydrate in corn plant (r=0.96). The varieties of Jinjuok, Suweon 83, Suweon 87, Suweon 89, P.3055, P.3160, DK689 and XCG 51 showed remarkable tolerance to sheath blight disease.

• 대한수의학회지
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• 제58권3호
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• pp.125-129
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• 2018

We investigated the prevalence of canine brucellosis in companion and stray dogs between March 2015 and December 2016 and determined the disease characteristics based on the geographic distribution, sex and age of the dogs in South Korea. We conducted a large-scale survey using serological and bacteriological tests. Samples were collected from 2,394 dogs (1,825 companions and 569 strays). Thirty (1.3%) samples were positive for Brucella canis antibodies including 16 (0.9%) from companion dogs and 14 (2.5%) from stray dogs. Two (1.0%) of the 196 samples cultured from the stray dogs were positive. When compared with male dogs, the female companion and stray dogs had a significantly higher prevalence of brucellosis. Moreover, the prevalence of canine brucellosis was significantly higher in stray dogs older than 6 years and the prevalence of the disease in companion dogs was highest in Incheon (2.1%) and Jeolla (2.1%) provinces. Stray dogs from the Daejeon metropolitan area had the highest prevalence of brucellosis (7.9%). National control measures for canine brucellosis have not previously been implemented. Our findings suggest that appropriate screening tests and control measures are necessary to improve the health of dogs and to protect public health in Korea, particularly with the rapid growth of the companion animal industry.

• Journal of Veterinary Science
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• 제22권2호
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• pp.24.1-24.16
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• 2021

Background: Bovine tuberculosis (TB) is caused by Mycobacterium bovis, a well-known cause of zoonotic tuberculosis in cattle and deer, and has been investigated in many physiological and molecular studies. However, detailed genome-level studies of M. bovis have not been performed in Korea. Objectives: To survey whole genome-wide single-nucleotide polymorphism (SNP) variants in Korean M. bovis field isolates and to define M. bovis groups in Korea by comparing SNP typing with spoligotyping and variable number tandem repeat typing. Methods: A total of 46 M. bovis field isolates, isolated from laryngopharyngeal lymph nodes and lungs of Korean cattle, wild boar, and Korean water deer, were used to identify SNPs by performing whole-genome sequencing. SNP sites were confirmed via polymerase chain reaction using 87 primer pairs. Results: We identified 34 SNP sites with different frequencies across M. bovis isolates, and performed SNP typing and epidemiological analysis, which divided the 46 field isolates into 16 subtypes. Conclusions: Through SNP analysis, detailed differences in samples with identical spoligotypes could be detected. SNP analysis is, therefore, a useful epidemiological tracing tool that could enable better management of bovine TB, thus preventing further outbreaks and reducing the impact of this disease.

• 식물병연구
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• 제29권4호
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• pp.363-376
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• 2023

검은무늬병은 세계적으로 재배되는 십자화과 작물을 황폐화시키고 있으며, 브로콜리, 배추, 케일, 무, 유채 등의 생산에 경제적인 손실을 가져왔다. 십자화과 작물의 검은무늬병은 A. brassicae, A. brassicicola, A. raphani 등을 포함하는 다수의 Alternaria 종에 의하여 발생하며 이러한 병원균들은 감염된 종자나 매개충에 의하여 전반된다. 본 총설에서는 검은무늬병에 대한 십자화과 작물의 병 저항성 형질을 발굴하기 위한 그 동안의 노력을 보여주었다. 병 저항성을 위한 유전 자원이 십자화과 작물의 근연 야생종으로부터 조사되었으며, 십자화과 작물의 상이한 품종들이 다른 접종 조건에서 선별되었다. 검은무늬병 저항성 작물의 개발을 위하여 다양한 식물 방어 관련 유전자들을 이용한 십자화과 작물의 형질 전환이 이루어지기도 하였다. β-Amino-n-butyric acid나 멜라토닌과 같은 화학 물질을 전처리하여 활성화된 식물 면역이 십자화과 작물의 검은무늬병을 줄이기 위하여 제안되었다. 검은무늬병 저항성 형질은 다른 서식지에서 유래한 모델 식물 Arabidopsis 생태형들에서도 평가되었다. 야생형 Arabidopsis와는 상이한 병 저항성을 보이는 식물 면역 관련 돌연변이체들은 십자화과 작물에서 검은무늬병을 관리하는 데에 가치있는 정보를 제공하였다. 특히 이러한 돌연변이체에서 변동된 산화-환원 조절과 항산화 반응에 대하여 본 총설에서 논하였다.

• Journal of Plant Biotechnology
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• 제4권1호
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• pp.1-6
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• 2002

Plants have developed a sophisticated battery of defence responses to protect themselves against attempted pathogen ingress. Manipulation of these defence mechanisms may provide significant opportunities for crop improvement. While plant resistance genes have had a long service history in plant breeding, they possess significant limitations. Recent advances are now providing significant insights into strategies designed to increase the field durability of this class of genes. Hypersensitive cell death is a common feature underlying the deployment of plant defence responses against biographic pathogens. In contrast, necrotrophic pathogens actively kill plant cells. Recently, transgenic plants have been developed that either promote or suppress cell death, providing resistance against either biotrophic or necrotrophic pathogens respectively. Methyl-jasmonate is a key signalling molecule in the establishment of resistance against some fungal pathogens. Increasing the concentration of this molecule in plant cells has been shown to increase resistance against Botrytis cineria, without significantly imparting plant growth or development. Due to the multifarious infection strategies employed by plant pathogens, how-ever, it is unlikely a single commercial product will prove a panacea for global disease control. Future stategies will more likely entail an integrated disease management approach.

• The Plant Pathology Journal
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• 제36권5호
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• pp.406-417
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• 2020

Early warning services for crop diseases are valuable when they provide timely forecasts that farmers can utilize to inform their disease management decisions. In South Korea, collaborative disease controls that utilize unmanned aerial vehicles are commonly performed for most rice paddies. However, such controls could benefit from seasonal disease early warnings with a lead time of a few months. As a first step to establish a seasonal disease early warning service using seasonal climate forecasts, we developed the EPIRICE Daily Risk Model for rice blast by extracting and modifying the core infection algorithms of the EPIRICE model. The daily risk scores generated by the EPIRICE Daily Risk Model were successfully converted into a realistic and measurable disease value through statistical analyses with 13 rice blast incidence datasets, and subsequently validated using the data from another rice blast experiment conducted in Icheon, South Korea, from 1974 to 2000. The sensitivity of the model to air temperature, relative humidity, and precipitation input variables was examined, and the relative humidity resulted in the most sensitive response from the model. Overall, our results indicate that the EPIRICE Daily Risk Model can be used to produce potential disease risk predictions for the seasonal disease early warning service.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.9-12
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• 2003

Clubroot disease of curcifer crops caused by Plasmodiophora brassicae had been first reported in 1920 in Korea, and maintained mild occurrence until 1980s. Since 1990s the disease has become severe in alpine areas of Kyonggi and Kangwon, gradually spread to plain fields throughout the country, and remains as the greatest limiting factor for its production. Researches on the disease has begun in late 1990s in our laboratory after experiencing severe epidemics. Survey of occurrence and etiological and ecological studies have been carried out, particularly, on the pathogen physiology, race identification, quantification of soil pathogen population, host spectrum of the pathogen, and control measures.(중략)

• Mycobiology
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• 제41권2호
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• pp.108-111
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• 2013

The use of a microorganism, or its secretions, to prevent plant disease offers an attractive alternative or supplement to synthetic fungicides for the management of plant disease without the negative effects of chemical control mechanisms. During a screening for microorganisms with the potential to be used as microbial fungicides, Bacillus sp. BS061 was isolated from a plant leaf. The strain BS061 potently inhibited the mycelial growth of Botrytis cinerea, and significantly reduced disease incidence of powdery mildew in cucumber and strawberry. We also found that the culture filtrate of BS061 inhibited the mycelial growth of various plant pathogens.