• The Plant Pathology Journal
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• 제38권1호
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• pp.46-51
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• 2022

Rice blast is the most destructive disease threatening stable rice production in rice-growing areas. Cultivation of disease-resistant rice cultivars is the most effective way to control rice blast disease. However, the rice blast resistance is easy to breakdown within years by blast fungus that continually changes to adapt to new cultivars. Therefore, it is important to continuously monitor the incidence of rice blast disease and race differentiation of rice blast fungus in fields. In 2020, a severe rice blast disease occurred nationwide in Korea. We evaluated the incidence of rice blast disease in Yeoju and compared the weather conditions at the periods of rice blast disease in 2019 and 2020. We investigated the races and avirulence genes of rice blast isolates in Yeoju to identify race diversity and genetic characteristics of the isolates. This study will provide empirical support for rice blast control and the breeding of blast-resistant rice cultivars.

• The Plant Pathology Journal
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• 제37권2호
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• pp.200-203
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• 2021

Rice blast caused by the filamentous fungus Magnaporthe oryzae, is arguably the most devastating rice disease worldwide. Development of a high-throughput and reliable field blast resistance evaluation system is essential for resistant germplasm screening, resistance genes identification and resistant varieties breeding. However, the occurrence of rice blast in paddy field is easily affected by various factors, particularly lack of sufficient inoculum, which always leads to the non-uniform occurrence and reduced disease severity. Here, we described a procedure for adequately inducing the occurrence of rice seedling blast in paddy field, which involves pretreatment of diseased straw, initiation of seedling blast for the first batch of spreader population, inducing the occurrence of the second batch of spreader population and test materials. This procedure enables uniform and consistent infection, which facilitates efficient and accurate assessment of seedling blast resistance for diverse rice materials.

• 한국농림기상학회지
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• 제25권4호
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• pp.245-257
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• 2023

우리나라 대표적인 식량 작물인 벼는 넓은 면적에서 장기간 재배되어 병해충에 대한 저항성이 낮아지고 있다. 대표적인 벼 질병 중 하나인 도열병이 대규모로 발생하면 수확량이 감소하여 조기에 병을 발견하고 방제를 하여야 한다. 하지만 농지 중심에서 도열병이 발생 하면 육안으로 병을 발견하기 어렵다. 드론을 이용한 작물 모니터링 기법은 생육 이상을 탐지하는데 유용하나 언제 발생할지 모르는 도열병 발생을 위해 빈번하게 촬영을 하는 것은 많은 인력과 비용이 소모된다. 본 연구의 목적은 드론, 위성과 같은 원격탐사 자료와 기상자료를 공동 활용하여 벼 도열병을 조기에 탐지하는 것이다. 위성영상은 벼 재배 필지를 추출하는데 유용하였다. 식생지수와 수분지수의 특성을 이용하여 관개가 된 논을 효과적으로 탐지하였다. 이후 기온, 상대습도, 강우일수 자료를 활용하여 벼 도열병 발생위험도를 계산하였다. 도열병 발생위험도가 증가하면 병이 발생할 가능성이 높아진다는 것을 의미하며, 해당 시점에 드론 관측을 수행하였다. 병이 발생한 지점, 병이 발생한 지점과 일반 벼가 혼재되어 있는 지점, 일반 벼 지점에서 분광반사도의 변화를 살펴보았으며, 갈색 병반을 가지는 도열병 특성상 적색과 근적외선 파장대에서 분광반사도의 변화가 급격한 것을 확인하였다. 도열병이 발생한 지점에서는 주변 지점에 비해 식생지수 값이 낮은 군집이 나타났으며, 시계열 드론 영상을 통해 해당 지점으로부터 벼 도열병 확산을 추적하였다. 최종적으로 수확 전 드론 영상을 활용하여 필지별 도열병 발생률에 대한 공간정보를 생산하였다.

• 식물병연구
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• 제7권2호
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• pp.102-106
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• 2001

2000년에 전국적으로 이삭누룩병이 발생한 포장의 비율은 7.5%이었으며, 지역별로는 충북이 13.7%로 가장 높았고 전남이 1.5%로 가장 낮았다. 벼 품종별로는 남천벼가 가장 감수성이었고 흑진주벼는 1999년과 2000년에 전혀 발생이 되지 않아 가장 저항성인 것으로 조사되었다. 이삭누룩병 약제방제 선발 시험결과 터부코나졸 수화제의 방제가는 83.0% 이상으로 가장 우수하였고, 훼림존 성분이 함유된 두 약제도 방제가가 60.9%∼75.9%로 나타났다. 남원 지역의 포장에서 이삭누룩병 발생이 높은 원인은 일조부족 및 강우량이 많아 발병이 조장된 것으로 분석되었다.

• Journal of Multimedia Information System
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• 제7권1호
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• pp.17-24
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• 2020

Rice (Oryza Sativa) is an important source of food for the people of our country, even though of world also .It is also considered as the staple food of our country and we know agriculture is the main source country's economy, hence the crop of Rice plays a vital role over it. For increasing the growth and production of rice crop, ground-breaking technique for the detection of any type of disease occurring in rice can be detected and categorization of rice crop diseases has been proposed in this paper. In this research paper, we perform comparison between two classifiers namely MDC and Bayes' classifiers Survey over different digital image processing techniques has been done for the detection of disease in rice crops. The proposed technique involves the samples of 200 digital images of diseased rice leaf images of five different types of rice crop diseases. The overall accuracy that we achieved by using Bayes' Classifiers and MDC are 69.358 percent and 81.06 percent respectively.

• Molecules and Cells
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• 제26권3호
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• pp.258-264
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• 2008

A rice diacylglycerol kinase (DGK) gene, OsBIDK1, which encodes a 499-amino acid protein, was cloned and characterized. OsBIDK1 contains a conserved DGK domain, consisting of a diacylglycerol kinase catalytic subdomain and a diacylglycerol kinase accessory subdomain. Expression of OsBIDK1 in rice seedlings was induced by treatment with benzothiadiazole (BTH), a chemical activator of the plant defense response, and by infection with Magnaporthe grisea, causal agent of blast disease. In BTH-treated rice seedlings, expression of OsBIDK1 was induced earlier and at a higher level than in water-treated control seedlings after inoculation with M. grisea. Transgenic tobacco plants that constitutively express the OsBIDK1 gene were generated and disease resistance assays showed that overexpression of OsBIDK1 in transgenic tobacco plants resulted in enhanced resistance against infection by tobacco mosaic virus and Phytophthora parasitica var. nicotianae. These results suggest that OsBIDK1 may play a role in disease resistance responses.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.83.1-83
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• 2003

Rice seedling disease is one of major problems in water-seeded rice. This disease is known to be caused by several pathogen such as Pythium, Achlya, and Fusarium species. However, seedling disease of rice in water-seeded rice in Korea is not extensively studied. Pythium species have been isolated from Seosan, Yeoju, Icheon areas using Pythium selective media and their pathogenicity was investigated. All of the Pythium isolates showed strong pathogencity causing seedling emergence reduction in water-seeded rice. Seedling emergence was reduced to 0∼9％ at 10 days after inoculation of 23 Pythium isolates compared to 60％ of noninoculated control in a growth chamber. However, Fusarium species did not cause seedling emergence reduction in water-seeded rice. In contrast, when no water added into water agar or soil, the pathogen caused seedling rot two weeks after planting. These results indicate that Pythium species is a cause of seedling disease in water-seeded cultivation areas in Korea.

• 식물병연구
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• 제18권4호
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• pp.399-401
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• 2012

발아현미 가공용 친환경 원료곡 생산에 적합한 벼 품종을 선발하기 위하여 농촌진흥청 국립식량과학원에서 개발된 주요 벼 품종을 친환경 재배단지(전남 곡성군)에서 3년간(2009-2011년) 유기재배를 실시하여 병해 및 수량 변화를 조사하였다. 삼광벼에서 벼 잎집무늬마름병과 도열병의 발병률은 대조구인 추청벼의 경우 보다 높게 나타났으나 고시히까리 보다는 현저히 낮게 발병하였다 또한 수확량은 추청벼, 고시히까리 보다 높게 나타났다. 특수미로 선발된 큰눈벼, 하이아미는 대조구인 추청벼, 고시히까리와 비슷한 발병률과 수확량을 보였다. 결론적으로 삼광벼, 큰눈벼, 하이아미는 곡성지방에서 친환경 재배를 하였을 경우 발병률 및 수량변동이 크게 변하지 않을 것으로 생각되며 특히 발아현미 원료곡으로 친환경 유기재배에 적합한 벼 품종으로서 선발 할 수 있을 것으로 판단된다.

• 식물병연구
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• 제13권1호
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• pp.20-23
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• 2007

2002년부터 2005년까지 4년간 벼 흰잎마름병 초발병 조사결과 2002년보다 초발병일이 20$\sim$30일 이상 빨라지고 있음을 확인하였다. 벼 흰잎마름병 발병시기 및 병반면적율에 따라 수량이 감소하였는데 병반면적률이 10% 이하에서는 피해가 적었으나, 병반적율이 증가함에 따라서 수량감소가 점점 많아졌고, 25% 이상일 때부터 수량감소 및 현미천립중 등에서 현저히 낮아지고 병반면적율이 50% 이상이고 유수형성기 발병시 수량 29%, 현미천립중 2.3g, 현미완전립률 18%까지 감소되었다. 밥맛의 기준이 되는 식미치인 점도에서도 병반면적율이 증가함에 따라 낮은 식미치를 보였다.

• 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.