• 식물병연구
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• 제9권1호
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• pp.52-56
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• 2003

전남 나주의 벼 누른오갈병이 발생한 담수직파 포장에서 일미벼를 대상으로 병 발생이 벼 생육에 미치는 영향을 조사하고 품종저항성 검정을 수행하였다. 누른오갈병 발생시 잎에는 퇴록반점이 나타나고 엽장이 짧아지며 벼의 생육이 진행되면서 줄기의 절간신장이 제대로 이루어지지 않아 마디사이가 기형적으로 자라고 출수가 안되거나 기형이삭이 되는 증상을 보였다. 벼 누른오갈병 이병시 초장이 짧아졌고, 분얼수는 최고분얼기 전에 발병주가 적었지만 그 이후에는 발병주가 많았다. 마디수는 발병줄기가 건전줄기에 비해 많은 반면에 마디길이는 짧았다. 발병정도가 심할 수록 단위면적당 이삭수가 적고 등숙율이 낮아 수량이 크게 감소하였다. 유묘를 대상으로 품종 저항성 검정을 실시한 결과, 동진벼, 계화벼가 벼 누른오갈병에 대해서 저항성이었다.

• 한국식물병리학회지
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• 제1권3호
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• pp.165-168
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• 1985

흰가루병에 대하여 감수성인 봄보리품종 Peruvian과 성체식물 저상성품종 Asse의 건전잎과 감염잎에 함유되어 있는 에탄올가용성 아미노산을 분석하였다. 접종1일 후에는 이들 두 품종의 제1엽내의 아미노산 함량은 건전잎과 비슷한 수준이었다. 포자형성 동안 Asse보다 Peruvian에서 아미노산의 증가에 뚜렷하였다. 감염된 제1엽, 제5엽에서 아미노산 함량은 엽당 병반수가 많을수록 증가하였고, 감수성 품종 Peruvian의 감염잎이 Asse보다 아미노산 함량이 더 높았다.

• The Plant Pathology Journal
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• 제24권1호
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• pp.31-35
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• 2008

The presence of Chrysanthemum stunt viroid (CSVd) in seed and pollen of diseased chrysanthemum was demonstrated. In seeds infected male parent from crosses in May, CSVd was transmitted to 6.7% of the progeny seedlings, whereas if the female parent was infected, CSVd transmission rate was between 46.9 and 75.7%. A relatively high incidence of 94.4 to 96.0% seed transmission occurred when both parents were infected. In seeds infected male parent from crosses in December, no progeny seedlings were infected with CSVd, whereas if the female parent did, CSVd transmission rate was 1.5%. When both parents were infected, 6.9% seed transmission was occurred. The seed transmission rate depended on the temperature when the crosses were made. CSVd was not detected in the non-infected female parent pollinated with infected pollen but was transmitted to the progenies. This is the first report of seed-borne transmission of CSVd in chrysanthemum.

• The Plant Pathology Journal
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• 제18권3호
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• pp.126-129
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• 2002

Infected sweet potato (Ipomoea batatas) showing symptoms of sunken veins, stunting, mosaic, and mottling were collected from Gimje, Cochang, Iksan, and Haenam provinces in Korea. Electron microscopic (EM) observation of the infected tissue revealed rod and filamentous rod type virus particles of various lengths. Western blot analysis of the protein samples extracted from infected sweet potato and partially purified virus identified the isolates as Sweet potato feathery motile virus (SPFMV), Sweet potato latent virus (SwPLV), and Sweet potato chlorotic stint virus (SPCSV). Sweet potatoes were occasionally infected with more than one of these viruses. This is the first report of SwPLV and SPCSV in Korea.

• 한국식물병리학회지
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• 제13권4호
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• pp.239-243
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• 1997

1990년 8월 충북 보은의 참깨 밭에서 전형적인 엽화병(葉化病; phyllody disease)이 발생하였다. 병징은 꽃이 잎처럼 녹색으로 변하고, 이병엽은 정상엽보다 작고 잔가지가 마치 빗자루 모양으로 총생하였고 개화 및 결실이 되지 않았다. 투과 전자현미경으로 병든 잎의 사관요소에서 phytoplasma가 존재하는 것을 확인하였다. 병든 잔가지에서 추출한 DNA를 중합효소 연쇄반응으로 분석한 결과 대추나무 빗자루병에 걸린 나무에서 증폭되는 DNA와 같은 크기의 band가 관찰되었다. 따라서 위의 시료는 phytoplasma 벙으로 확인 되었으며 참깨 엽화병으로 명명하였다. 또한 참깨 엽화병을 일으키는 phytoplasma와 대추 나무 빗자루병 phytoplasma를 PCR 증폭 및 제한효소로 절단하여 분석한 결과 이들은 서로 다른 그룹이라는 것을 알 수 있었다.

• Journal of Veterinary Science
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• 제22권2호
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• pp.26.1-26.6
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• 2021

Fourteen African swine fever (ASF) outbreaks occurred in the pig farms in the northwestern region of South Korea, near the border with North Korea, from September 16, 2019 to October 9, 2019. Active and passive surveillance on the ASF-infected farms indicated that the infection was limited only to pigsties where the infected pigs were detected on the farm for the first time before further transmission to other pigsties and farms. This early detection could be one of the pivotal factors for the prompt eradication of ASF in domestic pig farms within 1 month in the northwestern region of South Korea.

• Journal of Biosystems Engineering
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• 제33권6호
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• pp.446-452
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• 2008

Machine vision system was used for analyzing leaf color disorders of tomato plants in a greenhouse. From the day when a few leave of tomato plants had started to wither, a series of images were captured by 4 times during 14 days. Among several color image spaces, Saturation frame in HSI color space was adequate to eliminate a background and Hue frame was good to detect infected disease area and tomato fruits. The processed image ($G{\sqcup}b^*$ image) by OR operation between G frame in RGB color space and $b^*$ frame in $La^*b^*$ color space was useful for image segmentation of a plant canopy area. This study calculated a ratio of the infected area to the plant canopy and manually analyzed leaf color disorders through an image segmentation for Hue frame of a tomato plant image. For automatically analyzing plant leave disease, this study selected twenty-seven color patches on the calibration bars as the corresponding to leaf color disorders. These selected color patches could represent 97% of the infected area analyzed by the manual method. Using only ten color patches among twenty-seven ones could represent over 85% of the infected area. This paper showed a proposed machine vision system may be effective for evaluating various leaf color disorders of plants growing in a greenhouse.

• The Plant Pathology Journal
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• 제39권2호
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• pp.207-219
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• 2023

Soft rot is a widespread, catastrophic disease caused by Pectobacterium carotovorum subsp. carotovorum (Pcc) that severely damages the production of Amorphophallus spp. This study evaluated the rhizosphere bacterial and fungal communities in Pcc-infected and uninfected plants of two species of Amorphophallus, A. muelleri and A. konjac. Principal component analysis showed that the samples formed different clusters according to the Pcc infection status, indicating that Pcc infection can cause a large number of changes in the bacterial and fungal communities in the Amorphophallus spp. rhizosphere soil. However, the response mechanisms of A. muelleri and A. konjac are different. There was little difference in the overall microbial species composition among the four treatments, but the relative abundances of core microbiome members were significantly different. The relative abundances of Actinobacteria, Chloroflexi, Acidobacteria, Firmicutes, Bacillus, and Lysobacter were lower in infected A. konjac plants than in healthy plants; in contrast, those of infected A. muelleri plants were higher than those in healthy plants. For fungi, the relative abundances of Ascomycota and Fusarium in the rhizosphere of infected A. konjac plants were significantly higher than those of healthy plants, but those of infected A. muelleri plants were lower than those of healthy plants. The relative abundance of beneficial Penicillium fungi was lower in infected A. konjac plants than in healthy plants, and that of infected A. muelleri plants was higher than that of healthy plants. These findings can provide theoretical references for further functional research and utilization of Amorphophallus spp. rhizosphere microbial communities in the future.

• 한국식물병리학회지
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• 제14권5호
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• pp.545-547
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• 1998

Scab disease of Aralia elata (Miq.) Seemann occurred severely in Kangwon province, Korea. First, brown spots were formed on leaves and enlarged along vein. The infected leaves including petiole and midrib were twisted forming scab and died eventually. Also the disease infected twigs and trunks of the tree forming scab. Conidia, ascospores and asci developed in locule were observed in the infected tissue. The causal organism of the scab disease of Araliae elata was isolated and identified as Elsinoe araliae Yamamoto (imperfect stage: Sphaceloma araliae Jenkins) based on the morphological and cultural characteristics, and pathogenic test.

• The Plant Pathology Journal
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• 제35권5호
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• pp.521-529
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• 2019

Tomato yellow leaf curl China virus is a species of the widespread geminiviruses. The infection of Nicotiana benthamiana by Tomato yellow leaf curl China virus (TYLCCNV) causes a reduction in photosynthetic activity, which is part of the viral symptoms. ${\beta}C1$ is a viral factor encoded by the betasatellite DNA ($DNA{\beta}$) accompanying TYLCCNV. It is a major viral pathogenicity factor of TYLCCNV. To elucidate the effect of ${\beta}C1$ on plants' photosynthesis, we measured the relative chlorophyll (Chl) content and Chl fluorescence in TY-LCCNV-infected and ${\beta}C1$ transgenic N. benthamiana plants. The results showed that Chl content is reduced in TYLCCNV A-infected, TYLCCNV A plus $DNA{\beta}$ (TYLCCNV A + ${\beta}$)-infected and ${\beta}C1$ transgenic plants. Further, changes in Chl fluorescence parameters, such as electron transport rate, $F_v/F_m$, NPQ, and qP, revealed that photosynthetic efficiency is compromised in the aforementioned N. benthamiana plants. The presense of ${\beta}C1$ aggravated the decrease of Chl content and photosynthetic efficiency during viral infection. Additionally, the real-time quantitative PCR analysis of oxygen evolving complex genes in photosystem II, such as PsbO, PsbP, PsbQ, and PsbR, showed a significant reduction of the relative expression of these genes at the late stage of TYLCCNV A + ${\beta}$ infection and at the vegetative stage of ${\beta}C1$ transgenic N. benthamiana plants. In summary, this study revealed the pathogenicity of TYLCCNV in photosynthesis and disclosed the effect of ${\beta}C1$ in exacerbating the damage in photosynthesis efficiency by TYLCCNV infection.