• 한국식물병리학회지
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• 제13권2호
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• pp.73-78
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• 1997

A virus was purified from Korean cactus (Chamaeaereus silverstrii f. Variegata Hort) showing necrotic spots and its biophysicochemical properties were examined. The typical necrotic spots were observed on healthy looking cactus inoculated with the purified virus and the various symptoms from necrotic spots to systemic were observed on 17 species of test plats used, which suggests that the purified virus has the normal infectivity and wide host range. Ultraviolet absorption scanning analysis revealed that the viral preparation had the typical curve with shoulder at 290 nm and its ratio of absorbances at 260 nm to 280 nm and extinction coefficient was 1.156 and 2.86, respectively. The virus represented one distinct and homogeneous band and molecular weight of viral coat protein was determined to 17, 000 Dalton by SDS-PAGE. The virus revealed rod-shaped virion (325$\times$20 nm) by electron microscopy. Based on these results, it has been thought that the virus purified in this study is the pathogenic agents causing necrotic spot symptom on Korean cacuts and one of the member of tobamovirus family.

• 한국응용곤충학회지
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• 제23권4호
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• pp.203-208
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• 1984

잎담배 4품종 (NC2326, NC95, NC744, Havana)과 2종의 식물 (Nicotiana repanda Wild., Physalis floridana Rydb.)을 이용하여 감자 또는 잎담배에서 분리된 10가지의 감자바이러스 Y (PVY) 계통 판별을 시도하였다. 10가지의 PVY 계통들을 이 식물들에 접종했을 때 괴저, 엽맥녹대 또는 mottling, 무병징등을 나타내면서 서로 다른 기주반응을 보여 쉽게 구분할 수 있었다. 조사된 계통들 중에 PVY-VN, PVY-N, PVY-NSNR, PVY-Chile 및 PVY-Argentina 등은 잎담배 품종 NC2326에서 괴저병징을 나타냈으며 이외 계통들은 엽맥녹대 또는 mottling 병징을 나타냈다. NC95에서는 PVY-MSMR에 의해 괴저병징을 이 외 계통들에 의해서는 엽맥녹대 또는 mottling 병징을 나타냈다. Havana에서는 PVY-NSNR, PVY-MSNR, PVY-VB 등에 의해 nettling 병징을, PVY-Chile 및 PVY-Argentina에 의해 괴저병징을 나타냈으나 이 외의 계통들에 의해서는 병징이 나타나지 않았다. NC744에서는 PVY-MSNR, PVY-MSMR에 의해 mottling 병징을, PVY-Chi 및 PVY-Argentina에 의해 괴저병징을 나타냈으며 이 외의 계통들에 의해서는 병징을 나타내지 않았다. N. repanda에서는 PVY-Argentina에 의해 괴저 반응을, PVY-VN 및 PVY-C에 의해서는 병징을 나타내지 않았으며 이 외의 계통들에 의해서는 mottling 병징을 나타냈다.

• 식물병연구
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• 제12권3호
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• pp.221-225
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• 2006

용담에서 전형적인 모자이크 증상을 나타낸 바이러스 이병주 및 황화증상을 보이는 식물체를 채집하였다. 이들 중, 모자이크 증상의 잎을 접종하여 전신감염된 Nicotiana benthamiana로부터의 접종원을 동부의 초생엽에 접종하였을 때, 2가지 형태의 괴사 국부병반이 형성되었다. 즉 하나는 작은 크기 pinpoint 형태의 국부 괴사병반(SNS)이며, 다른 하나는 SNS보다 약간 큰 halo 형의 국부 괴사 병반(LNS)으로 뚜렷하게 구분되었다. 한편 황화 병징의 용담으로부터 증식된 접종원은 동부의 초생엽에 LNS만 형성하였다. 동부에 형성된 SNS 및 LNS형 병반을 각각 단일병반 분리하여 N. bentamiana에 접종하였다. 그 결과 SNS를 접종한 N. bentamiana에서는 접종엽에 무병징, 상위엽에는 전형적인 모자이크 증상이 발현되었다. 반면 LNS를 접종한 식물체에서는 접종엽에 퇴록 윤문이 형성되었으며, 상위엽에는 괴저를 동반한 모자이크 증상이 발현되었다. 이들 SNS 및 LNS 병반으로부터 분리한 바이러스를 dsRNA, RT-PCR 및 혈청학적 유연관계 분석을 통하여 SNS 병반은 CMV에 의해서, LNS는 BBWV2에 의해서 유도된다는 것을 확인하였다. 이 연구의 결과로부터 자연계에서 CMV와 BBWV2가 복합감염되어 병징의 구분이 어려운 경우, 동부에 접종하여 유도된 병반을 이용하여 두 바이러스의 감염을 쉽게 구분할 수 있는 방법으로 활용할 수 있을 것으로 생각되었다.

• The Plant Pathology Journal
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• 제24권1호
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• pp.93-96
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• 2008

In August 2006, a severe disease incidence showing mosaic and/or necrotic symptoms on two bell pepper varieties including red-colored 'Special' and yellow-colored 'Fiesta' was observed in a greenhouse located in Gwangyang, Jeonnam province, Korea. To identify causal viruses, total RNAs were extracted from 11 fruit samples with and without symptoms. Specific oligonucleotide primers for Cucumber mosaic virus (CMV), Pepper mottle virus (PepMoV), Tomato spotted wilt virus (TSWV) and Pepper mild mottle virus (PMMoV) were designed based on the sequences available on GenBank. Database comparisons of the deduced amino acid sequences of each sequence produced 100% and 98% matches with nucleocapsid protein gene of TSWV (Acc. No. ABE11605) and coat protein gene of CMV (Acc. No. DQ018289), respectively, suggesting that the symptoms on bell pepper fruits might be caused by the infection of CMV and TSWV. To our knowledge this is the first report of necrotic as well as mosaic virus disease on bell pepper fruits by the infection of CMV and TSWV in Jeonnam province, Korea.

• 한국연초학회지
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• 제7권1호
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• pp.7-13
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• 1985

Effect of the two PVY strains(PVY-VB and PVY-VN) on yield and chemical constituents of tobacco plants was determined in roar. NC2326 and Burley 21. The virus was inoculated 6 and 8 weeks after transplanting, respectively. The strains and time of inoculation were most critical factors for yield reduction. The greatest reduction was caused by the necrotic strain (PVY-VN) inoculated 6 weeks after transplanting, accounting for the loss of 40% in var. NC2326 and of 45% in var.. Burley21. When inoculated 8 weeks after transplanting with the necrotic strain, only 17% reduction was recorded in roar. Burley21, but no reduction occurred in roar. NC2326. Generally less reduction was caused by the PVY-VB strain, ranging 12-16% depending on the time of inoculation and/or variety. Compared to healthy tobacco, PVY infected tobacco contained higher concentrations of total nitrogen, protein nitrogen, nitrate nitrogen, and lower total sugar in cured leaf of roar. NC2326. Total alkaloid, P, Mg, Ca, and K levels were not altered. In var. Burley21, protein nitrogen and nitrate nitrogen increased, but other chemical components were not changed. Necrotic strain-infected tobacco with a severe symptom had higher nitrogen than did mild strain-infected tobacco.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.151.1-151
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• 2003

Chinese yam(D. opposita Thunb. cv. Jang-Ma) plants showing necrotic mosaic symptom were collected from their growing fields in Andong, Korea. Electron microscoptic examination of negatively stained preparations showed filamentous particles of 660nm in length. The virues purified partially were used to isolate Viral RNA as template for RT-PCR to amplify the CP gene with ChYNMV specific and oligo dT primers. Amino acids sequeces revealed that the viruses shared 99.3％ similarity with ChYNMV(AB044386) which was known as the member of macluravirus. So the viruses from Chinese yam(D. opposita Thunb. cv. Jang-Ma) plants were identified as ChYNMV. Comparing the amino aced sequences of ChYNMV strains with other macluraviruses such as CdMV, NLV and MacMV revealed that N-terminal was the most variable region and conserved regions were present within the genus Macluravirus.

• The Plant Pathology Journal
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• 제31권4호
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• pp.379-387
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• 2015

Melon necrotic spot virus (MNSV) was recently identified on watermelon (Citrullus vulgaris) in Korea, displaying as large necrotic spots and vein necrosis on the leaves and stems. The average occurrence of MNSV on watermelon was found to be 30-65% in Hapcheon and Andong City, respectively. Four isolates of the virus (MNSV-HW, MNSV-AW, MNSV-YW, and MNSV-SW) obtained from watermelon plants in different areas were non-pathogenic on ten general indicator plants, including Chenopodium quinoa, while they infected systemically six varieties of Cucurbitaceae. The virus particles purified by 10-40% sucrose density gradient centrifugation had a typical ultraviolet spectrum, with a minimum at 245 nm and a maximum at 260 nm. The morphology of the virus was spherical with a diameter of 28-30 nm. Virus particles were observed scattered throughout the cytoplasm of watermelon cells, but no crystals were detected. An ELISA was conducted using antiserum against MNSV-HW; the optimum concentrations of IgG and conjugated IgG for the assay were $1{\mu}l/ml$ and a 1:8,000-1:10,000 dilutions, respectively. Antiserum against MNSV-HW could capture specifically both MNSV-MN from melon and MNSV-HW from watermelon by IC/RT-PCR, and they were effectively detected with the same specific primer to produce product of 1,172 bp. The dsRNA of MNSV-HW had the same profile (4.5, 1.8, and 1.6 kb) as that of MNSV-MN from melon. The nucleotide sequence of the coat protein of MNSV-HW gave a different phylogenetic tree, having 17.2% difference in nucleotide sequence compared with MNSV isolates from melon.

• 한국연초학회지
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• 제5권1호
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• pp.43-47
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• 1983

Tobacco mosaic virus (TMV) was detected from Kimchi by biological and serological assay 5. Kimchi samples three month after cooked were collected, and were inoculated on N. tabacum var. Burley 21 and NC 95. Out of 33 samples, 6 showed typical symptoms induced by TMV, local necrotic lesions on Burley 21 and mosaic on NC 95. All saps from tobacco leaves showed the mosaic symptom reacted positively against TMV antiserum by agar gel double diffusion test. Based on the results, the Kimchi is considered as one of the important inoculum sources in Korea.

• 한국식물병리학회지
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• 제13권2호
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• pp.132-137
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• 1997

Phytotoxicity of the culture filtrate and culture conditions for the production of the phytotoxin by Exserohilum monoceras 92-044 were examined. The necrotic lesions were developed on the leaves of Echinochloa crus-galli within 48 hrs after inoculation of the culture filtrate, and the leaves were completely blighted within 5∼7 days. Maximum toxicity was found in the culture broth containing 20% V-8 juice. Phytotoxin accumulation and fungal growth reached their highest peak at around 11 days. Typical symptom appeared on the leaf of E. crus-galli within 48 hrs. Only a weak chlorosis appeared on rice, Arundinella hirta (THUNB) and henry crabgrass (Digitaria sanguinalis SCOP.), but no further symptom developed.

• The Plant Pathology Journal
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• 제31권4호
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• pp.421-427
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• 2015

Citrus scab disease is one of the destructive diseases that reduce the value of fruit for the fresh market. We analyzed the process of symptom development after infection with scab pathogen $Elsino{\ddot{e}}$ fawcettii in the susceptible satsuma mandarin leaves to observe the structural modification against pathogen. The cuticle and epidermal cells along with 3-5 layers of mesophyll tissue were degraded 1-2 days post inoculation. Surrounding peripheral cells of degraded tissues grew rapidly and then enveloped the necrotic area along with the growing conidia. Cross sections through the lesion revealed hyphal colonization in epidermis and mesophyll tissues. In response to the pathogen colonization, host cell walls were lignified, inner cells were rapidly compartmentalized and a semi-circular boundary was formed that separated the infected region from the non-infected region, and finally prevented the intercellular pathogen spread.