• Korean Journal of Veterinary Research
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• v.55 no.3
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• pp.185-189
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• 2015

Bovine parainfluenza virus type 5 (bPIV5) was isolated from cattle with downer cow syndrome in 2012, and included both respiratory and neurotropic pathogens from a variety of animals. In the current study, we conducted serosurveillance using sera obtained from seven Korean farms and optimized a reverse transcription-polymerase chain reaction (RT-PCR) assay to detect bPIV5. The overall seropositive rate for Korean cattle was 21.4% (163/760). A farm located near the city of Milyang in Gyeoungnam province had a markedly elevated seropositive rate for bPIV5 compared to that of the other six farms. The regional seropositive rates were 4.2% (8/192) for Haman, 19.5% (18/55) for Hwasung, 73.9% (65/88) for Milyang, 26.0% (50/192) for Namwon, 1.0% (1/96) for Uljin, 13.5% (13/96) for Yeongju, and 32.7% (8/41) for Yongin. The sensitivity and specificity of three RT-PCR primer sets used to amplify the conserved fusion gene of bPIV5 were also evaluated. An RT-PCR assay using the bPIVFR3 primer set was 10-fold more sensitive than the assays using the two other primer sets and did not result in non-specific amplification. These results demonstrated that the bPIFR3 primer set can be used to detect bPIV5.

• Molecules and Cells
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• v.19 no.2
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• pp.228-231
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• 2005

Recent characterization of several genes involved in plant defense responses suggested that ubiquitin-mediated protein degradation has a role in these responses. We isolated two cDNAs (NtUBA1 and NtUBA2) encoding ubiquitin-activating enzyme (E1) from Nicotiana tabacum cv. BY-2. The open reading frames of both encoded 1080 amino acids, corresponding to molecular masses of 120 kDa. The E1s and corresponding transcripts were upregulated by infection with tobacco mosaic virus (TMV) and tomato mosaic virus (ToMV), and to a lesser extent by cucumber mosaic virus (CMV). Furthermore, they were also upregulated by wounding stress, and the plant hormones salicylic acid, jasmonic acid and the ethylene precursor, aminocyclopropane-1-carboxylic acid (ACC). Our findings support the idea that the ubiquitin-proteasome system plays a role in plant disease defenses.

• The Plant Pathology Journal
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• v.17 no.3
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• pp.169-173
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• 2001

Virus disease occurred up to 62% in average in the greenhouse production of table tomato Seokwang in Suwon, Korea. From symptomatic transition of the labeled tomatoes, two different symptoms, mosaic and bud necrosis, were developed independently. Cucumber mosaic virus necrosis strain (CMV-N) was isolated from table tomato showing bud necrosis symptoms. The isolate caused the bud necrosis on four tomato cultivars and locally infected Chenopodium spp. and Vicia faba by mechanical inculation. The 5th RNA segment, satellite RNA, was identified from CMV-N-infected plants by dsRNA analysis. Crystals of virus particles were observed in cytosols and vacuoles. The virus particles of CMV-N presented abundantly in xylem vessel.

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.280-286
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• 2007

We evaluated a commercial biopreparation of plant growth-promoting rhizobacteria (PGPR) strains Bacillus subtilis GB03 and B. amyloliquefaciens IN937a formulated with the carrier chitosan (Bio Yield) for its capacity to elicit growth promotion and induced systemic resistance against infection by Cucumber Mosaic Virus (CMV) and Pseudomonas syringae pv. tomato DC3000 in Arabidopsis thaliana. The biopreparation promoted plant growth of Arabidopsis hormonal mutants, which included auxin, gibberellic acid, ethylene, jasmonate, salicylic acid, and brassinosteroid insensitive lines as well as each wild-type. The biopreparation protected plants against CMV based on disease severity in wild-type plants. However, virus titre was not lower in control plants and those treated with biopreparation, suggesting that the biopreparation induced tolerance rather than resistance against CMV. Interestingly, the biopreparation induced resistance against CMV in NahG plants, as evidenced by both reduced disease severity and virus titer. The biopreparation also elicited induced resistance against P. syringae pv. tomato in the wild-type but not in NahG transgenic plants, which degrade endogenous salicylic acid, indicating the involvement of salicylic acid signaling. Our results indicate that some PGPR strains can elicit plant growth promotion by mechanisms that are different from known hormonal signaling pathways. In addition, the mechanism for elicitation of induced resistance by PGPR may be pathogen-dependent. Collectively, the two-Bacilli strain mixture can be utilized as a biological inoculant for both protection of plant against bacterial and viral pathogens and enhancement of plant growth.

• Research in Plant Disease
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• v.13 no.1
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• pp.1-5
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• 2007

Major diseases of tobacco and farmer's control practices were surveyed in the Kyeongbuk province area from 2005 to 2006. Mosaic caused by potato virus Y and bacterial wilt caused by Ralstonia solanacearum were most severe during the harvest season. Compared with the disease occurrence of ten years ago, the damage by tobacco mosaic virus reduced but bacterial wilt increased. These changes in the disease occurrences may probably be due to releasing the resistant tobacco cultivar to the mosaic virus but susceptible to the bacterial wilt pathogen. More than thirty percentage of the farmers have misused fungicides and also have applied the continuous mono-cropping system for more than ten years, and have chosen the incorrect crops for the rotation.

• The Plant Pathology Journal
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• v.18 no.6
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• pp.313-316
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• 2002

Systemic virus symptoms caused by a Potexvirus were observed on leaves of infected hosta (Hasta spp.) plants cultivated in Seoul, Korea. Symptoms on diseased hosta plants include mosaic, mottle, irregular blotchy patches, and chlorotic spots on or distortion of the leaves. No other viruses, such as Cucumber mosaic virus, Lily symptomless virus, or Potyvirus, were detected from the same plants by electron microscopy and by Western blot and RT-PCR analyses, indicating that they were singly infected by the potexvirus. The symptoms differed among cultivars and species of hosta, and affected the quality of plants for commercialization, as well as, plant growth and flowering of susceptible cultivars. Most of the cultivars and species investigated were susceptible to the virus, while some were not infected by the virus at all. Purified virus particles were of filamentous type with unaggregated forms 540 nm in length, which is a typical potexviral morphology. The virus consisted of a single-stranded RNA molecule of 6 kb long for genome and single component of coat protein (CP) about 27 kDa. The CP strongly reacted with the antiserum against Hosta vims X (HVX), suggesting that the virus is an isolate of HVX. This is the first report of the occurrence and identification of HVX from hosta plants in Korea.

• Korean Journal of Veterinary Service
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• v.42 no.1
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• pp.25-30
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• 2019

The objective of this study was to assess the possibility of detecting Foot-and-Mouth Disease Virus (FMDV) from the herd-based oral fluids specimens collected by the cotton ropes from pig farms that were found as FMDV nonstructural protein (NSP) antibodies positive. The cotton ropes were applied to detect FMDV in the selected pig farms which NSP antibodies were continuously detected in 2016, including the one pig farm which FMDV antigen were detected at the specimens from the pigsty environment. As the result, FMDV antigen were not detected in the oral fluid specimens collected by the cotton ropes. Theoretically, to detect FMDV antigen from the pigs with NSP antibodies has very low possibility because FMDV antigen disappeared at the time when NSP antibodies were produced by FMDV. Therefore, in order to detect FMDV antigen from the oral fluids using the cotton rope, it would be more effective to be applied to target the FMDV infected pigs rather than the NSP antibodies positive pigs. The collected oral fluids using cotton rope could be useful test specimens to monitor high-density pig populations for FMDV infection. Then, oral fluids sampling using cotton rope will be used for the efficient FMDV surveillance to detect FMDV antigen.

• Korean Journal of Veterinary Research
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• v.62 no.1
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• pp.10.1-10.9
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• 2022

Feline panleukopenia virus (FPV) causes fatal leukopenia and severe hemorrhagic diarrhea in cats. Although FPV isolates have been reported worldwide from several animals, the biological and genetic features of South Korean FPVs remain unclear. We characterized molecularly South Korean FPV isolates. Crandell-Rees feline kidney (CRFK) cells were used to isolate FPV from 60 organ homogenates. The isolates were confirmed to be FPVs via analyses of cytopathic effects, immunofluorescence studies, electron microscopy, and polymerase chain reaction. Viral genetic analyses used the full VP2 sequences. Eight isolates propagated in CRFK cells were confirmed to be FPVs. All isolates yielded viral titers ranging from 10^4.5 to 10^6.0 TCID₅₀/mL 5 days after inoculation into CRFK cells and exhibited hemagglutination titers ranging from 2⁷ to 2¹² (using pig erythrocytes). The Korean FPV isolates grew well in cat cells such as CRFK and Fcwf-4 cells. The FPV isolates were most similar to the KS42 strain isolated from a Korean cat in 2008. The FPV isolates will serve as useful antigens in future sero-epidemiological studies and will aid in the development of diagnostic tools.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.54-54
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• 2019

Apple (Malus domestica) is one of the most economically important fruits in Korea. But virus infection has decreased sustainable production of apple and caused the serious problems such as yield loss and poor fruit quality. Virus or viroid infection including Apple chlorotic leaf spot virus (ACLSV), Apple stem pitting virus (ASPV), Apple stem grooving virus (ASGV), Apple mosaic virus (ApMV) and Apple scar skin viroid (ASSVd) has been also reported in Korea. In many cases, apple is infected with virus and viroid with no specific symptoms, the damage caused by the virus are unaware significantly. In our research, we tried to eliminate viruses in the rootstock for the disease-free seedlings of the apple dwarfing rootstock M.9 and M.26. The method of virus elimination was meristem culture, heat($37^{\circ}C$, 6weeks) treatment and chemistry($Ribavirin^{(R)}$) treatment. The analytical methods commonly used for the detection of virus is Enzyme-linked Immuno-Sorbent Assay(ELlSA) and Reverse Transcription-polymerase Chain Reaction(RT-PCR). RT-PCR method was more 30% sensitive than ELISA method. Efficiency of method eliminate virus appeared meristem method > heat treatment > chemistry treatment. The higher acquisition rate of disease-free seedlings is 30~40% on meristem treatment. In meristem treatment, the apple dwarfing rootstock M.9 gained infection ratio of ACLSV, ASPV and ASGV were 45%, 60% and 50% respectively. In the apple dwarfing rootstock M.26, infection ratio of ACLSV, ASPV and ASGV were 40%, 55%, 55%, respectively. Based on our results, it was found that most effective method of disease-free seedlings apple dwarfing rootstocks was by meristem treatment than heat method and chemistry treatment.

• The Plant Pathology Journal
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• v.30 no.4
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• pp.407-415
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• 2014

Viral diseases have been a major limiting factor threating sustainable potato (Solanum tuberosum L.) production in Pakistan. Surveys were conducted to serologically quantify the incidence of RNA viruses infecting potato; Potato virus X (PVX), Potato virus Y (PVY), Potato virus S (PVS), Potato virus A (PVA), Potato virus M (PVM) and Potato leaf roll virus (PLRV) in two major potato cultivars (Desiree and Cardinal). The results suggest the prevalence of multiple viruses in all surveyed areas with PVY, PVS and PVX dominantly widespread with infection levels of up to 50% in some regions. Co-infections were detected with the highest incidence (15.5%) for PVX and PVS. Additionally the data showed a positive correlation between co-infecting viruses with significant increase in absorbance value (virus titre) for at least one of the virus in an infected plant and suggested a synergistic interaction. To test this hypothesis, glasshouse grown potato plants were challenged with multiple viruses and analyzed for systemic infections and symptomology studies. The results obtained conclude that multiple viral infections dramatically increase disease epidemics as compared to single infection and an effective resistance strategy in targeting multiple RNA viruses is required to save potato crop.