• Research in Plant Disease
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• v.13 no.1
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• pp.30-33
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• 2007

One hundred and eighty-six leaves of soybean cv. Seokryangputkong that showed mild mosaic symptoms were collected randomly and ELISA tests were conducted with those leaf samples to screen the presence of Cowpea mosaic virus (CPMV). Ninety-three out of 186 samples reacted positively to CPMV, but those samples did negatively to Soybean mosaic virus (SMV). At least, 55 leaf samples revealed higher values than that of positive control. The results strongly confirmed that CPMV occurred severely in soybean cv. Seokryangputkong. However, a question is raised on the primary reservoir and vector for transmission of this virus. Since the farmer changes seeds every year, seed transmission is excluded. The virus was also purified, the analysis of coat protein conformed the virus of cowpea mosaic virus and UV absorption pattern confirmed that the causal virus of mosaic disease in soybean putkong was cowpea mosaic virus.

• Korean Journal of Veterinary Service
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• v.23 no.3
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• pp.301-306
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• 2000

In an outbreak of acute porcine diarrhea in newborn piglets, an etiological study was carried out using piglets submitted in Cheju Province Institute for Livestock Promotion(Cheju Veterinary Service for the disease diagnosis). Sixteen piglets(2-7 days old) were collected from 4 farms during outbreaks of diarrhea disease(from January to April 2000). Specimens were taken after necropsy and examined by immunohistochemistry using of monoclonal antibodies for porcine epidemic diarrhea(PED) virus, transmissible gastroenteritis(TGE) virus, and porcine rotavirus. Immunohistochemistry showed that PED virus antigens, but both TGE virus and rota virus antigens not, were localized in the some epithelial cells of the intestines of 14 animals among 16 piglets examined. PEB virus antigens were mainly detected in the cytoplasm of enterocytes. Infected cells, which were most abundant in the villous epithelial cells of the jejunum and ileum, were uncommon in the crypt, epithelial cells, the lamina propria and Peyer's patches of piglets examined. The results suggest that PED virus is one of the most prevailing agents in an outbreak of fatal diarrhea in newborn piglets on Cheju island and PED virus was need to further study to prevent this disease.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.4
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• pp.465-469
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• 1996

Pathological and virological investigations were conducted on suspected outbreaks of infectious bursal disease (IBD) in a broiler farm and five pullet-raising poultry farms of Mymensingh and Tangail districts of Bangladesh. About 80 to 100 percent chicks were affected at the age of 26 to 45 days and mortality varied from 20 to 30 percent in broilers and 40 to 80 percent in layer chicks. Signs, symptoms, gross and microscopic lesions were typical of acute IBD. Several isolates of virus could be obtained by embryo inoculation and the virus was diagnosed as infectious bursal disease virus (IBDV) by agar gel immunodiffusion test (AGID). The virus isolate belonged to the very virulent pathotype of IBDV causing 100 percent mortality in three weeks old chicks on experimental infection.

• Korean Journal of Organic Agriculture
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• v.23 no.1
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• pp.123-131
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• 2015

In this study, viral disease samples were obtained between 2006 and 2010 from pepper fields in 11 major pepper-growing districts in Gangwon-do, and in 83 areas from other provinces, with the exception of Gyeongsangnam-do and Jeju island in Korea. In order to assess the type of infection, field surveys were conducted with regard to viral disease severity and virus type, based on typical symptoms on leaves. The means of single and mixed-virus infections were 46.6% and 48.0%, respectively, during those periods, suggesting that viruses are the agents that most severely decrease pepper production in field cultivation in Korea. In terms of single infection, Cucumber mosaic virus (CMV) was the most prevalent virus based on its disease severity ratings (34.8%). Next, Pepper mild mottle virus (PMMoV) and Pepper mottle virus (PepMoV) were shown to cause severe viral diseases in pepper, with disease severities of around 5-10%. On the other hand, Tomato spotted wilt virus (TSWV) occurs in a limited area in Chungcheongnam-do and Jeollanam-do. Thus, the viral disease caused by CMV, PMMoV, and PepMoV in pepper can be severe, and these virus types should remain considered critical reasons for decreased pepper production in field cultivation in Korea. In addition to single infection, mixed infections are frequently observed in collected pepper samples from all areas. The ratios of mixed infection were therefore studied to evaluate the disease severity of mixed infections and to define individual virus types. These data showed that different types of viruses were present, and CMV was the most abundant virus for mixed infection, as in the case of single infection. Among mixed infections, the highest disease severity was seen with CMV+Broad beam wilt virus 2 (BBWV2), followed by other types of mixed infection such as CMV+PepMoV and CMV+PMMoV. However, further work is needed to reduce the severe damage caused by viruses and to assess mixed infection types involving three or more viruses.

• Korean Journal of Poultry Science
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• v.39 no.2
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• pp.113-120
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• 2012

Newcastle disease virus (NDV) Kr005/V strain was generated through 55 serial passages of NDV Kr005 strain in Vero cells. The Kr005/V virus yielded high infective titers of $10^{7.8}$ $TCID_{50}/mL$ in Vero cells and the infected cells showed cytopathic effects such as marked cell rounding, though less frequent syncytia. The Kr005/V virus was heat-stable and classified into the lentogenic type with a Mean Death Time (MDT) of 120h or greater while the Kr005 strain was heat-labile and velogenic (MDT of 49.6 h). Only the single amino acid substitution (T to S) was observed at position 433 of the HN protein of the Kr005/V strain, whereas no amino acid change was found in the F protein. The Kr005/V input virus correlated well (correlation coefficient $r^2$=0.97) with the Kr005 virus when ten field sera were tested by virus neutralization test. The biological properties and usefulness of Vero cell-adapted Kr005/V virus were discussed.

• Korean journal of applied entomology
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• v.16 no.2 s.31
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• pp.87-92
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• 1977

A barley virus disease has been severe in central Korea since 1963. To investigate the causal virus, examination of host ranges, transmission by insect vectors and · electron microscopy were conducted. In electron microscopy, particles identical with northern cereal mosaic virus were observed. The size of baciliform particles ranged from 300nm to 370nm in length and 57-60nm in diameter. The virus was transmitted by the small brown planthopper Laodelphax striatellus (Fallen). The latent period in the vector was seven to nineteen days, with 10 days the most prevalent. Barley, corn, wheat, rye, and oats were susceptible to the virus when inoculated by the insect vectors. It was concluded that the disease agent of the barley disease in Korea is northern cereal mosaic virus. This is the first known report of this disease in Korea.

• Journal of Animal Science and Technology
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• v.57 no.4
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• pp.10.1-10.7
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• 2015

Control and prevention of foot and mouth disease (FMD) by vaccination remains unsatisfactory in endemic countries. Indeed, consistent and new FMD epidemics in previously disease-free countries have precipitated the need for a worldwide control strategy. Outbreaks in vaccinated animals require that a new and safe vaccine be developed against foot and mouth virus (FMDV). FMDV can be eradicated worldwide based on previous scientific information about its spread using existing and modern control strategies.

• The Plant Pathology Journal
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• v.23 no.3
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• pp.215-218
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• 2007

The occurrence and relative incidence of viruses including Cucumber mosaic virus (CMV), Zucchini yellow mosaic virus (ZYMV), Papaya rings pot virus (PRSV), and Watermelon mosaic virus (WMV), Cucumber green mottle mosaic virus (CGMMV), Kyuri green mottle mosaic virus (KGMMV), and Melon necrotic spot virus (MNSV) were surveyed from main melon (Cucumis melo L.) production areas in Jeonnam province during 2000-2002. Virus disease incidences of melon cultivating fields were 0% and 11% in spring and fall 2000; 40%, 2.1%, and 8.8% in spring, summer, and fall 2001; and 6.3 % in spring 2002 in main cultivated areas in Jeonnam province, respectively. Field disease incidences of melon virus infections were 0% and 18.8% in spring and fall 2000; 50%, 38.5%, and 82.6% in spring, summer, and fall 2001; and 47.4% in spring 2002, respectively. Total of 101 melon samples showing typical disease symptoms were collected from 2000 to 2002 and tested for virus infection by RT-PCR. Potyvirus-specific DNA fragments for WMV, ZYMV, and PRSV were amplified from 46, 5, and 4 samples, respectively. MNSV specific DNA fragment was amplified from 18 samples. CMV-specific DNA fragment was detected from only 3 samples.

• Korean Journal of Veterinary Research
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• v.62 no.3
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• pp.24.1-24.7
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• 2022

Incidences of major feline viral diseases provide basic information for preventing viral disease in cats. Despite the growing interest in feline viral diseases, sero-surveillances have been lacking. In this study, we analyzed the diagnoses of feline viral diseases and conducted a sero surveillance of feline panleukopenia virus (FPV), feline calicivirus (FCV), feline herpesvirus-1 (FHV-1), and feline infectious peritonitis virus (FIPV) in Korean cats. Of the 204 confirmed cases since 2015, the numbers of diagnoses for FPV, FIPV, FCV, feline influenza virus, and FHV-1 were 156, 32, 12, 3, and 1 case, respectively. In total, 200 sera, collected between 2019 and 2021, were screened for the presence of antibodies against FPV, 2 FCVs, FHV-1, and FIPV using a hemagglutination inhibition test and a virus-neutralizing assay (VNA). The overall seropositive rates in cats tested for FPV, the 2 FCVs, FHV-1, and FIPV were 92.5%. 42.0%, 37.0%, 52.0%, and 14.0%, respectively. A low correlation (r = 0.466) was detected between the VNA titers of 2 FCV strains. The highest incidence and seropositive rate of FPV reveal that FPV is circulating in Korean cats. The low r-value between 2 FCVs suggests that a new feline vaccine containing the 2 kinds of FCVs is required.

• Research in Plant Disease
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• v.15 no.1
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• pp.8-12
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• 2009

Virus disease surveys of strawberries cultivated and preserved as germplasm resources in Korea was conducted during 2007-2008. Virus detection was conducted by RT-PCR using total RNAs extracted from strawberry samples. We detected the infection with Strawberry mild yellow edge virus (SMYEV), Strawberry mottle virus (SMoV), Strawberry vein banding virus (SVBV) and Strawberry pallidosis associated virus (SPaV) while no infection with Strawberry crinkle virus (SCV), Strawberry necrotic shock virus (SNSV), Strawberry latent ring spot virus (SLRSV) and Arabis mosaic virus (ArMV) was observed. The infection rate of virus disease on 4 cultivars including Seolhyang, Maehyang, Gumhyang, and Dahong, bred in Korea, was 0.1, 1.9, 0, and 0%, respectively. Surprisingly, however, cultivar Red Peal introduced from Japan in 1997 revealed 48.3% virus infection rate. SMYEV, SMoV and SPaV were also identified in strawberries growing in the farm fields of Korea. In the field, however, SMYEV was the most predominant virus (97.4%) among those 3 identified viruses. SVBV was detected only in strawberry kept as a germplasm.