• Korean Journal of Veterinary Research
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• v.57 no.2
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• pp.143-146
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• 2017

Porcine ear necrosis syndrome is characterized by erosive and ulcerative lesions at the margin or tip of the pinna. Three growing pigs of different ages exhibited retarded growth accompanied by reddening and necrosis of ear prior to death. Gross examination showed reddening, swelling, black discoloration, scaling, and variable-sized yellowish materials and edema in ear cross section. Microscopically, thrombosis, abscess, ulceration, epidermal hyperplasia, and dermal pyogranulomatous inflammation with an intralesional bacterial colony were observed. Staphylococcus hyicus was isolated in all pigs' ears and porcine reproductive and respiratory syndrome virus was detected by PCR and immunohistochemistry.

• Research in Plant Disease
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• v.19 no.4
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• pp.331-337
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• 2013

A disease, supposedly caused by a virus, was observed from Insam (Panax ginseng) fields of Punggi in year 2006. It has long believed to be a physiological disorder. However, the incidence of the disease has increased every year. When several samples were observed under electron microscope, filamentous virus-like particles were observed. The nucleotide sequences of the virus were analyzed by RT-PCR with specific primer sets derived from the results of DNA chip. The results indicated that the disease was caused by Watermelon mosaic virus (WMV). It revealed that the result of the biological assay by the virus was different from that of WMV previously found in other crops. Therefore, this is the first report that WMV causes the disease in P. ginseng and the virus is named to be WMV-Insam.

• Research in Plant Disease
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• v.14 no.2
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• pp.138-141
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• 2008

Cucumber is high valued cash crop, for it is grown during the winter season in plastic house. Recently, virus disease spread widely in cucumber growing area and cause severe income loss. Therefore, occurrence of virus disease on cucumber were surveyed from 2004 to 2006 in Sangju and Gunwi area, Gyeongbuk province. The rate of plastic house which has infected plants was $55.0{\sim}88.6%$. Infection rate was the highest at Sangju in 2006 than others and ranged from 15 to 90.0% per plastic house. The 217 samples showing virus symptom were analyzed by RT-PCR using appropriate detection primer. Zucchini yellow mosaic virus(ZYMV) has the highest infection rate(detected over 85%) and followed by Cucumber green mottle mosaic virus(CGMMV). But Watermelon mosaic virus-2(WMV-2) was not detected in our survey. Therefore, we conclude that ZYMV is major pathogene of virus disease on cucumber. ZYMV induced chlorosis and severe mosaic on the leaves and distortion on the surface of fruits.

• Research in Plant Disease
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• v.24 no.4
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• pp.348-352
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• 2018

A multiplex reverse transcription-polymerase chain reaction (mRT-PCR) assay was developed for the detection of Clover yellow vein virus (ClYVV), Peanut mottle virus (PeMoV), and Tomato spotted wilt virus (TSWV), which were recently reported to infect soybean and azuki bean in Korea. Species-specific primer sets were designed for the detection of each virus, and their specificity and sensitivity were tested using mixed primer sets. From among the designed primer sets, two combinations were selected and further evaluated to estimate the detection limits of uniplex, duplex, and multiplex RT-PCR. The multiplex RT-PCR assay could be a useful tool for the field survey of plant viruses and the rapid detection of ClYVV, PeMoV, and TSWV in leguminous plants.

• Korean Journal of Veterinary Service
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• v.35 no.2
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• pp.129-131
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• 2012

Blood samples were collected from 672 goats in 60 farms from five provinces of Korea between November 2009 and August 2011. The prevalence of antibodies to pestiviruses was investigated. The examination for antibodies was performed using an enzyme-linked immunosorbent assay (ELISA) detecting antibodies to the bovine viral diarrhea virus (BVDV) and border disease virus (BDV). All blood samples were screened using reverse transcription-polymerase chain reaction (RT-PCR) with primer pairs specific to common pestivirus genome regions. The observed individual seroprevalence was 1.49% and herd seroprevalence was 11.67%. Also, the specific genomes to pestiviruses were detected in 3 out of the 915 clinical samples (0.45%). Based on the nucleotide sequence data, detected pestiviruses were belonged to two BVDV type-1 and one BVDV type-2. The pestivirus infection has been occurred among Korean black goats. However, our results indicate that the prevalence of pestiviruses in black goats was not significantly higher on farms with cattle.

• Research in Plant Disease
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• v.29 no.1
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• pp.94-99
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• 2023

Blueberry red ringspot virus (BRRSV) and blueberry scorch virus (BlScV) are included in the quarantine virus list managed by the Korean Animal and Plant Quarantine Agency. A multiplex polymerase chain reaction (PCR) assay with an internal control was developed for the simultaneous detection of both viruses. The specific primers used here were designed based on the highly conserved regions of the genomic sequences of each virus, obtained from the National Center for Biotechnology Information nucleotide databases. The primers were designed to amplify a partial sequence within coat protein (CP) for detecting BRRSV and a partial sequence within the CP-16 kDa for detecting BlScV. 18S ribosomal RNA (rRNA) was used as internal control, and the primer set used in a previous study was modified in this study for detecting 18S rRNA. Each conventional PCR using the BRRSV, BlScV, and 18S rRNA primers exhibited a sensitivity of approximately 1 fg plasmid DNA. The multiplex PCR assay using the BRRSV, BlScV, and 18S rRNA primers was effective in simultaneously detecting the two viruses and 18S rRNA with a sensitivity of 1 fg plasmid DNA, similar to that of conventional PCR assays. The multiplex PCR assay developed in this study was performed using 14 blueberry cultivars grown in South Korea. BRRSV and BlScV were not detected, but 18S rRNA was all detected in all the plants tested. Therefore, our optimized multiplex PCR assay could simultaneously detect the two viruses and 18S rRNA in field samples collected from South Korea in a time-efficient manner. This approach could be valuable in crop protection and plant quarantine management.

• Korean Journal of Agricultural Science
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• v.40 no.2
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• pp.93-99
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• 2013

The disease and insect were surveyed locally in greenhouse, fruit packing house and store house of 51 farms in 13 towns having purpose of paprika exportation. By analysis, various disease and insect were not only founded locally but more ones detected in farms having old facilities and no natural enemy. We found 15 pathogens such as Fusarium spp., Alternaria solani, Leveilluila taurica, PepMV (Pepino mosaic virus) and TMV (Tobacco mosaic virus) in greenhouse, Fusarium spp. in fruit packing house and Penicillium spp. in store house. We found 15 insects in greenhouse such as Bemisia tabaci, rialeurodes vaporariorum and Myzus persicae in greenhouse, Hylobitelus haroldi in fruit packing house. However, the problem quarantine disease and insect for importation and exportation were not detected in inspection time.

• The Plant Pathology Journal
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• v.24 no.1
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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.

• The Plant Pathology Journal
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• v.35 no.1
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• pp.32-40
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• 2019

Symptoms of fig mosaic disease have been noticed on leaves of fig (Ficus carica) for several decades, in Montenegro. In 2014, leaf samples were collected from trees of six fig cultivars in a plantation located in the main fig-producing area of Montenegro, to study the disease. After RNA isolation, samples were tested by RT-PCR for detection of nine fig viruses and three viroids. Four viruses were detected: fig leaf mottle-associated virus 1 (FLMaV-1), fig mosaic virus (FMV), fig mild mottle-associated-virus (FMMaV) and fig badnavirus 1 (FBV-1). Most of the viruses were present in mixed infections. The amplicons of the viruses were directly sequenced from both directions. A BLAST search of these sequences revealed sequence identities with their closest counterparts at GenBank of 92, 97, 92 and 100%, for FLMaV-1, FMV, FMMaV and FBV-1, respectively. Different responses in symptom expression due to the various virus combinations detected have been demonstrated. Variety $Su{\check{s}}ilica$ had the least symptom expression, with only one virus (FBV-1) found. Considering that the production of figs in Montenegro is increasing and has a substantial relevance in this geographic location, the results indicate that more attention should be given to improving the phytosanitary condition of fig trees in the country.

• Research in Plant Disease
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• v.24 no.1
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• pp.9-25
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• 2018

Plant viruses cause significant yield losses and continuously threaten crop production, representing a serious threat to global food security. Studies on plant-virus interactions have contributed to increase our knowledge on plant immunity mechanism, providing new strategies for crop improvement. The prophylactic managements consist mainly following international legislations, eradication of infected plants, and application of pesticide to decrease the population of vectors. Hence, putting together the pieces of knowledge related to molecular plant immunity to viruses is critical for the control of virus disease in fields. Over the last several decades, the outstanding outcomes of extensive research have been achieved on comprehension of plant immunity to viruses. Although most dominant R genes have been used as natural resistance genes, recessive resistance genes have been deployed in several crops as another efficient strategy to control viruses. In addition, RNA interference also regulates plant immunity and contribute a very efficient antiviral system at the nucleic acid level. This review aims at describing virus disease on crops and summarizes current resistance mechanisms. Furthermore, we will discuss the current biotechnological approaches to control viral diseases and the future questions that are to be addressed to secure crop production against viruses.