• Korean Journal of Veterinary Research
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• v.55 no.2
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• pp.149-152
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• 2015

An abnormally enlarged right ovary and a mass in fat surrounding the right kidney were discovered in a dairy cow during routine postmortem examination at slaughter. The ovary was dark reddish and multinodular in shape. Numerous cystic structures were identified in the mass. Histopathologically, the ovary was completely replaced with large, uniform, polyhedral neoplastic cells containing vesicular nuclei and prominent nucleoli. The mitotic index was high. In the lymphatic vessels, tumor emboli were observed. Another mass in the fat surranding the right kidney had the same histological features as the ovarian mass. This animal was diagnosed with malignant dysgerminoma and metastasis to other peritoneal organs.

• Research in Plant Disease
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• v.24 no.2
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• pp.138-144
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• 2018

In December 2016, stem rot symptoms were observed on Persian buttercup (Ranunculus asiaticus) plants in Chilgok, Gyeongbuk, Korea. In the early stage of the disease, several black spots appeared on the stem of infected plants. As the disease progressed, the infected stem cleaved and wilted. The causal agent was isolated from a lesion and incubated on Reasoner's 2A (R2A) agar at $25^{\circ}C$. Total genomic DNA was extracted for phylogenetic analysis. Based on the 16S rRNA gene analysis, the isolated strain was found to belong to the genus Pseudomonas. To identify the isolated bacterial strain at the species level, the nucleotide sequences of the gyrase B (gyrB) and RNA polymerase D (rpoD) genes were obtained and compared with the sequences in the GenBank database. As the result, the causal agent of the stem rot disease was identified as Pseudomonas marginalis. To determine the pathogenicity of the isolated bacterial strain, it was inoculated into the stem of healthy R. asiaticus plant, the inoculated plant showed a lesion with the same characteristics as the naturally infected plant. Based on these results, this is the first report of bacterial stem rot on R. asiaticus caused by P. marginalis in Korea.

• Korean Journal of Veterinary Research
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• v.57 no.1
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• pp.37-42
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• 2017

Getah virus (GETV) infection causes sporadic outbreaks of mild febrile illness in horses and reproductive failure in pigs. In this study, we established a reverse transcription polymerase chain reaction (RT-PCR) method to detect GETV from suspected virus-infected samples. The reaction conditions were optimized and validated by using RNA extracted from GETV propagated in cell culture. A GETV-specific GED4 primer set was designed and used to amplify a 177 bp DNA fragment from a highly conserved region of the E1 glycoprotein gene in the GETV genome. RT-PCR performed with this primer set revealed high sensitivity and specificity. In the sensitivity test, the GED4 primer set detected GETV RNA at the level of $10^{2.0}\;TCID_{50}/mL$. In the specificity test, the GED4 primer set amplified only a single band of PCR product on the GETV RNA template, without non-specific amplification, and exhibited no cross-reactivity with other viral RNAs. These results suggest that this newly established RT-PCR method is useful for accurate identification of GETV infection in animals.

• Research in Plant Disease
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• v.28 no.4
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• pp.248-251
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• 2022

In October 2022, common Asian cowpea (Vigna nakashimae) powdery mildew disease was investigated at Yesan-gun, Chungcheongnam-do, Korea (36°40'12.7"N,126°51'36.4"E). The disease mainly occurred on the front of the leaves, and weak powdery mildew disease occurred on the back side of leaf. The chasmothecia was identified on the back side of the leaf. Analysis of the internal transcribed spacer rDNA sequence and 28S large subunit sequence, along with the morphological characteristics of the anamorph and teleomorph of the causal fungus identified as Podosphaera xanthii. This is the first time in Korea to report common Asian cowpea (Vigna nakashimae) powdery mildew disease caused by Podospaera xanthii.

• Korean Journal Plant Pathology
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• v.14 no.5
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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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• v.17 no.2
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• pp.83-87
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• 2001

Disease resistance in plants is often controlled by gene-for-gene mechanism in which avirulence (avr) gene products encoding by pathogens are specifically recognized, either directly or indirectly by plant disease resistance (R) gene products. Recent studies arising from molecular cloning of a number of R genes from various plant species that confer resistance to different pathogens and corresponding avr genes from various pathogens resulted in the accumulation of a wealth of knowledge on mode of action of gene-for-gene interaction. Specially, members of the NBS-LRR class of R genes encoding proteins containing a nucleotide binding site (NBS) and carboxyl-terminal leucine-rich repeats (LRRs) confer resistance to very different types of phytopathogens, such as bacteria, fungi, oomycetes, viruses, nematodes and aphids. This article reviewed the molecular events that occur up-stream of defense response pathway, specially, bacterial avr gene protein recognition mediated by NBS-LRR type R gene product in plant based on current research results of well studied model plants.

• Plant Disease and Agriculture
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• v.2 no.2
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• pp.42-44
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• 1996

• The Plant Pathology Journal
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• v.19 no.4
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• pp.205-209
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• 2003

Dispersal of citrus bacterial canker caused by Xanthomonas axonopodis pv. citri on Unshiu orange was investigated in naturally infested nursery plot at Seogwipo in Jeju island, Korea. Based on phage detection, over 2% of the bacterial pathogen over-wintered in canker lesions and started to multiply in late May. However, symptoms were first observed 1 month after the phage detection. The disease dispersed non-directionally to nearby plants possibly because of indirect dissemination of the bacterium by rain splashes. The disease increased from late June to late August and decreased thereafter. Population of phage increased constantly, however, disease occurrence somewhat fluctuated due to environmental factors. Disease incidence and severity were correlated with rainfall with wind that occurred 14-32 days earlier from late May to late August.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.123-126
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• 2011

To investigate the forecasting of plant disease and insect for an agricultural complex and farm in environment-friendly cultivation of Rice, environment-friendly agricultural five complexs and five farms were selected in Youngam and Naju area, Jonnam, Korea. Preventation objects of plant disease and insect were leaf blast, neck blast, sheath blight, bacterial leaf blight, and hopper. Factors of sheath blight occurrence in environment-friendly agricultural complex were a fast transplanting time and a narrow planting density. Bacterial leaf blight in rice occurred severely in the area under water. Rice growth in environment-friendly agricultural complex was decreased heavy drying by hopper appearance.

• The Plant Pathology Journal
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• v.33 no.3
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• pp.238-248
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• 2017

Pokkah Boeng is a serious disease of sugarcane, which can lead to devastating yield losses in crop-producing regions, including southern China. However, there is still uncertainty about the causal agent of the disease. Our aim was to isolate and characterize the pathogen through morphological, physiological, and molecular analyses. We isolated sugarcane-colonizing fungi in Fujian, China. Isolated fungi were first assessed for their cell wall degrading enzyme capabilities, and five isolates were identified for further analysis. Internal transcribed spacer sequencing revealed that these five strains are Fusarium, Alternaria, Phoma, Phomopsis, and Epicoccum. The Fusarium isolate was further identified as F. verticillioides after Calmodulin and EF-$1{\alpha}$ gene sequencing and microscopic morphology study. Pathogenicity assay confirmed that F. verticillioides was directly responsible for disease on sugarcane. Co-inoculation of F. verticillioides with other isolated fungi did not lead to a significant difference in disease severity, refuting the idea that other cellulolytic fungi can increase disease severity as an endophyte. This is the first report characterizing pathogenic F. verticillioides on sugarcane in southern China.