• Research in Plant Disease
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• v.24 no.3
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• pp.175-181
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• 2018

Incidence rates of bacterial canker, bacterial leaf spot and postharvest fruit rot on the Korean yellow-fleshed kiwifruit cv. Haegeum were compared with those on the most popular green-fleshed kiwifruit cv. Hayward grown in several naturally infected kiwifruit orchards in 2013 and 2014. The percentages of diseased leaves caused by bacterial canker were 18.5% and 17.3% on Hayward in 2013 and 2014, but those on Haegeum were 1.2% and 0%, respectively. The percentages of diseased leaves caused by bacterial leaf spot on Hayward were 63.5% and 16.2% in 2013 and 2014, respectively, but no bacterial leaf spots were observed on Haegeum in both years. The average percentages of diseased fruits caused by postharvest fruit rot were 24.2% and 20.5% on Hayward in 2013 and 2014, while 6.3% and 4.4% and Haegeum, respectively. Botryosphaeria dothidea was turned out to be the major pathogen of postharvest fruit rot on both cultivars.

• Korean Journal of Veterinary Research
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• v.56 no.3
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• pp.147-153
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• 2016

A total of 782 blood and 465 tissue samples from 1,039 wild animals and 127 dairy goats were collected from January 2011 to December 2013 in 10 provinces of South Korea and tested for the presence of brucellosis. The Rose Bengal test revealed that 8.0% (52/650) of the serum samples were seropositive, while 4.2% (33/782) of the serum samples were positive for Brucella antibodies by competitive enzyme-linked immunosorbent assay. Of the 650 sera examined, only 16 (2.5%) were positive by both serological tests. Direct polymerase chain reaction (PCR) assay using B4/B5 primers for Brucella abortus (BCSP31) revealed the prevalence of Brucella to be 26.5% (129/487) in blood samples and 21% (98/465) in tissue samples while, 16S rRNA PCR detected Brucella DNA in 6.8% (33/487) and 2.6% (12/465) in blood and tissue samples, respectively. Of PCR-positive samples, only 6.2% (30/487) of blood samples and 2.4% (11/465) of tissue samples were found to be positive by both BCSP31 and 16S rRNA PCRs. However, Brucella strains were isolated by blood culture from only two out of 487 blood samples (0.4%). This characterization and identification of pathogenic Brucella isolates is the first to clearly indicate that the organisms were Brucella abortus biovar 1.

• The Plant Pathology Journal
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• v.36 no.5
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• pp.440-449
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• 2020

The purpose of this study was to analyze the genetic and pathogenic characteristics of Ralstonia pseudosolanacearum in roses in Korea, and to examine the similarities and differences between Korean isolates and the first-reported European strains. Between 2017 and 2019, seventeen isolates from rose plants were identified as R. pseudosolanacearum using Ralstonia-specific primers. All 17 isolates were identified as race 1 using race-specific primers, and were confirmed as biovar 3 due to their ability to utilize carbon sources. Multiplex PCR using phylotype discriminating specific primers identified the 17 isolates as phylotype I. Sequevar comparison with reference sequevars using the sequences of the egl, mutS, and fliC genes, and only the egl gene, revealed that the strains evaluated in this study corresponded to sequevar I-33. The pathogenicity in roses differed depending on the rose cultivars. The different methods used for the genetic characterization of R. pseudosolanacearum indicate that the 17 rose bacterial wilt isolates had the same genetic characteristics. The lack of genetic variation in these isolates indicates their recent introduction from other countries (likely European countries). Therefore, appropriate quarantine and control measures should be taken in order to avoid further increases in the pathogenicity and/or secondary host range of R. pseudosolanacearum through genetic mutation.

• Food Engineering Progress
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• v.14 no.4
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• pp.316-321
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• 2010

The efficacy of the ozonated water (0.1, 0.2, 0.4, 0.6, and 1.0 ppm) in reducing the risk of food-borne disease was investigated in this study. After inoculation of Listeria monocytogenes (ATCC 19112), Salmonella enterica subsp. enterica biovar Typhimurium (ATCC 12598), Escherichia coli O157:H7 (ATCC 43890) to lettuce, spinach, and beef, inhibition effect with different washing concentrations, time, and methods with ozonated and tap water were evaluated. As a result, there were 2.16 to 3.85 log CFU/mL reduction in different foods and 7 log CFU/mL reduction on cutting boards after watering with ozonated water. Higher than 0.2 ppm of ozonated water treatment reduced the growth of food-borne disease bacteria with increasing washing time and ozone concentration. These results suggested that the ozonated water treatment effectively improved the microbiological quality and food safety.

• Research in Plant Disease
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• v.24 no.2
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• pp.123-131
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• 2018

Kiwifruit has been cultivated in southern coastal regions of Korea since late 1970s. New cultivars have been successively released in recent years. In this study, we investigated major disease and pest incidences in new kiwifruit cultivars 'Goldone', 'Redvita' and 'Garmrok' at open field in Sacheon for 3 years and rain-proof field in Jeju for 2 years. For the bacterial canker, the 3 new cultivars showed more disease occurrence in Sacheon but rare in Jeju. For leaf spot disease, compared to disease incidence of 20% on 'Hayward' in Sacheon, cv. 'Garmrok' had high incidence about 60% but cv. 'Goldone' and cv. 'Redvita' had low incidence less than 20%. However, in Jeju, diseases incidences of all the new cultivars were lesser than 20%. In the case of Hemiptera, many Halyomorpha halys and Nezara antennata appeared in Sacheon but in Jeju Plautia stali was dominated. Isolated bacterial canker pathogen was identified as Pseudomonas syringae pv. actinidiae biovar 3. Leaf spots pathogens were Phomopsis sp., Phoma sp., Fusarium tricinctum and Alternaria alternata. This study shows the disease information on new kiwifruit cultivars and the adequate disease managements will be required.

• Korean Journal of Poultry Science
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• v.35 no.1
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• pp.9-13
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• 2008

Salmonella enterica serotype gallinarum biovar Gallinarum or Pullorum and Salmonella enterica serotype Enteritidis are the most important diseases in poultry industry. Transitional diagnosis methods of these diseases such as direct isolation and identification by a biochemical test are time consuming with low specificity. In this study, we have focused on the suitable procedure for the rapid and accurate diagnosis of diseases derived from the three Salmonella strains. We initially confirmed Salmonella species by PCR using a specific ITSF/ITSR primer pair instead of biochemical test, and then the PCR-amplified phase 1 flagellin (fliC) using a specific fliCF/fliCR primer pair was digested with a restriction endonuclease, Bpm I and/or Bfa I, to discriminate among S. Pullorum, S. Gallinarum, and S. Enteritidis. We found that these methods could be applied to field isolates of the three Salmonella strains to detect and to discriminate rapidly for convenient diagnosis.