• Research in Plant Disease
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• v.9 no.1
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• pp.21-24
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• 2003

In May of 2002, the gray mold disease occurred severely on broad bean (Vicia faba) grown in farmer's fields located in Changseon-myon, Namhae-gun, Gyeongnam provice, Korea. The infected leaves, at first, discolored to gray or dark from the tip, and eventually died. Conidia of the fungus in mass were hyaline or gray, 1-celled, mostly ellipsoid or ovoid and sized 6~22$\times$4~16 ${\mu}{\textrm}{m}$. Thick conidiophores were formed on PDA with 15~37 ${\mu}{\textrm}{m}$ in width. The sclerotia were readily formed potato-dextrose agar and optimum temperature for sclerotial formation was 2$0^{\circ}C$. Pathogenicity of the causal organism was proved according to Koch's postulate. The causal organism was identified as Botrytis cinerea based on its mycological characteristics. This is tile first report on gray mold of broad bean (Vicia faba) caused by Botrytis cinerea in Korea.

• Research in Plant Disease
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• v.14 no.1
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• pp.10-14
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• 2008

Batcterial wilt caused by Ralstonia solanacearum is one of important and widespread diseases worldwide as well as in Korea. Bacterial wilt disease caused by R. solanacearum has been reported mainly in solanaceous crops including eggplant (Solanum melongena), tomato (Solanum lycopersicum), potato (S. tuberosum), and pepper (Capsicum annuum). A total of 48 strains of R. solanacearum from eggplant were collected during 2005 and 2006. They were confirmed as R. solanacearum by PCR amplification with primer pair flipcF/flipcR resulting in production of 470-bp DNA fragment. The 15 isolates exhibited pathogenicity on eggplant and tomato, but less virulent on pepper than other species. The biovar of collected isolates, which have been reported of five types worldwide, were classified as biovars 3 and 4 by physiological test. Biovar 4 was the dormant type without pathogenicity on eggplant rootstock, whereas biovar 3 had pathogenicity on eggplant rootstocks that is resistant to R. solanacearum, indicating necessity of breeding new rootstock with resistance to R. solanacearum biovar 3

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.258-262
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• 2008

The experiment was conducted to investigate the potential for environmentally friendly cultivation of cv. Haryeong, which was bred by the National Institute of Highland Agriculture in 2006, through evaluation of the late blight field resistance at the farmer's practices level. cv. Haryeong showed higher field resistance to late blight as 590.3 in mean Area Under the Disease Progress Curve (AUDPC) during the cultivation period than cv. Superior as 1377.7 in AUDPC. However there was no observed different trend among the experimental treatments. Mean of tuber yield of cvs. Haryeong and Superior were 2,870 kg/10a and 2,301 kg/10a, respectively, and in all experimental treatments Haryeong was 25% higher than those of Superior. Mean of dry matter content of Haryeong and Superior were 18.1% and 16.1%, respectively, and there were no significant differences among the experimental treatments. cv. Haryeong was confirmed as a suitable cultivar for environmentally friendly cultivation in this experiment. In the future, additional research on fertilization and disease management will be required.

• Research in Plant Disease
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• v.27 no.3
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• pp.115-119
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• 2021

Sclerotinia rot was occurred on the leaf and stem of Peucedanum japonicum Thunb. in greenhouse field of Pohang city of Gyeongbuk province in Korea. The typical symptom of the disease was light brown spot and tipburn on infected leaves. The colony of the isolated fungus was white to light gray in color. Asci were cylindrical shape and 75-240×5.9-17.3 ㎛ in size. Apothecia were cup-shaped with numerous asci and 0.5-0.9 cm in size. Ascospores were aseptate and ellipsoid in shape, and 8.4-10.7×4.8-5.8 ㎛ in size. Sclerotia formed on the plants and potato dextrose agar medium were globose to irregular in shape and black in color. Partial sequencing of rDNA of this isolate showed that it was 100% consistent with that of Sclerotinia sclerotiorum. It was confirmed that the same lesion was formed by reinoculating this pathogen on a healthy P. japonicum Thunb. and the same strain was isolated. This is the first report on the Sclerotinia rot of P. japonicum Thunb. caused by S. sclerotiorum in Korea.

• Journal of Oral Medicine and Pain
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• v.46 no.2
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• pp.33-40
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• 2021

Purpose: Oral candidiasis is the most common fungal infection in the oral cavity which is usually diagnosed from clinical findings. A retrospective study was conducted to identify risk factors for oral candidiasis and to characterize the demographic and clinical features of affected patients. Methods: From January 1, 2019 to December 31, 2019, it consisted of 90 oral candidiasis patients diagnosed based on clinical finding and treated with antifungal drugs. As a retrospective study of those people, surveys were conducted on sex, age, systemic disease, a use of dentures, complaints of dry mouth, smoking and alcohol consumption, culture on potato dextrose agar (PDA) medium, culture on chromogenic agar (CA) medium and a duration of antifungal treatment. Results: Among 90 selected patients, the male and female ratio was 41:49. Overall, female had a higher infection rate than male in all age groups. In this study, oral candidiasis was not clearly susceptible to dry mouth, smoking or drinking, wearing dentures and association with systemic disease. Among 90 patients with oral candidiasis, 83 had colonies formed on PDA medium and 53 had colonies formed on CA medium. The duration of antifungal treatment was highest between 5 and 8 weeks. In addition, there was statistical significance between the culture results in CA medium and the duration of antifungal treatment. Conclusions: Generally, old age or infants, dry mouth, smoking, a use of dentures and endocrine abnormalities are risk factors to increase oral candidiasis; however, in this study, it was mainly found in the elderly aged 60 or older regardless of sex and the incidence of oral candidiasis was not obviously related with patients with dry mouth, smoking or drinking, denture wearers and endocrine abnormalities. Interestingly, when the fungi were cultured in CA medium, the duration of antifungal treatment was increased.

• The Korean Journal of Mycology
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• v.52 no.2
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• pp.145-153
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• 2024

While investigation of the fungal diseases on apples collected from Cheongsong-gun and Bonghwa-gun in Gyeongbuk province, Korea, between August and September 2023 isolated five fungal strains from fruits with sooty blotch and flyspeck (SBFS) disease. The strains were designated as KNUF-23-CS02, KNUF-23-CS-06, KNUF-23-CS12, KNUF-23-BH01, and KNUF-23-BH03. When grown on potato dextrose agar and 2% water agar, the cultural characteristics of the strains were similar to those previously reported characteristics of Peltaster fructicola Pf001. The strains produced monoblastic, hyaline conidiogenous cells; the conidia were hyaline, unicellular, cylindrical to ovoidal, and 3.5-7×1.7-3.9 and 4.0-6.6×1.8-3.2 μm in size on synthetic nutrient-poor agar or water agars, respectively. Secondary conidia production by microcyclic conidiation and budding was observed. The KNUF-23-BH03 strain was shown to cause SBFS symptoms similar to those observed on the apples in the pathogenicity test. Molecular phylogenetic analyses were conducted based on the isolated species sequences of the internal transcribed spacer region, nuclear large ribosomal DNA subunit, and mitochondrial small ribosomal RNA subunit gene. The five strains were clustered with Peltaster fructicola Pf001. Based on the cultural and morphological characteristics and phylogenetic analysis, the five strains were identified as Peltaster fructicola, which has not been previously reported in Korea.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.4
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• pp.405-415
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• 2014

Objectives: The aim of this study is to comprehensively summarize endotoxin levels reported in operations using metalworking fluids(MWFs). Methods: An extensive literature review was conducted of studies reporting endotoxin levels in processes using metalworking fluids. Keyword search terms included 'metalworking fluids', 'machining fluids', 'metalworking operation', 'machining operation' and 'endotoxin', which were used in combination. Results: A total of ten manuscripts were found to report on airborne endotoxin levels from metalworking operations in the automobile industry. Polycarbonate(PC), polyvinyl chloride(PVC) and mixed cellulose ester(MCE) were used to collect airborne endotoxin. Limulus Amebocyte Lysate was mainly used to quantify endotoxin amount. The levels of airborne endotoxin reviewed varied considerably, ranging from < $4EU/m^3$ to $790EU/m^3$, which was found to be far lower than those from cotton and potato processing plants, sawmills, and poultry farms. Several studies assumed that exposure to endotoxin could be a causative agent of respiratory diseases. Conclusions: Inhalation endotoxin exposure levels reported from metalworking operations were found to be lower than those from industries handling organic materials, even though it could be considered as a possible cause for several respiratory diseases.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.347-349
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• 2001

Black blights attacked the blossom and flower buds of wild chrysanthemum (Chrysanthemum boreale) in the experimental field in Hamyang in 1998. The infection rate of the disease on the plant ranged from 4.0 to 91.8%. The pathogen isolated from the infected flower buds produced numerous conidia in pycnidia. The pycnidia, which were immersed into the petals, emerged through the epidermis by short ostiolate neck. Conidia had 0-3 septate (mostly uniseptate) and were 10-27.5 $\times$5-7.5 ㎛ in size. The fungus produced pseudothecia on potato dextrose agar (PDA), and uniseptate ascospores produced in asci were 10$\times$2.7 ㎛ in size. The pathogen also produced pycnidia and pycnidiospores on PDA after 4 weeks in the dark condition. The conidia produced on PDA were smaller than those from infected plants. Based on the examined mycological characteristics, the fungus was identified as Didymella chrsanthemi.

• Research in Plant Disease
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• v.22 no.2
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• pp.116-121
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• 2016

In 2015, stem blight of Rubus crataegifolius was observed in Pohang, Korea. The symptoms began as dark red spots in the stem, which led to stem blight, then leaf blight, and eventually resulted in death. A fungal isolate was obtained from a symptomatic stem and incubated on a potato dextrose agar plate. The isolated fungus produced white, cloudy mycelia turned black in 3 days. Based on the morphological characteristics, the causal fungus was assumed to be Botryosphaeria sp. A pathogenicity test was conducted according to Koch's postulates. To identify the causal agent, the combined sequence of the internal transcribed spacer, ${\beta}$-tubulin, and translation elongation factor $1{\alpha}$ genes were used for phylogenetic analysis. Approximately 1,200 bp of the combined sequence clearly suggested that the isolated pathogen was Botryosphaeria parva. This is the first report on stem blight in R. crataegifolius caused by B. parva in Korea.

• Korean Journal of Veterinary Research
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• v.50 no.4
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• pp.323-326
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• 2010

Candidiasis is a mycosis caused by the mycelial yeast of the Candida genus which is opportunistic pathogen of humans, animals, and birds. Under some conditions such as prolonged antibiotic therapy, overcrowding, and immunosuppression, the opportunistic Candida can cause disease. Chicken candidiasis is sporadically occurred and characterized by unsatisfactory growth, listlessness, roughness of feathers, and death. A case of 23 weeks old layer with history of increased mortality and anemia was submitted to our Lab. At necropsy, the characteristic lesions were observed in the crop and proventriculus. The whitish pseudomembrane, that are peeled easily, was found in the crop. Proventriculus was swollen and the mucosa was covered with hemorrhagic exudate. The histological changes of the affected crop are epithelial hyperplasia, hydropic degeneration, and mycelia formation. Smears made from the necrotic mucosal surfaces of the crop revealed the presence of large number of yeast cells and mycelia. Pure cultures of yeast colonies were obtained from the potato dextrose agar. The yeast cells were identified as Candida albicans by gene sequencing. To our knowledge, this is the first report of candidiasis in chickens with anemia in Korea.