• Journal of the korean veterinary medical association
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• v.25 no.5
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• pp.282-291
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• 1989

Incidence of infectious bronchitis virus(IBV) infection in vaccinated breeder chickens was investigated by hemagglutination inhibition(HI)test for IBV using Mass 41 antigen. In the breeder chickens with the reduced egg production. chalky deposit. wrinkled

• Proceedings of the Korean Society of Life Science Conference
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• 2002.03a
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• pp.74-74
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• 2002

• The Korean Journal of Mycology
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• v.48 no.3
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• pp.325-328
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• 2020

Damping-off symptoms were frequently observed on young plants of edible amaranth (Amaranthus mangostanus) grown in vinyl greenhouses by farmers located in Goyang and Yangpyeong in Korea during disease surveys carried out in 2019 and 2020. The incidence of the disease was 1-20%. A total of eight isolates of Rhizoctonia sp. were obtained from the stems of the diseased plants. All the isolates were identified as Rhizoctonia solani AG-4, based on the morphological characteristics and anastomosis test. Three isolates of R. solani AG-4 were tested for pathogenicity on edible amaranth by artificial inoculation. All the tested isolates of R. solani AG-4 induced damping-off symptoms on the inoculated plants; these symptoms were similar to those observed on the vinyl greenhouse plants surveyed. This is the first report of R. solani AG-4 causing damping-off in edible amaranth.

• The Korean Journal of Mycology
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• v.48 no.4
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• pp.519-521
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• 2020

Damping-off symptoms were frequently observed on young plants of Indian lettuce (Lactuca indica) grown in a farmer's vinyl greenhouse located in Goseong, Gangwon province of Korea during a disease survey in June 2019. The incidence of diseased plants in the vinyl greenhouse investigated was 30-50%. Four isolates of Rhizoctonia sp. were obtained from the diseased plants and identified as Rhizoctonia solani AG-4 based on the morphological characteristics and anastomosis test. Three isolates of R. solani AG-4 were tested for pathogenicity on Indian lettuce by artificial inoculation. All the tested isolates induced damping-off symptoms on the inoculated plants. The symptoms were similar to those observed in plants from the farmer's vinyl greenhouse investigated. This is the first report of R. solani AG-4 causing damping-off in Indian lettuce.

• Research in Plant Disease
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• v.27 no.1
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• pp.45-47
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• 2021

Damping-off symptoms were frequently observed on young plants of coastal hogfennel (Peucedanum japonicum) grown in a farmer's vinyl greenhouse located in Goseong, Gangwon Province, Korea during a disease survey in June 2019. Incidence of the diseased plants was 50-70% in the vinyl greenhouse investigated during the disease survey. Eight isolates of Rhizoctonia sp. were obtained from the diseased plants. All the isolates were identified as Rhizoctonia solani AG-4 based on the morphological characteristics and anastomosis test. Three isolates of R. solani AG-4 were tested for pathogenicity on coastal hogfennel by artificial inoculation. All the tested isolates induced damping-off symptoms on the inoculated plants. The symptoms were similar to those observed in the farmer's vinyl greenhouse investigated. This is the first report of R. solani AG-4 causing damping-off in coastal hogfennel.

• The Korean Journal of Mycology
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• v.50 no.1
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• pp.61-64
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• 2022

In July and September 2020, a severe outbreak of stem rot was observed on bonnet bellflower (Codonopsis lanceolata) plants in a farm located in Chuncheon, Gangwon Province, Korea. The symptoms initially appeared on the stem at or above the soil line. Later, the infected stem completely rotted and blighted. The incidence of diseased plants in the field was 2-30%. Ten isolates of Rhizoctonia sp. were obtained from the stem lesions of diseased plants. All isolates were identified as Rhizoctonia solani AG-4 based on the morphological characteristics and anastomosis test. Three isolates of R. solani AG-4 were tested for pathogenicity on bonnet bellflower plants through artificial inoculation. All tested isolates induced stem rot symptoms on the inoculated plants. The symptoms were similar to those observed in plants from the farm. This is the first report of R. solani AG-4 causing stem rot in bonnet bellflower.

• The Korean Journal of Mycology
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• v.50 no.3
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• pp.249-254
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• 2022

In June 2021, foot rot symptoms were observed in wasabi (Eutrema japonicum) plants growing in vinyl greenhouses of the Alpine Agricultural Experiment Station, Wild Vegetable Research Institute, in Taebaek, Gangwon Province, Korea. Diseased plants displayed black soft rot of crowns and petioles at the soil line and wilted. The incidence of diseased plants was 2-10% in four out of five vinyl greenhouses investigated. Eight fungal isolates were obtained from diseased plants. All the isolates were identified as Phytophthora pseudocrytogea based on their morphological characteristics and phylogenetic analysis. Three isolates of P. pseudocrytogea were used for pathogenicity test on wasabi plants via artificial inoculation. The pathogenicity of the isolates was confirmed in the inoculated wasabi plants. The symptoms shown by the inoculated plants were similar to those observed in plants from the investigated vinyl greenhouses. This is the first report of P. pseudocryptogea causing Phytophthora foot rot in wasabi.

• Research in Plant Disease
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• v.21 no.1
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• pp.20-23
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• 2015

A sequential planting method was developed to screen rice plants with durable resistance against rice blast in a short time, and applied for several years in Korean rice breeding program. In this study, we showed the advantages of a sequential planting method compared to other pathogenicity tests. The correlation analysis among three pathogenicity tests and other factors demonstrated that durable resistance depended on the average of diseased leaf area and the number of compatible pathogens. Significant correlations were found in the nursery test but not in the field test result. In addition, we traced changes in the pathogen population during sequential planting stages through re-isolation of the pathogen. The portion of compatible pathogens was increased during sequential planting. Through this study, we provide an effective sequential planting method and direction of durable resistance in a breeding program.

• Plant Resources
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• v.2 no.2
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• pp.81-87
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• 1999

Sixteen isolates showing relatively strong antagonicity against the ginger rhizome rot pathogen, Pythium zingiberum, were selected among the 155 isolates from ginger rhizome surfaces and rhizospheres of ginger cultivation fields in Wanju, Chonbuk. The isolate, 'HB 26-5'showing the strongest antagonicity was finally selected by testing duration of inhibition effect and pathogenicity to ginger. The isolated antagonistic microorganism, 'HB 26-5' was rod shape, gram positive and formed endospore. The isolate produced acids utilizing glucose, arabinose, xylose and mannitol, and acetoin at VP test, and grew anaerobically. Temperature range for growth was from 10 to 4$0^{\circ}C$ . Reaction to catalase and gelatin, hydrolysis were positive, and casein hydrolysis and indol production were negative. Based on the mycological characters and the fatty acid composition, it was identified as Bacillus polymyxa. The pathogenicity test of isolated Bacillus polymyxa 'HB 26-5'on 22 crop cultivars resulted that only the lettuce was influenced in germination, and the others were not affected.

• The Korean Journal of Mycology
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• v.48 no.4
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• pp.511-518
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• 2020

This study was conducted to isolate and identify the fungal pathogen caused unreported post-harvest disease on apples (cv. Fuji) fruit in Korea. The disease symptoms on apples appeared as irregular, light to dark brown, slightly sunken spots. The three fungal strains were isolated from infected tissues of apple fruits and their cultural and morphological characteristics were completely consistent with those of Plenodomus collinsoniae. The phylogenetic analysis using the internal transcribed spacer (ITS) regions, beta-tubulin (TUB), and the second largest subunit of RNA polymerase II (RPB2) sequences revealed the closest relationship of the isolates with Plenodomus collinsoniae at the species level. The pathogenicity test showed the same dark brown spots on Fuji apple cultivar. Therefore, P. collinsoniae is a newly reported fungal agent causing post-harvest disease on apples in Korea.