• 식물병연구
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• 제14권1호
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• pp.68-70
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• 2008

2006년 6월 전남 순천과 고흥지역의 농가에서 재배되고 있는 참다래 잎에 갈색 점무늬 증상이 나타나기 시작하여 점차 짙은 갈색의 둥근 무의로 확대되었고, 심할 경우에는 생육기 동안에도 낙엽을 초래하였다. 둥근 무늬병반에서 일관성 있게 분리된 Alternaria sp.를 순수배양시켜 관찰한 균학적 특징과 참다래 잎에 상처접종에 의한 확인된 병원성을 토대로 Alternaria alternata (Fr.) Keissler에 의한 참다래 갈색둥근무늬병으로 동정하였다. A. alternata는 감자한천배지에서 짙은 회색 균총을 형성하였고 분생포자를 다량 형성하였다. 담갈색 또는 금색의 분생포자는 난형 또는 역곤봉 형태를 하며, 분생포자경 위에 보통 5개 이상 사슬모양으로 형성되는데, 횡격막이 $3{\sim}5$개, 종격막이 $1{\sim}2$개가 있고, 분생포자의 크기는 $16.5{\sim}42.1{\times}6.7{\sim}19.5\;{\mu}m$, 분생포자경의 길이는 $8.6{\sim}112.7\;{\mu}m$였다. 이상과 같이 국내 최초로 A. alternata에 의한 참다래 갈색둥근무늬병의 발생을 보고하는 바이다.

• The Plant Pathology Journal
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• 제24권2호
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• pp.125-130
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• 2008

Various kinds of leaf spots and blights were found in kiwifruit (Actinidia deliciosa) orchards on 2006 in Korea. Disease incidences were quite variable between open-field and rain-proof shelter. Rate of diseased leaves was recorded as about 70% at open-field orchards in late season but use of rain-proof vinyl shelters alleviated the disease incidences by 20%. Angular leaf spots appeared at early infection stage on June and several other symptoms were also recognized as the disease developed afterward. On September, brown leaf blights were the most frequent, followed by grayish brown ring spots, silvering gray leaf blights, zonate leaf blights, dark brown ring spots and angular leaf spots at open-field orchards. Four fungal species were frequently isolated from the disease symptoms. Phomopsis sp. was the most predominant fungus associated with the leaf spot and blight symptoms on kiwifruit, followed by Glomerella cingulata, Alternaria alternata and Pestalo-tiopsis sp. Phomopsis sp. was commonly isolated from angular leaf spots, silvering gray leaf blights, and zonate brown leaf blights. G. cingulata, A. alternata and Pestalotiopsis sp. were isolated from grayish brown ring spots (anthracnose), brown ring spots and zonate dark brown leaf blights. Typical symptoms appeared on the wounded and unwounded leaves, which were inoculated by each of Phomopsis sp., G. cingulata, and Pestalotiopsis sp., but A. alternata caused symptoms only on the wounded leaves.

• 식물병연구
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• 제19권4호
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• pp.300-307
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• 2013

This study was conducted to determine the occurrence of leaf rot and leaf ring spot, caused by Rhizoctonia solani in Chinese cabbage under seedling nursery and cultivation greenhouses. Symptoms of leaf rot and leaf ring spot were found in three Chinese cabbage cultivars, Brassica campestris subsp. pekinensis, 'Ryeokgwang', 'Daetong', and 'CR mat'. In Hwacheon, the disease incidence was 73.8% in the seedling stage of the Chinese cabbage. In Icheon, the symptoms were observed on the upper leaves of the Chinese cabbage cultivar, 'Norangmini' with 20.5% of disease incidence. The symptoms appeared as primary lesions consisting of small, circular necrotic ring spots with gray color, 1.4-3.0 mm in diameter, accompanied by secondary rot lesions with large irregular borders of leaves. The color of mycelial mat of 20 isolates was dark brown and light brown. The average hyphal diameter of all the isolates was within 5.01-11.12 ${\mu}m$. Among the 20 strains isolated from Chinese cabbage, 16 isolates and four isolates anastomosed with the AG-1 (IB) and AG-1 (IC), respectively. Twenty isolates tested were only virulent on foliage parts of Chinese cabbage leaves but were avirulent on stem parts of the plants. Based on the mycological characteristics and pathogenicity test on host plants, the fungus was identified as Rhizoctonia solani.