• 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.

• 한국균학회지
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• 제51권1호
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• pp.63-68
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• 2023

From June to August 2021, we surveyed diseases affecting beet (Beta vulgaris subsp. vulgaris) plants in Cheolwon, Hoengseong, and Pyeongchang regions in Gangwon Province, Korea. We observed severe leaf spot symptoms, such as brown to dark circular or irregular spots on the leaves, in plants. Disease incidence in the plant leaves in the fields investigated at the three locations ranged from 1 to 80%. Five single-spore isolates of Phoma sp. were obtained from the diseased leaves and identified as Neocamarosporium betae based on their cultural, morphological, and molecular characteristics. Three isolates of N. betae were subsequently tested to confirm their pathogenicity in beet plants via artificial inoculation. The tested isolates caused leaf spot symptoms in the inoculated plants, similar to those observed in the plants in the investigated fields. Therefore, our findings revealed N. betae as the pathogen causing beet leaf spot in Korea.

• Mycobiology
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• 제38권4호
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• pp.316-320
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• 2010

Leaf spot and blight disease was observed on two-year-old seedlings of Dendropanax morbifera (Korean name: Hwangchil tree) during July of 2008 in Jindo Island, Korea. Symptoms included yellow-brown to dark brown irregularly enlarged spots frequently located along the veins of leaves. The lesions were often surrounded by chlorotic haloes. Severe leaf blight and subsequent defoliation occurred when conditions favored disease outbreak. The causal organism of the disease was identified as Alternaria panax based on morphological characteristics and sequence analysis of the internal transcribed spacer region of rDNA. A. panax isolates induced leaf spots and blight symptoms not only on D. morbifera but also on the other members of Araliaceae tested. This is the first report of foliar blight caused by A. panax on D. morbifera.

• 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.

• The Plant Pathology Journal
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• 제22권4호
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• pp.375-380
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• 2006

In the survey from 1992 to 2000, twenty-eight parasitic diseases were observed in major apple producing areas in Korea. The predominant apple diseases were white rot(Botryosphaeria dothidea), Marssonina blotch(Marssonina mali), Valsa canker(Valsa ceratosperma), Alternaria leaf spot(Alternaria mali), and bitter rot(Collectotrichum gloeosporioides and C. acutatum). Apple scab that reappeared in 1990 after disappearance for 15 years was disappeared again since 1997. A viroid disease(caused by apple scar skin viroid) was newly found in this survey. The five diseases, fire blight(Erwinia amylovora), black rot(Botryosphaeria obtusa), scab(Cladosporium carpophilum), Monochaetia twig blight(Monochaetia sp.), and brown leaf spot(Hendersonia mali), which had once described in 1928 but no further reports on their occurrence, were not found in this survey. However, blossom blight(Monilinia mali), brown rot(Monilinia fructigena), and pink rot(Trichothecium roseum), which did not occur on apple after mid 1970s, were found in this survey.

• Weed & Turfgrass Science
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• 제3권2호
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• pp.121-129
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• 2014

본 연구에서는 2013년 잔디 재배지에서 발생하는 병해와 Rhizoctonia spp. 밀도를 조사하였다. 진주포장에서 갈색퍼짐병(Large patch)이 35% 발생하였고, 9월에 녹병이 발생하였다. 갈색마름병은 남해지역에서 9월과 10월을 거쳐 발생하였으며 7월 초 피시움잎마름병이 대발생 하였고, 동전마름병(Dollar spot)의 경우 전체 면적에 3%에 달하는 면적이 심각하게 피해를 입은 포장도 있는 것으로 조사되었다. 진주 대평에서 페어리링과 갈색퍼짐병이 발생하였다. 전북고창에서는 페어리링과 테이크올패치가 나타났으며 충북청주에서는 다수의 포장에서 갈색마름병이 관찰되었다. 경기평택에서는 갈색마름병, 도열병, 썸머패취, 커브라리아엽고병, 커브라리아엽고병과 녹조의 복합피해가 나타났다. 전염원 밀도는 장성, 진주, 산청과 남해지역 모두 시간이 지날수록 증가하는 것으로 나타났다. 병 발생과 병원균을 조사한 결과 골프코스에서 나타나는 병해와 유사한 것으로 나타났다.

• 한국균학회지
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• 제12권2호
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• pp.75-77
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• 1984

진주지방 vinyl house에서 자란 고추잎에 생긴 병반(病斑)을 채집하여 병원균(病原菌)을 분리(分離)하였다. 분리(分離)된 병원균(病原菌)의 분생자종(分生子種)의 길이 $40{\sim}150\;{\mu}m$ 폭은 $4.5{\sim}7\;{\mu}m$이고 $3{\sim}15$개가 총생으로 형성(形成)하며 분생포자(分生胞子)의 길이는 $40{\sim}185{\mu}m$이고 폭(幅)은 $4{\sim}5{\mu}m$이었다. 이 병원균(病原菌)은 PDA에서 늦게 자라고 포자(胞子)가 잘 형성(形成)되지 않으며 잎에 형성(形成)된 병반(病斑)을 습실처리하면 분생포자(分生胞子)가 잘 형성(形成)한다. 병원성검정(病原性檢定)을 위하여 만점에 생긴 분생포자(分生胞子)를 가지고 포자현탁액을 가지고 접종(接種)하였더니 고추의 잎과 엽병에 채집된 병징과 같은 개구리눈 모양을 한 병반(病班)이보였다. 고추에서 분리(分離)된 병원균(病原菌)은 분생자종(分生子種)의 모양과 크기 분생포자(分生胞子)의 길이와 병원성(病原性)에 의(依)하여 Cercospora capsici Heald et. Wolf 로 동정(同定)되었다.

• The Plant Pathology Journal
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• 제17권6호
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• pp.342-346
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• 2001

The physiological changes in sorghum (Sorghum vulgare Pers.) leaves infected with Drechslera sorghicola were investigated through five recognizable stages of disease development. Water-soaked yellowish brown spots developed two days after inoculation, turned brown with yellow halo, enlarged and coalesced at later stages of disease development. Healthy and infected leaves were analyzed for different biochemical constituents. The chlorophyll contents were decreased significantly with the progress of infection. The levels of reducing and total sugars increased while non-reducing sugars decreased to a significant extent with the progress of disease. The concentration of total phenolics, orthodihydroxy phenols, free and glycosidic phenols showed significant changes due to infection, whereas basic and acid phenols showed little or no change with disease development. Levels of phenolic compounds increased four days after inoculation and decrease thereafter, but the concentration was higher at every stage of disease development relative to healthy tissues. Polyphenol oxidase and peroxidase enzyme activities increased to varying degrees at different stages of infection. Analysis of protein fractions showed a significant increase with the progress of disease.

• 식물병과 농업
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• 제5권2호
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• pp.105-110
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• 1999

Bacterial leaf spot by Xanthomonas campestris pv. vesicatoria has been known to cause serious problem in red pepper in Korea. However recent survey showed that most smptoms in the leaves were mixed with two different symptoms one was leaf spot and the other was canker. bacteria isolated from canker were identified as Clavibacter michiganensis subsp. michiganensis on the basis of biochemical and physiological characteristics. The causal bacteria were non-motile rod-shaped and Gram-positive. The lesions on pepper leaves appeared at first as small blisters or pimple-like white spots which enlarged in size at a later stage. The centers of some of the spots became necrotic and brown and were surrounded by a white halo. Pathogenicity tests were performed on pepper cv. Alchan seedling by spraying of bacterial suspension. During 1997 and 1998 total 17% of 527 fields surveyed were infected by C. michiganensis subsp. michiganensis. The canker of red pepper caused by C. michiganensis subsp. michiganensis was first identified in this study in Korea, and new name "gueyangbyung" was tentatively given to the disease.

• 식물병연구
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• 제28권2호
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• pp.57-60
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• 2022

Leaves of Chionanthus retusus were found to be damaged by leaf spot disease associated with a fungus in Iksan, Korea. Leaf spots were angular to irregular, vein-limited, scattered, 1-8 mm diameter, brownish-gray to dark brown when dry, with heavy fructification. The pathogen causes premature defoliation of C. retusus plant and was identified as Pseudocercospora chionanthi-retusi based on morphological and molecular-phylogenetic analyses. The phylogenetic tree was constructed using multi-locus DNA sequence data of partial actin (actA), partial translation elongation factor 1-alfa (tef1), partial DNA-directed RNA polymerase II second largest subunit (rpb2) genes, and internal transcribed spacer regions. Current study provides detail morphological description of P. chionanthi-retusi on C. retusus in Korea, with supports of phylogenetic analysis and pathogenicity test.