• Proceedings of the Korean Society of Plant Pathology Conference
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• 2005.10a
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• pp.49-50
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• 2005

• Research in Plant Disease
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• v.12 no.1
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• pp.10-14
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• 2006

This study was carried out to know damages of the grapevine trees by the disease to the leaf spot from 2000 to 2003. The isolates collected from different varieties and locations were identified as Pseudocercospora vitis ($(L\acute{e}v)$.) Speg. based on the morphological and cultural characteristics. According to the in vitro test, the range of temperatures for the mycerial growth and the conidical germination of the fungus were from $10^{\circ}C\;to\;35^{\circ}C$ and optimum temperature was $25^{\circ}C$. There were remarkably different features between a low infection trees group and high infection trees group in terms of number of leaves per fruit branch, length and diameter of internode and leaf area.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2002.11a
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• pp.102.3-103
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• 2002

• The Korean Journal of Mycology
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• v.50 no.2
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• pp.131-136
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• 2022

Cornus officinalis plants that grow in several locations in Korea have been found to be infected with leaf spot disease. Symptoms include necrotic lesions, which are angular, irregularly shaped, vein-limited, and dark brown, on both sides of the leaves. The causal agent of the disease was identified to be Pseudocercospora cornicola based on the morphological characteristics of the fungus and molecular phylogenetic analysis of the obtained multi-locus DNA sequence data. This is the first report investigating P. cornicola found on C. officinalis in Korea.

• International Journal of Industrial Entomology and Biomaterials
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• v.22 no.1
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• pp.11-15
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• 2011

Impact of pruning date, shoot age and weather parameters on the severity and development of grey leaf spot (Pseudocercospora mori) of mulberry was studied. The disease severity (%) increased with increase in shoot age irrespective of pruning date. Maximum disease severity was observed in plants pruned during second week of October and minimum in plants pruned during last week of December. Significant (P<0.05) influence of date of pruning, shoot age and their interaction was observed on the severity of the disease. Apparent infection rate (r) was significantly higher during plant growth period from day-48 to day-55. Average apparent rate was higher in plants pruned during first week of September and least in plants pruned during third and fourth week of December. Multiple regression analysis revealed contribution of various combinations of weather parameters on the disease severity. A linear prediction model [$Y=66.05+(-1.39)x_1+(-0.219)x_4$] with significant $R^2$ was developed for prediction of the disease under natural epiphytotic condition.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.25-27
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• 2003

Since 1993, a total of 50 problematic plant diseases unrecorded in Korea were surveyed in Gyeongnam province. Totally 34 new host plants to corresponding pathogens investigated in this study were 5 fruit trees, 9 vegetables, 12 ornamental plants, 3 industrial crops, and 5 medicinal plants. Among the newly recorded fruit tree diseases, fruit rot of pomegranate caused by Coniella granati and Rhizopus soft rot of peach caused by Rhizopus nigricans damaged severely showing 65.5% and 82.4% infection rate. Among the vegetable diseases, corynespora leaf spot of pepper caused by Corynespora cassiicola and the crown gall of pepper caused by Agrobacterium tumefaciens, powdery mildew of tomato caused by Oidiopsis taurica were the most severe revealing 47.6%, 84.7%, and 54.5% infection rate in heavily infected fields, respectively. In ornamental plants, collar rot of lily caused by Sclerotium rolfsii, gray mold of primula caused by Botrytis cinerea, soot leaf blight of dendrobium caused by Pseudocercospora dendrobium, sclerotinia rot of obedient plant caused by Sclerotinia sclerotiorum showed 32.7 to 64.8% disease incidence. On three industrial plants such as sword bean, broad bean, and cowpea, eight diseases were firstly found in this study. Among the diseases occurring on broad bean, rust caused by Uromyces viciae-fabae and red spot caused by Botrytis fabae were the major limiting factor for the cultivation of the plant showing over 64% infection rate in fields. In medicinal plants, anthracnose of safflower caused by Collectotrichum acutatum was considered the most severe disease on the plant and followed by collar rot caused by Sclerotium rolfsii.(중략)

• Research in Plant Disease
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• v.12 no.1
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• pp.15-19
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• 2006

This study was carried out to know pathogenicity of the pathogen isolated in several location of Korea and penetration mechanism of the Pseudocercospora vitis ($(L\acute{e}v)$.) Speg. Inoculation tests at room temperature were performed on both sides of leaves with different isolates of the fungus. The typical symptoms appeared on the abaxial leaf surface, but no symptom was observed on the adaxial leaf surface with all isolates. The average incubation period was nine days, since all symptoms appeared from 8 to 10 days after inoculation. In order to know the mechanism of invasion of P. vitis to grapevine, the behavior of penetration hyphae through stomata were compared in two cultivars having different level of resistance. In order to know the mechanism of resistance of grape vine to P.vitis, two cultivars having different level of resistance were compared by counting the numbers and measuring size of the stomata per leaf. In a susceptible cultivar Campbell Early, the number of stomata was more than that of a resistance cultivar 'Kyoho'. In a susceptible cultivar 'Campbell Early', the fungus entered readily into stomata after inoculation. However, in a resistant cultivar 'Kyoho', the fungus seemed to pass over or surrounded only the guard cells. In comparison of height of guard cells of stomata between the two cultivars, significant differences were observed by scanning electron microscopy and light microscopy. The height of guard cells of 'Campbell Early' showed a little higher than those of 'Kyoho' known to be resistant to the fungus.

• Journal of Bio-Environment Control
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• v.24 no.2
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• pp.113-118
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• 2015

The objective of this experiment was to evaluate the effects of application wide plastic shelter (WPS) in the 'Campbell Early' grape. WPS was developed 30cm wider than standard plastic shelter (SPS; 210cm). Under the plastic shelter, the average daily temperature was $2{\sim}3^{\circ}C$ higher than ambient temperature, but WPS treatment was $0.5{\sim}1^{\circ}C$ higher than SPS treatment. However, relative humidity 15~20% lower than ambient and shown different result between two treatments annually. The occurrence of brown leaf spot disease caused by Pseudocecospora vitis on the vineyard decreased 55.6% (2012) and 17.2% (2013) under WPS than SPS. Grape bunches collected two harvest seasons (2012, 2013), were analyzed fruit quality (total soluble solid; TSS, titratable acidity; TA, berry weight, berry size). In 2012, grapes had no differences in the quality of two treatments, but in 2013, significantly increase $0.4^{\circ}Bx$ of TSS and decrease 0.8% of TA on the WPS than SPS. It suggests that the application WPS reduced the incidence of brown leaf spot disease annually, and then affect to the fruit quality.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.897-909
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• 2015

This study was conducted to evaluate the effect of weed control on disease incidence, plant growth and fruit quality, and to provide effective method to farmers at the vineyard. At the raincoat greenhouse cultivating 'Campbell Early', several weed controlling methods were compared to the control. Mean temperature of plots between soil covering (C.B., W.F., S.N., P.F. and R.H.) and non soil covering (M.W.2, M.W.3 and U.T.) were similar with $26.2^{\circ}C$ (July) and $25.8^{\circ}C$ (Aug.), but humidity of soil covering was sharply decreased in late-July under 40%. Soil water were all higher in soil covering plots than that of non-soil covering, however, soil temperature was recorded lower in soil covering plots. Disease incidence of Peudocercospora vitis according to soil coverings had effect on black plastic film mulching by decreasing grapevine leaf spot to 85% in July, 69% in August, compared to the control, with showing the smallest lesion incidence in FMB. Among growth characters, internode length and internode width of black plastic film mulching was higher than that of the control. SPAD value of black plastic film mulching was recorded the highest. It was not significant among the treatments, but brix was recorded highly in black plastic film mulching with $14{\sim}15^{\circ}Brix$.