• The Korean Journal of Mycology
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• v.42 no.3
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• pp.183-190
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• 2014

Apple blotch is a major apple disease and recently it causes critical economic losses in apple orchards in Korea. In this review, we described the history of apple blotch researches, ecology and life cycle of Marssonina coronaria, cultural and molecular characteristics and simple isolation method as well. Furthermore, characteristic of apple blotch like symptoms, its cause still unknown, occurs frequently in cv. "Fuji" was described in detail.

• Agrochemical news magazine
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• v.19 no.4 s.145
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• pp.44-45
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• 1998

• Korean Journal Plant Pathology
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• v.3 no.4
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• pp.285-290
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• 1987

Septoria brown spot caused by Septoria glycines Hemmi is one of the serious fungal diseases in soybean. Since little has been known about the disease progress in the field, the present study was conducted to determine the factors affecting the disease progress in the soybean plant. Disease severity and pattern of the progress of the Septoria brown spot were different with varieties. Susceptibility of soybean plants increased with increase of plant age and leaf maturity in order from the primary leaf to the newly expanded leaf. It seemed to be related with conidial germination on the leaves. Germination and germtube elongation were more inhibited by the diffusates obtained from upper leaves than those from lower leaves and they were higher in a susceptible variety than in a moderately resistant one.

• Research in Plant Disease
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• v.21 no.4
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• pp.261-267
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• 2015

During the period from 2013 to 2014, disease occurrences by various pathogens in apple cultivars have been investigated in northern Gyeongbuk province of Korea. Anthracnose, white rot, Alternaria leaf spot, Marssonina blotch, and bacterial shoot blight as major diseases have been observed. Pathogens isolated from the symptomatic plants were identified as Colletotrichum gloeosporioides for anthracnose, Botryosphaeria dothidea for white rot, Alternaria alternata for Alternaria leaf spot, Marssonina mali for Marssonina blotch, and Pseudomonas syringae pv. syringae for bacterial shoot blight. Of all diseases, the bacterial shoot blight has been severely increased in chronically infested fields in Gyeongbuk province.

• Korean journal of applied entomology
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• v.22 no.1 s.54
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• pp.7-14
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• 1983

Septoria brown spot closed by Septoria glycines is one of the most serious fungal diseases in soybean. Average yield reduction of 3 varieties for two years was $16.1\%$ by the septoria brown spot inoculation and $9.0\%$ by the natural infection as compared to fungicide-sprayed plots. Number of pods per plant and seed weight were significantly reduced while plant height, number of branches and number of nodes per plant were not affected. Yield reduction was positively correlated to the septoria brown spot severity in all varieties examined. Correlation coefficient $(r=0.38^*)$ between yield reduction and area under the disease progress curve was higher than that (r=0.156) between yield reduction and Van der Plank's apparent infection rate. Potential effect of the septoria brown spot on the soybean yield reduction estimated with the area under the disease progress curve was expressed by the equation of Y=4.38+0.05X $(r=0.0696^*,\;df=25)$.

• Current Research on Agriculture and Life Sciences
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• v.16
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• pp.84-95
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• 1998

Apple Marssonina blotch, caused by Diplocarpon mali, which has been increasing on apple trees and become one of the most serious diseases on apple trees in Korea since the begining of 1990's. In this study, ecology of Marssonina blotch including disease incidence and spore dispersals was surveyed from 1992 to 1995 in Kyungpook, and factors influencing the incidence of the disease were analyzed. Marssonina blotch began to occur on apple leaves in June and was observed commonly in most of apple orchards after August, and increased rapidly in September. The incidence of this disease was high at the year of low temperature and a lot of precipitation. The conidia discharge began to occur in May and continued to October, and the peak period of spore release was in August and usually more than 70% of total spore release of the year released from August to September. The incidence of the disease was high in the northern and mountain are as such as Yeongjoo, Chungsong, Andong, and relatively low in the southern areas such as Kunwi, Yongchon. Jonathan cultivar was the most susceptible to Marssonina blotch, and Jonagold, Sekaiichi was secondly susceptible and the next Fuji was more susceptible than Tsugaru. The incidence of the disease was relatively high in orchards which cultivation management of irrigation, drainage, air circulation, fertilization, and fungicide spraying were poor.

• Korean Journal Plant Pathology
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• v.11 no.2
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• pp.120-131
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• 1995

이 연구는 우리나라의 유용 자원식물에 발생하는 진균성 미기록 병해에 대한 두 번째 보고이다. 10가지 병해에 대한 각각의 병징, 병 발생환경, 병원균, 그리고 몇 가지 병리학적 소견을 기록하였다. 동자꽃 갈색 무늬병은 장마철부터 발생하여 심한 잎마름을 일으켰으며, 병원균은 Septoria lychnidis로 동정되었다. 산박하 모무늬병은 장마철에 심하게 발생하고 작은 모무늬가 합쳐져 잎의 한쪽이 검게 고사하였는데, 병원균은 Septoria plectranthi로 동정되었다. 좀명아주 갈색 무늬병은 여름부터 가을까지 흔히 발생하여 조기낙엽을 일으켰으며, 병원균은 Cercospora dubia로 동정되었다. 나팔꽃 점무늬병은 장마철부터 가을까지 흔히 발생하여 관상가치를 떨어뜨렸는데, 병원균은 Cercospora ipomoeae로 동정되었다. 돌콩 점무늬병은 장마철부터 가을까지 계속 발생하여 생육을 크게 저해하였는데, 병원균은 Pseudocercospora ligustri로 동정되었다. 박주가리 뒷면곰팡이병은 여름부터 가을까지 흔히 발생하여 조기낙엽과 황화를 일으켰는데, 병원균은 Passalora miurae로 동정되었다. 고려엉겅퀴 흰가루병은 여름부터 발생하여 묵나물의 수향과 품질에 피해를 주었는데, 병원균은 Sphaerotheca fusca로 동정되었다. 왜당나귀흰가루병은 국지적으로 발생하여 생육을 저해하고 어린 묘는 고사시켰는데, 병원균은 Erysiphe heraclei로 동정되었다. 가래나무 점무늬병은 장마철에서 가을까지 발생하여 잎마름을 유발하였는데, 병원균은 Sphaerulina juglandis로 동정되었다.

• Agrochemical news magazine
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• v.15 no.1 s.118
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• pp.52-57
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• 1994

• Research in Plant Disease
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• v.24 no.4
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• pp.249-256
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• 2018

Disease occurrence in apple cultivars on 13-30 apple orchards from April to October 1992-2010 was investigated at 30 days intervals in Gyeongbuk, Gyeongnam and Jeonbuk provinces of Korea. Apple cultivar 'Fuji' was found most susceptible and is being damaged by cedar apple rust, scab, gray mold, Alternaria blotch and Marssonia blotch as major leaf diseases that were observed. The percentage of occurrence of these leaf diseases varies from every year. This variation is based on different rainfall and temperature conditions, cultivation, root stock and changed system of fungicide spray during the particular year and season.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.773-786
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• 2016

Grape cultivar "Campbell Early" account for 70% of table grape in Korea and Leaf Spot Disease caused by Pseudocercospora vitis is one of a major disease in greenhouse and field grown area during late summer season in both of organic and conventional grape farm. Leaf spot disease can cause lowing of sugar content in fruit and vine growth and very difficult to control especially in organic field. Photosynthesis ability and chemical components are compared between leaf spot disease infected leaves with degree of necrotic area. With increase of disease necrotic area, $CO_2$ differential value, water use efficiency and $CO_2$ assimilation and respiration ratio are decreased proportionally and on the other hand, stomatal conductance value is not affected by disease necrotic area. Chlorophyll contents are also decreased by 50% in heavily infected leaves and imply decrease of chlorophyll contents is a major source of photosynthesis ability decline. With increase of disease necrotic area in leaves, total nitrogen and phosphate contents are decreased and on the other side, total carbon, potassium, calcium and magnesium contents are increased. From this research, we can infer that not only chemical control program is important in control of leaf spot disease but also fertilizing program is significant especially in organic agronomical control of fungal disease in grape cultivar "Campbell Early".