• Korean Journal Plant Pathology
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• v.2 no.3
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• pp.185-192
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• 1986

Upon germination, a conidium was septated in accordance with number of germ tubes. The percentages of ppressorial formation were not different between the resistant cultivars (Kumchang NO. 2 and Hongilpum) and the susceptible cultivars (Haneulcho and Saegochu). Appressorial form was various such as round, elliptic or star-shapped. The maximum number of appressoria was shown at 12 hours after inoculation. By 24 hours fter inoculation, hypersensitive tiny brown lesions were observed on the leaves and fruits of the resistant cultivars. Epidermal cells under cuticle layer of the resistant Kumchang NO. 2 fruit showed severe plasmolysis, while on the susceptible cultivars, the lession was largely extended to following incubation. Subcuticular infection hyphae were profusely colonized in the disintegrated tissues. Acervuli and setae on the stromatic structure ere formed at 96 hours. The infected seed coat was not only severely collapsed, but also infection hyphae were observed on the disintegrated seed coat, resulting severe plasmolysis of nucellus and embryo.

• Korean Journal Plant Pathology
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• v.13 no.1
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• pp.22-29
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• 1997

Etiological and ecopathological studi88888es on the leaf blight of kiwifruit (Chinese gooseberry), a disease newly found in 1993 in Korea, were carried out in this experiment. The leaf blight symptom was prevalent in the southern area of Chonnam Province where kiwifruits were widely cultivated. The disease occurred from July to fall, causing early defoliation of kiwifruit vines. Small brownish circular or irregular lesions appeared initially on the leaves, starting from the marginal leaf areas, and enlarged. Afterwards small grayish black granules (acervuli) were formed on the lesions. The color of old lesions changed to grayish brown or grayish white. The causal fungus was identified as Pestalotiopsis menezesiana (Bress. & Torr.) Bissett according to its morphological characters and pathogenicity (pathogenic to Chinese gooseberry and grapevine, but not to other hosts of Pestalotiopsis spp.such as tea, apple, persimmon, and chestnut). As P. longiseta and P. neglecta were reported recently in Japan as pathogens causing similar blight symptoms in kiwifruit, P. menezesiana is a new leaf blight pathogen in kiwifruit. Development of the disease was stimulated by wounding, prevailing wind, and drought. The causal fungus was proven to be overwintered in the diseased leaves on the ground surface.

• Research in Plant Disease
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• v.17 no.2
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• pp.228-231
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• 2011

Since 2008, a new leaf spot disease has been found in loquat tree (Eriobotrya japonica) at a nursery station in Goheung, Korea. Above 50% of the seedlings developed the spot symptoms on the leaves. The infected plants were generally reduced in the seedling vigour and early defoliation was occurred. The infected leaves developed grayish lesion with dark reddish brown margin. The pathogen developed round to ellipsoidal acervuli on the lesion. Based on morphological characteristics of the pathogen, the fungus was identified as Entomosporium mespili. The cultured pathogen successfully reproduced the same disease symptom on the leaves of loquat tree and found to be E. mespili. A monoconidial culture was deposited in Korean Agricultural Culture Collection (KACC 44727). This is the first report of E. mespili causing leaf spot of loquat tree in Korea.

• Korean Journal Plant Pathology
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• v.2 no.1
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• pp.31-36
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• 1986

The symptom of anthracnose of chinese matrimony vine (Lycium chinense Mill) was darkbrown to black, water­soaked lesions with acervuli on fruits. Field survey revealed that the incidence rate of anthracnose ranged from $0.8\%\;to\;23\%$. to Colletotrichum gloeosporioides Penz and C. dematium(Fr.) Grove were identified as the causal organisms of the disease. C. gloeosporioides and C. dematium produced severe symptoms on fruits resulting in complete necrosis, but produced no or mild symptoms on leaves and stems of chinese matrimony vine. Of three isolates of C. dematium, isolate I and isolate III caused severe infection on immature fruits and isolate I was the most pathogenic on mature fruits of the plant. Isolates II of C. dematium caused relatively severe lesions on pepper fruit, but C. gloeosporioides was pathogenic on apple fruit.

• Korean Journal Plant Pathology
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• v.13 no.4
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• pp.195-199
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• 1997

Anthracnose symptoms were observed on the commercially cultivating ultivating cyclamen in Chonbuk province in 1995. The symptoms of infected flowers were small, circular and dark brown ring-spots or water-soaked lesions and gradually changed to lack blight. Mycelial colony of the isolates was light or whitish gray to dark gray on potato dextrose agar. Conidia were straight cylindrical and obtuse at the apex and measured 8.3~15.0${\times}$2.5~6.3 ${\mu}m$ in size. Appressoria were brown to dark brown and clavate, but most of them were irregular. Acervuli on lesions were brown, rounded and measured 50~140${\times}$32.5~90 ${\mu}m$ in size. The optimum temperatures for mycelial growth and conidial sporulation were ranged from 25 to 30$^{\circ}C$. Thus, based on mycological characteristics of the fungus, the causal agent of cyclamen anthracnose was identified as Colletotrichum gloeosporioides Penz.

• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.36-36
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• 2014

Apple blotch, caused by Marssonina coronaria, induce early defoliation in apple and leading to critical economic losses in apple orchards in Korea. Since M. coronaria is difficult to culture, we developed isolation and cultural method. We collected M. coronaria isolates from Gyeongbuk Province and then constructed phylogentic tree based on ITS regions. As the results, phylogenetic relationship indicated that all Korean isolates formed a same cluster and closely related to Chinese isolates [1]. Ecological characteristic of M. coronaria have been observed in apple orchards which located in Gyeongbuk Province from 2011 to present. As the results, the typical apple blotch symptoms were observed from July, and then the infected leaves were discolored and formed acervuli on the leaves. After rainfall, severe infection of symptoms such as discoloration and early defoliation were continuously observed until October. Also overwintered conidia were observed in next March on the fallen diseased leaves [2]. In the last 5 years, ascopores of M. coronaria were not observed in apple orchards which were severely infected by M. coronaria in Korea. Thus, it is assumed that overwintered conidia could be a primary inoculum of M. coronaria. Meanwhile, apple blotch has long latent periods compare to other apple disease. During the latent period, early diagnosis of apple blotch is the most important to control the disease by spray fungicide. In this reason, we developed novel diagnostic method to detect M. coronaria during latent period using optical coherence tomography (OCT) and Loop-mediated isothermal amplification (LAMP) method [2, 3]. In this presentation, it will introduce ecological characterization of M. coronaria in Korea and unique detection technique of M. coronaria in apple. It will be helpful to develop new strategies to control apple blotch in Korea.

• Korean Journal Plant Pathology
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• v.2 no.2
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• pp.107-113
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• 1986

Each of 48 monoconidial isolates of Colletotrichum gloeosporioides Penz. obtained from diseased fruits of pepper was classified into strain G or strain R based upon pathogenicity to green and red fruits, morphology of conidia, and cultural characteristics in potato dextrose agar. The strain G was designated for isolates to cause anthracnose symptoms both on green and red fruits. All isolates of the strain G produced conidia abundantly. but produced no perithecia and setae in PDA. Conidia of all isolates in the strain G were attenuated or round at one end. The optimum temperature for mycelial growth of strain G was $26-28^{\circ}C$. The mycelia of strain G in PDA appeared to be whitish when young, and turned to be dark in old culture. Symptoms on pepper fruits caused by the strain G were somewhat sunken to be circular to elliptical lesions. Yellowish conidial masse were observed at the center of lesions, and the lesions turned to irregular shape and to reddish brown color in the later stage of disease development. No setae were visible on the acervuli. The strain R was designated for isolates to cause anthracnose symptoms only on red fruits of pepper. All isolates of the strain R produce conidia, and perithecia of Glomerella cingulata (Stonem.) Spauld. & v. Sch. in PDA. Some isolates of the strain R produced setae in culture under fluorescent light. Conidia of all isolates in the strain R were round and blunt at the ends. The optimum temperature for mycelial growth of strain R was the same as that of strain G. The mycelial growth of strain R was faster than that of strain G in PDA. The mycelia of strain R in PDA appeared to be gray to dark. Symptoms on pepper fruits caused by the strain R were circular to irregular black ring-spots Short setae or no setae were visible on the acervuli.

• Research in Plant Disease
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• v.8 no.3
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• pp.175-178
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• 2002

Two novel casual agents of soybean sprout rot occurred at soybean sprouts cultivated under structure in Suwon area in 1997 were isolated and their pathogenicity was tested in vivo. An isolate formed crowed, black acervuli which were oval to elongated with numerous black, needlelike, intermixed long and short setae, 65~110$\times$3.5~6.6 ${\mu}{\textrm}{m}$. Conidia were curved, lunate, unicellular and hyliane and measured 21.5~22.5$\times$3.5~4.0 ${\mu}{\textrm}{m}$. The other isolate produced conidia with straight and cylindrical, and measured 14.0~17.5$\times$3.5~4.5 ${\mu}{\textrm}{m}$. Apressorium size was measured 6.3~8.5$\times$4.5~5.0 ${\mu}{\textrm}{m}$. The agents were identified as Colletotrichum truncatum and C. gloeosporioides based on their morphological characteristics. There was a large difference in pathogenicity between two isolates. C. gloeosporioides caused dark brownish discoloration of whole plants. It showed high pathogenicity with severe disease development. Meanwhile C. gloeosporiodes caused light brown spots on cotyledon and its pathogenicity was not strong. The soybean sprout rot occurred by the two Colletotrichum species was firstly reported in soy-bean sprout in Korea, and we suggest it as “Colletotrichum rot of soybean sprout”.

• The Korean Journal of Mycology
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• v.16 no.3
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• pp.151-156
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• 1988

A leaf anthracnose disease of pepper(Capsicum annuum L.) seedling caused by Colletotrichum coccodes was found in fields of Chungnam District for the first time in 1988. Initial symptom of the disease was spotting on leaves and stems of the seedlings. The spots became sunken and gradually increased in size and coalesced to form bigger irregular spots and blights on the leaves. In severely affected fields, many pepper seedlings were defoliated and lodged. Field survey revealed that the infection rate of anthracnose ranged form 15.3% to 92.3%. Conidia from lesions on seedlings were hyaline, aseptate, straight, cylindrical with obtuse ends, $115-25(av.\;19.\;5){\times}2.5-4.8{\mu}m(av.\;3.3{\mu}m)$ and setaes were straightly extended above the acervuli, $41.3-136.3\;{\um}m(av.\;85.0{\mu}m)$ long. The fungus produced abundant sclerotia on PDA when it was cultured under darkness. In the inoculation experiments, the fungus was found to infect pepper seedlings and fruits, and fruits of tomato and egg plant.