• The Plant Pathology Journal
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• v.23 no.1
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• pp.7-12
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• 2007

Perilla rust is a damaging disease in perilla cultivation in Korea. Its causal agent was identified as Coleosporium plectranthi based on descriptions of morphological characteristics of spores and spore-producing fruiting structures(in uredinial and telial stages from perilla and in aecial stage from the alternate host pine) collected in 15 locations in Korea during the disease survey from 2004 to 2006. These characteristics were yellow or orange uredinium; globose or ellipsoid urediniospore of $20.8{\mu}m{\times}18{\mu}m$ in size; verruca of $0.3mm{\times}1.2mm$; orange telium; one-celled, oblong ellipsoid teliospore of $63.1{\mu}m{\times}19.7{\mu}m$ with one-layered crusts or four-celled(when mature), internal basidium of $64.2{\mu}m{\times}19.7{\mu}m$; ellipsoid to globoid basidiospore of $20.3{\mu}m{\times}12{\mu}m$; type 2 spermogonium; yellow, broadly ellipsoid peridial cell of $35.6{\mu}m{\times}23.1{\mu}m$; and broadly ellipsoidal or subglobose aeciospore of $25.9{\mu}m{\times}18.8{\mu}m$. Phylogenetic analysis of 28S rDNA sequences revealed the closest relatedness to those of the genus Coleosporium, a monophyletic group distinguished from other rust fungi and divided into two main lineages, one of which was C. plectranthi grouped with high bootstrap value(96%). In pathogenicity test, both aeciospores and urediniospores caused rust development on perilla leaves. This is the first description of C. plectranthi causing perilla rust with the first findings of its telial stage on perilla and the first rust disease on the aecial host in Pinus densiflora. These aspects would provide basic information for the development of control measures of the disease.

• Research in Plant Disease
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• v.8 no.4
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• pp.224-227
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• 2002

From the necrotic stem of aquaculture Dracaena for living room decoration, we observed conidia on acervuli with occasional setae and perithecia in vivo. Morphological characters were; acervuli, dark brown and 300-500 ${\mu}{\textrm}{m}$ in diameter; conidia, hyaline, aseptate, cylindrical to slightly ellipsoid with rounded apex and narrow truncate base on phialidic conidiophores, 12.5-17.5 ${\mu}{\textrm}{m}$; setae, variable in length 1-4 septate, slightly swollen at the base and tapered to the apex, 200 ${\mu}{\textrm}{m}$; appressoria, dark brown ovate to obovate irregular 5-12.5 ${\mu}{\textrm}{m}$, perithecia on decayed stem, globose, dark brown and black 85-300 ${\mu}{\textrm}{m}$; asci 8 spored, clavate to cylindrical; 50-62.5$\times$8-10 ${\mu}{\textrm}{m}$; ascospores, oval to fusiform, sometimes slightly curved, aseptate, hyaline. Above characteristics were also confirmed in vitro. Colletotrichum state of this fungus was also compared with C. lindemuthianum and C. musae in terms of morphology of conidia and setae and growth on PDA etc. This fungus was identified as Glomerella cingulata(Stonem.) Spaulding & Schrenk(Colletotrichum gloeosporioides(Penz. Sacc.).

• Research in Plant Disease
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• v.10 no.2
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• pp.100-104
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• 2004

Two species of Phytophthora were isolated from a leaf blight disease found on castor bean plants growing at a residential area of Hwanggeum-dong in Daegu city. One species was producing conspicuously papillate, noncaducous, ovoid to obpyriform sporangia, 31.2-58.5 ${\times}$ 25.4-44.1 ${\mu}{\textrm}{m}$ in range with an average of 46.4 $\pm$ 6.5 ${\times}$ 35.9 $\pm$ 4.7 ${\mu}{\textrm}{m}$ on simple sympodial sporangiophores, was heterothallic with oogonia globose, 22.5-35.0 ${\mu}{\textrm}{m}$ with an average of 30 $\pm$ 3.3 ${\mu}{\textrm}{m}$ in diameter, oospores plerotic, 18.8-30.0 ${\mu}{\textrm}{m}$ in range averaging 25.4 $\pm$ 2.8 ${\mu}{\textrm}{m}$, and with antheridia amphigynous. This species was identified as P. nicotianae Breda de Haan. The other species produced papillate, caducous, ovoid to ellipsoid sporangia with pedicel, 21.5-54.6 ${\times}$ 17.6-34.3 ${\mu}{\textrm}{m}$ in range with an average of 41.7 $\pm$ 7.1 ${\times}$ 28.4 $\pm$ 4.0 ${\mu}{\textrm}{m}$, and was heterothallic with oogonia globose, 21.3-26.8 ${\mu}{\textrm}{m}$ with an average of 23.0 $\pm$ 1.6 ${\mu}{\textrm}{m}$ in diameter, oospores plerotic, 17.5-23.8 ${\mu}{\textrm}{m}$ in range averaging 20.2 $\pm$ 1.8 ${\mu}{\textrm}{m}$, and with antheridia amphigynous. This species was identified as P. palmivora (Butler) Butler. Both species produced chlamydospores. Pathogenicity of the 2 speices was confirmed by foliar inoculation of castor bean seedlings. Both species have been reported to infect castor bean plants in a few foreign countries but it is the first that a disease of castor bean plants caused by either or both of the species was found in Korea.

• The Plant Pathology Journal
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• v.21 no.3
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• pp.293-296
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• 2005

A leaf blight caused by a species of Phytophthora was found on fatsia plants (Fatsia japonica Decne et Planch.) growing in an apartment garden in Daegu, Korea in late April to May, 2003. The species of Phytophthora isolated from the diseased plants produced sporangia and sex organs on V8 juice agar medium. Sporangia were papillate, ovoid to subspherical, and caducous with a pedicel. The dimensions of the sporangia were $31.2-46.8\times23.4-33.2{\mu}m$ in range, $39.6\pm4.1\times28.3\pm2.8{\mu}m$ in $average{\pm}standard$ deviation, I/b ratio approximately 1.40, with papillae about $3.6{\mu}m$ high, and pedicels $0.9­5.8{\mu}m$ long. Oogonia were spherical, $25.0-32.5{\mu}m$ in range with an average of $28.2\pm2.3{\mu}m$ in diameter. Antheridia were predominantly paragynous, globose to ovoid, $8.8-13.8\times7.5-10.0{\mu}m$ with an average of $10.9\pm1.2 \times9.2\pm1.1{\mu}m$. Oospores in the oogonia were aplerotic or plerotic, and $20.0-25.0{\mu}m$ in diameter with an average of $23.5\pm1.5{\mu}m$. Pathogenicity of the isolate was confirmed on detached leaves of fatsia. The disease was observed only in April and May of 2003 when the weather was unusually wet. It then diminished with increase of temperature in the year and did not appear again on the same plants in 2004. Thus, the fungus appeared to be a relatively weak pathogen of fatsia.

• Research in Plant Disease
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• v.11 no.2
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• pp.204-207
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• 2005

A Rhizopus soft rot caused by Rhizopus stolonifer occurred on Momordica charantia at Daesan-myon, Chang-won city, Gyeongnam province from 2003 to 2005. The disease usually started from wound on fruit with water-soaking lesions. The lesion rapidly expanded and softened. The fungal mycelia grew vigorously and sporangia, sporangiophores, and stolons were formed on surface of the fruit. Spoyangiophores were $15\~30{\mu}m$ in width. Sporangia were globose or hemispheric and $90\~180{\mu}m$ in size. The color of sporangia was white and cottony at first and turned to brownish black with many spores at maturity. Columella were hemispheric and $80\~150{\mu}m$ in size. Sporangiospores were irregular round or oval, brownish-black streaked and $7\~18{\times}6\~12{\mu}m$ in size. The optimum temperature for mycelial growth of the fungus on PDA was $25^{\circ}C$. On the basis of mycological characteristics and pathogenicity to host plants, the causal fungus was identified as Rhizopus stolonifer (Ehrenberg ex. Fr,) Lind. This is the first report of Rhizopus soft rot on M. charantia caused by R. stolonifer in Korea.

• Journal of Korean Society of Forest Science
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• v.96 no.5
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• pp.515-519
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• 2007

An imperfect fungus Fusiococcum species was isolated from Quercus dentata. A naturally infected Daimyo oak tree was collected and showed elongate wounds on the stem. The fungal cultures were initially white and cottony, and later turned dark gray. Numerous solitary pycnidia were developed on the medium surface, and typically spherical. Yellowish conidial masses were exuded from pycnidia on the culture plates. Conidial masses were swollen and measured as approximately 100 to $300{\mu}m$ in length. It appeared that conidia were usually held together in globose to oval drops. Conidia were hyaline, single-celled (nonseptate), ellipsoid to fusoid, and measured as approximately $8.0{\times}2.7{\mu}m$. Based on these cultural and morphological characteristics, the fungal isolate was identified as a species of Fusicoccum Corda. To preserve and examine fungal spores exuded from pycnidia on the medium surface, a vapor fixation procedure for scanning electron microscopy was employed in this study. The specimens were exposed to the vapor of 2% (v/v) glutaraldehyde and 2% (w/v) osmium tetroxide each for 2 h. With the vapor fixation we obtained excellent retention of conidial masses in this study. The simple and versatile procedure for demonstrating fungal spores and their exudation from fruiting bodies would facilitate characterization of diverse pathological and environmental isolates as they are in native environments.

• The Plant Pathology Journal
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• v.18 no.3
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• pp.161-164
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• 2002

Colletotrichum musae was isolated from dark-brown anthracnose lesions on commercial banana (Musa sapientum L.) to establish the causal agent of the symptom. The fungus grew fast and produced white aerial mycelium on PDA. Acervuli developed abundantly on culture plates after incubation for 10 days at $25^{\circ}C$. Pinkish conidial masses were produced on the acervuli, which mostly coalesced together, Conidia were aseptate, hyaline, straight, ellipsoid to globose, and 14.5$\times$6.9 $\mu\textrm{m}$ in size. Black, clavate, round, or irregular-shaped appressoria measuring 8.8$\times$6.8 $\mu\textrm{m}$ were readily formed from germ tubes. Setae-like structures were not found either on the lesion or on the cultures. Sclerotia were also absent. Among the media, PDA medium was the best for mycelial growth. The optimum temperature for mycelial growth was $28^{\circ}C$, while the optimum pH ranged from pH 5.5 to 6.5. The isolates of C musae caused black necrotic lesions on banana fruits by needle-wound inoculation, and orange-colored spore masses were produced on the lesions. The fungus also caused discoloration on apple fruits inoculated.

• Research in Plant Disease
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• v.14 no.2
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• pp.127-130
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• 2008

Rhizopus soft rot caused by Rhizopus stolonifer on June, 2008 occurred on Rubus crataegifolius Bunge in the box at Jinju City Wholesale Market of Agricultural Products at Gyeongnam province in Korea. The infected fruits were rapidly water-soaked, softened, black and eventually rotted. The symptoms occurred after infecting wounds at harvest time. The colony were white to light brown, formed much sporangiospores. The optimum temperature of the fungus on potato dextrose agar was $30^{\circ}C$. Sporangiophores were $12{\sim}25{\mu}m$ in width. Sporangia were globose or hemispheric, white at first and gradually to black, and $82{\sim}195{\mu}m$ in size. Columella were hemispheric, and $70{\sim}92{\mu}m$ in size. Sporangiospores were irregular round or oval, brownishblack and $9{\sim}21{\times}7{\sim}8{\mu}m$ in size. On the basis of symptom, mycological characteristics and pathogenicity of the fungus, the causal fungus was identified as Rhizopus stolonifer. This is the first report of Rhizopus soft rot by R. stolonifer on R. crataegifolius in Korea.

• The Korean Journal of Mycology
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• v.35 no.1
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• pp.54-57
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• 2007

Rhizopus soft rot caused by Rhizopus stolonifer occurred on banana (Musa sapientum) in the box at Jinju City Wholesale Market of Agricultural Products at Gyeongnam province in Korea. The infected fruits were rapidly water-soaked, softened, blackened and eventually rotted. They were infected from wounds at harvest time. The colony of the isolate from the infected fruit was white to light brown and formed many sporangiospores. The optimum growth temperature of the fungus on potato dextrose agar was $30^{\circ}C$. Sporangiophores were $12{\sim}26\;{\mu}m$ in width. Sporangia were globose or hemispheric, white at first and changed gradually to black, and $83{\sim}195\;{\mu}m$ in size. Columella were hemispheric, and $72{\sim}125\;{\mu}m$ in size. Sporangiospores were irregular round or oval, brownish-black and $9{\sim}20{\times}7{\sim}8\;{\mu}m$ in size. On the basis of symptom, mycological characteristics and pathogenicity to banana, the causal fungus was identified as Rhizopus stolonifer. This is the first report of Rhizopus soft rot by R. stolonifer on banana in Korea.

• The Korean Journal of Mycology
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• v.36 no.2
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• pp.199-202
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• 2008

Rhizopus soft rot caused by Rhizopus stolonifer occurred on melon (Cucumis melo L.) in the box at Jinju City Wholesale Market of Agricultural Products at Gyeongnam province in Korea. The infected fruits were rapidly water-soaked, softened, black and eventually rotted. The symptoms were infected from wounds at harvest time. The colony were white to light brown, formed much sporangiospores. The optimum temperature of the fungus was $30^{\circ}C$. Sporangia were globose or hemispheric, white at first and gradually to black, and $80{\sim}195\;{\mu}m$ in size. Sporangiophores were $12{\sim}24\;{\mu}m$ in width. Columella were hemispheric, and $70{\sim}90\;{\mu}m$ in size. Sporangiospores were irregular round or oval, brownish-black and $9{\sim}20\;{\times}\;6{\sim}8\;{\mu}m$ in size. On the basis of symptom, mycological characteristics and pathogenicity to melon, the causal fungus was identified as Rhizopus stolonifer (Ehrenb.) Vuill.. This is the first report of Rhizopus soft rot by R. stolonifer on melon in Korea.