• Mycobiology
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• v.40 no.3
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• pp.214-216
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• 2012

Soft rot on banana fruit caused by Rhizopus oryzae was identified for the first time in Korea. Colonies were white to light brown and formed numerous sporangiospores. Optimum temperature for mycelial growth was $30^{\circ}C$. Sporangia were globose and $30{\sim}200{\mu}m$. Sporangiophores were usually straight, $8{\sim}20{\mu}m$, and rhizoids usually in groups of 3~5. Columella were globose to sub-globose and $90{\sim}110{\mu}m$. Sporangiospores were sub-globose or oval and $4{\sim}10{\mu}m$. Based on its mycological characteristics, molecular analysis, and pathogenicity to host plants, this fungus was identified as Rhizopus oryzae Went & Prisen Geerligs. This is the first report of soft rot on banana caused by Rhizopus oryzae in Korea.

• The Korean Journal of Mycology
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• v.30 no.2
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• pp.166-169
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• 2002

A fruits soft rot caused by Rhizopus stolonifer found on citrus fruit in Jinjn City Agricultural Products Wholesale Market. The disease infection usually started from wounding. At first, the lesions started water soaked and rapidly softened and diseased lesion gradually expanded to other fruits in the same container. The mycelia grew vigorously on the surface of fruits and formed sporangia, sporangiophores and stolons. Sporangiophores were $900{\sim}4300{\mu}m$ in size. Sporangia were globose or subglobose and $98{\times}346{\mu}m$ in size. The color of sporangia was white at first and then turned black with many spores. Columella were globose or ellipsoid and $60{\sim}216{\times}72{\sim}143{\mu}m$ in size. Sporangiospores were globose or ellipsoid, brownish-black streaked and $8{\sim}18.3{\mu}m$ in diameter. Zygospores were globose, black and $98{\sim}176{\mu}m$ in size. The optimum temperature for mycelial growth of the fungus on PDA was $25^{\circ}C$. The causal fungus was identified as Rhizopus stolonifer. This is the first report of rhizopus soft rot on citrus fruit caused by R. stolonifer in Korea.

• Research in Plant Disease
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• v.17 no.3
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• pp.396-398
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• 2011

Soft rot disease on Raspberry (Rubus crataegifolius Bunge) was observed in sale boxes at Jinju City Wholesale Market of Agricultural Products in June 2010. The infected fruits were rapidly water-soaked, softened, black and eventually rotted. The colonies on the infected fruits were white to light brown, formed numerous sporangiospores. Optimum temperature for the mycelial growth of the causal fungus on PDA was $30^{\circ}C$ and growth was still apparent at $37^{\circ}C$. Sporangia were globose, white at early and gradually to black, and 40-210 ${\mu}m$ in diameter. Sporangiophores were white to mid brown as maturation and 8-20 ${\mu}m$ in diameter. Columella were globose to sub-globose, and the size of the diameter was 85-120 ${\mu}m$ in diameter. Sporangiospores were sub-globose, rhomboidal and irregular, streaked and 5-10 ${\mu}m$ in length. On the basis of symptom, mycological characteristics, ITS rDNA sequence analysis, and pathogenicity of the fungus, the causal fungus was clearly identified as Rhizopus oryzae Went & Prinsen Geerligs. This is the first report of soft rot by R. oryzae on R. crataegifolius in Korea.

• Research in Plant Disease
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• v.17 no.1
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• pp.78-81
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• 2011

Soft rot caused by Rhizopus oryzae occurred on unshiu orange (Citrus unshiu Marc.) sampled from commercial markets in Jinju, Korea, 2010. The first symptom of soft rot on orange is a water-soaked appearance of the affected tissue. The infected parts later disintegrated into a mushy mass of disorganized cells followed by rapid softening of the diseased tissue. The lesion on orange was rapidly softened and rotted, then became brown or dark brown. Optimum temperature for mycelial growth of the causal fungus on potato dextrose agar was $30^{\circ}C$ and growth was still apparent at $37^{\circ}C$. Sporangiophores were $6{\sim}20\;{\mu}m$ in diameter. Sporangia were globose and $40{\sim}200\;{\mu}m$ in size. The color of sporangia was brownish-grey to blackish-grey at maturity. Sporangiospores were sub-globose, brownish- black streaked and $4{\sim}10\;{\mu}m$ in size. Columella were globose to sub-globose and $85{\sim}120\;{\mu}m$ in size. On the basis of mycological characteristics, pathogenicity test, and the ITS sequence analysis, the causal fungus was identified as Rhizopus oryzae. To our knowledge, this is the first report of soft rot caused by R. oryzae on unshiu orange in Korea.

• The Korean Journal of Mycology
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• v.40 no.1
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• pp.65-68
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• 2012

In July and August 2011, a disease suspected to be Rhizopus soft rot was observed on peach (Prunus persica var. vulgaris) at the Wholesale Market for Agricultural Products, Jinju, Korea. The first symptom of soft rot on peach is a water-soaked appearance of the affected tissue. The infected parts later disintegrated into a mushy mass of disorganized cells followed by rapid softening of the diseased tissue. The lesion on peach was rapidly softened and rotted, then became brown or dark brown. Optimum temperature for mycelial growth of the causal fungus on PDA was $30^{\circ}C$and growth was still apparent at $37^{\circ}C$Sporangiophores were 6~20 ${\mu}m$ in diameter. Sporangia were globose and 35~200 ${\mu}m$ in size. The color of sporangia was brownish-grey to blackish-grey at maturity. Sporangiospores were sub-globose, brownish- black streaked and 5~10 ${\mu}m$ in size. Columella were globose to sub-globose and 85~120 ${\mu}m$ in size. On the basis of mycological characteristics, pathogenicity test, and molecular identification, the causal fungus was identified as Rhizopus oryzae Went & Prinsen Geerligs. To our knowledge, this is the first report of soft rot caused by R. oryzae on peach in Korea.

• Korean Journal Plant Pathology
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• v.10 no.3
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• pp.175-180
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• 1994

The fungal pathogen Monosporascus annonballus was first isolated in Korea from the rotted roots of bottle gourd stocks of collapsed watermelon plants in fields near Chochiwon, Choongnam province in July, 1993. Perithecia of M. cannonballus were dark brown to black, globose, 220~570 ${\mu}{\textrm}{m}$ in diam. and had many asci. Asci are hyaline, clavate to pyriform, and 50~120$\times$35~570 ${\mu}{\textrm}{m}$ in size. Ascospores were aseptate, dark brown to black, globose, 25~45$\times$30~50 ${\mu}{\textrm}{m}$ in diam, and borne singly in each ascus. The fungus grew in the temperature range of 4 to 34$^{\circ}C$, best at 3$0^{\circ}C$. The optimum pH for growth was 6.8. Mycelial growth rate of M. cannonballus was 25.5mm/day on PDA at 26$^{\circ}C$. Perithecia began to form after 20-day-growth on PDA and produced mature asci after 30 days or later. In the greenhouse inoculation tests, the fungus developed water-soaked lesions on roots of bottle gourd seedlings and was then reisolated from the lesions. Severed damages on watermelon plants by M. cannonballus are greatly concerned in Korea, since no stocks used for watermelon cultivation have reported to be resistant to the fungus.

• The Plant Pathology Journal
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• v.22 no.3
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• pp.211-214
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• 2006

In 2004 and 2005, Phytophthora rot on Luffa cylindrica which had not been reported in Korea occurred in the experimental field at Gyeongsangnam-do Agricultural Research and Extension Services. The disease initiated on leaves and fruits of the plant with small watersoaked dark brown spots and progressed rapidly. The causal pathogen isolated from diseased tissues was identified as a Phytophthora sp. because of aseptate mycelia and zoospores released directly from sporangia. The fungus grew well on PDA and 10% V-8 juice agar showing an arachnoid or rosaceous colony pattern. Sporangia formed abundantly in water and were conspicuously papillate, noncaducous, ovoid to globose, and sized $26\sim62\times19\sim38{\mu}m$. The fungus was heterothallic as producing sexual reproduction structures only when mated with only A2 standard mating type strain. Oogonia and oospores were spherical, smooth walled, and measured as $20\sim28{\mu}m\;and\;16\sim24{\mu}m$, respectively. Oospores were aplerotic and antheridia were amphigynous, unicellula and spherical. Chlamydospores were globose and $20\sim38{\mu}m$ in diameter. Optimum temperature for growth was around $28\sim30^{\circ}C$. The fungus caused similar symptoms on artificially inoculated plant and could be re-isolated thereby proving Koch's postulation. Based on the mycological criteria investigated in this study, the causal fungus of Luffa sylindrica rot was identified as Phytophthora nicotianae. This is the first report of Phytophthora rot of Luffa cylindrica caused by P. nicotianae in Korea.

• Mycobiology
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• v.34 no.3
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• pp.151-153
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• 2006

Rhizopus soft rot caused by Rhizopus stolonifer occurred on pears (Pyrus serotina) in the Jinju City Agricultural Products Wholesale Market in Korea from 2004 to 2005. The infection usually started from wounds due to cracking at harvest time. The lesions started as water-soaked, rapidly softened, then gradually expanded. The mycelia grew vigorously on the surface of the fruits and formed stolons. Colonies on potato dextrose agar at $25^{\circ}C$ were white cottony to brownish black. Sporangia were globose, black and $90{\sim}120\;{\mu}m$ in size. Sporangiophores were light brown and $480{\sim}2600{\times}12{\sim}18\;{mu}m$ in size. Sporangiospores were globose to oval, brownish, streaked, and $8{\sim}14{\times}6{\sim}10\;{\mu}m$ in size. Columella were light brownish gray, hemispherical and $70{\sim}80\;{\mu}m$ in size. On the basis of these symptoms, mycological characteristics and pathogenicity tests on host plants, the fungus was identified as Rhizopus stolonifer (Ehrenb.) Vuill. This is the first report of rhizopus soft rot on pear (P. serotina) caused by R. stolonifer in Korea.

• The Plant Pathology Journal
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• v.23 no.1
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• pp.31-33
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• 2007

Phytophthora rot on broad bean(Vicia faba) occurred in the experimental field at Gyeongsangnam-do Agricultural Research and Extension Services from 2004 to 2006. The fungus isolated from the diseased plants grew well on potato dextrose agar and showed an arachnoid or rosaceous colony pattern. Sporangia were conspicuously papillated, noncaducous, ovoid to globose, and $25-64{\times}18-44{\mu}m$ in size. Oogonia and oospores were spherical and measured as 20-32 ${\mu}m$ and 16-28 ${\mu}m$ in size, respectively. Oospores were relatively small and aplerotic. Antheridia were amphigynous, spherical, and unicellula. Chlamydospores were globose and 18-40 ${\mu}m$ in size. Optimum temperature for growth was about $28^{\circ}C$ on potato dextrose agar. The disease occurred in all parts of the plant including roots, stems, leaves and pods in the field. The symptoms similar to those of naturally infected plants were induced by artificial inoculation and the pathogen was re-isolated from the plant. On the basis of mycological and pathological characteristics, the causal pathogen of broad bean rot was identified as Phytophthora nicotianae. This is the first report of Phytophthora rot of broad bean caused by P. nicotianae in Korea.

• Research in Plant Disease
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• v.20 no.1
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• pp.50-53
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• 2014

Rhizopus soft rot of lily (Lilium longiflorum) caused by Rhizopus oryzae was observed in the experimental field in Taean Lily Experiment Station in Korea, 2012. The typical symptoms were water-soaked lesions on bottom stem and leaf rot. The lesion rapidly expanded and the plant was softened totally. The fungus grew vigorously at an optimum temperature ($25^{\circ}C$) and brownish colony and black sporangia were formed on potato dextrose agar medium. Sporangiophores formed on end of sporangia were sub-globose, brownish and $6-10{\mu}m$ in size. Sporangia were globose, blackish and $87-116{\mu}m$ in size. Sporangiospores were irregularly oval and sub-globose, brownish $4-8{\mu}m$ in size. On the basis of mycological characteristics, analyzing sequences of internal transcribed spacer region of ribosomal DNA, and pathogenicity test on host plants, the causal fungus was identified as R. oryzae. This is the first report of Rhizopus soft rot on lily caused by R. oryzae in Korea.