• Research in Plant Disease
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• v.7 no.2
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• pp.112-115
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• 2001

Blossom blight of petunia caused by Choanephora cucurbitarum was found in greenhouses around Jinju area, Gyeongnam province, Korea in April 2001. The disease started with water-soaked lesions on the flower which rapidly withered and was rotten. Calyces developed water-soaked, dark-green lesions, and then were rotten. Whitish mycelia and monosporous sporangiola were produced on the lesions. The fungus isolated from the lesions produced white to pale yellowish brown mycelia with scattered monosporous sporangiola on potato-dextrose agar (PDA) plates. Size of sporangium was 37.2~135.8 um. Monosporous sporangiola were elliptic, fusiform or ovoid, and brown in color and their size was 10.4~22.4$\times$7.4~12.9 um. Sporangiospores were elliptic, fusiform or ovoid in shape, dark brown or brown in color and were 13.7~23.5$\times$8.7~13.8 um in size, and had appendaged appressorium of 3 or more. Zygospores were black, and 40.8~61.5 um in size. The fungus grew on PDA at 15-4$0^{\circ}C$, and optimum temperature was 3$0^{\circ}C$. This is the first report on the blossom blight of petunia caused by C. cucurbitarum in Korea.

• Mycobiology
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• v.33 no.3
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• pp.163-165
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• 2005

In April 2002 and 2003, soft rot on fruit of eggplant (Solanum melongena) caused by Choanephora cucurbitarum was observed in the experimental fields at Gyeongnam Agricultural Research and Extension Services in Korea. The disease began with water-soaking and dark-green lesions, and then the infected tissues were rapidly rotten. Sporangium was subglobose in shape and sized $40{\sim}130\;{\mu}m$. Monosporous sporangiola were elliptic, fusiform or ovoid, brown in color, and measured as $12{\sim}20\;{\times}\;6{\sim}14\;{\mu}m$. Sporangiospores having three or more appendages were elliptic, fusiform or ovoid in shape, dark brown or brown in color, and sized $14{\sim}20\;{\times}7{\sim}16\;{\mu}m$. The fungus grew well on potato dextrose agar between 15 and $40^{\circ}C$ and its optimum growth temperature was $30^{\circ}C$. Based on morphological characteristics, the causal fungus of the fruit soft rot of eggplant was identified as C. cucurbitarum. This is the first report on the soft rot of S. melongena caused by C. cucurbitarum in Korea.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.354-356
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• 2001

In August 2001, pod rot of cowpea caused by Choanephora cucurbitarum was found in the experimental fields of the Gyeongsangnam-do Agricultural Research and Extension Services, Korea. Initial symptoms of the disease were the appearance of water-soaked, dark-green lesions and followed by rapid rotting of the infected tissues. As the disease progressed, whitish mycelia and monosporous sporangiophore with monosporous sporangiola were produced on the lesions. The fungus produced white to pale yellowish brown mycelia with scattered monosporous sporangiophore and monosporous sporangia containing sporangiospores on potato dextrose agar (PDA). Monosporous sporangiophore was long, slender and branched at the apex, with each branch bearing a sporangiospore. Sporangium was subglobose in shape and 42.6-112.6 ㎛ in size. Monosporous sporangiola were elliptic, fusiform or ovoid, brown in color, and 9.8-23.4$\times$7.2-12.8 ㎛ in size. Sporangiospores were elliptic, fusiform or ovoid in shape, dark brown or brown in color, 12.9-24.6$\times$8.6-15.4 ㎛ in size, and had three or more appendages. Zygospores were black and 43.6-72.4 ㎛ in size. The fungus grew on PDA at 15-40$\^{C}$, and optimum temperature was 30$\^{C}$. This is the first report on pod rot of cowpea caused by C. cucurbitarum in Korea.

• Research in Plant Disease
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• v.8 no.1
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• pp.55-58
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• 2002

In July 2001, rotting and shivering flowers of cotton rose (Hibiscus mutabitis) were fecund in the flower beds along the roadsides in Jinju area. The disease first started as water-soaking, dark-green lesions on the petals, and then whole flower was rotted rapidly, Whitish mycelia and monosporous sporangiophore with monosporous sporangiola were formed abundantly on the lesions. Colony appeared as white to pale yellowish brown mycelia on potato dextrose agar medium (PDA). Monosporous sporangiophore was long slender and branched at the apex, each branch bearing a head of sporangiospores. Sporangium was subglobose in shape and was 42.6-114.2$\mu$m in size. Monosporous sporangiola were elliptic, fusiform or ovoid, and brown in color and 12.3~21.6 $\times$8.3~11.6$\mu$m Um in size. Sporangiospores were elliptic, fusiform or ovoid in shape, dark brown or brown in color and 16.3~23.8$\times$8.2~13.6$\mu$m in size, and they had three or more appendages at bipolar end. Zygospores were mostly globose, dark black colored and sized was 46.2-78.4$\mu$min diameter, The fungus grew on PDA between at 15 to 4$0^{\circ}C$, and the optimum temperature was 3$0^{\circ}C$. This is the first report on the flower rot of cotton rose caused by C. cucurbitarum in Korea.