• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.199-205
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• 2004

The effect of chitosan on enzymatic activities and on bioactive compounds was characterized during germination at $25^{\circ}C$ for 7 days to search for a method to produce a germinated black rice. The germination rate was reduced by the addition of lactate and chitosan. The rotting rate was greatly decreased by chitosan, suggesting that the addition of chitosan into a germination solution might be an effective method for controlling fungal contamination during the germination of cereals. The addition of 100 and 200 ppm chitosan increased $\alpha$-amylase activity after 7 days by up to 152 % and 197 %, respectively. The activities of $\beta$-amylase and $\beta$-glucosidase were lower with 200 ppm chitosan than in distilled water and 100 ppm lactate. The amount of total soluble phenolics and total flavonoids decreased rapidly for four days and thereafter remained constant until the seventh day. The antioxidant activity of germinated black rice, in terms of hydrogen-donating activity, increased slowly and did not correspond to the changes of total soluble phenolics and total flavonoids. The amount of phytic acid was reduced by the addition of 200 ppm chitosan compared to distilled water, indicating that chitosan could be used as an elicitor for the increase of phytase activity during the germination of black rice.

• 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.

• The Korean Journal of Mycology
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• v.36 no.2
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• pp.203-205
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• 2008

From 2006 to 2008, the stem rot of Petunia hybrida Vilm. caused by Sclerotium rolfsii occurred sporadically at Jinju city in Gyeongsangnam-do. The typical symptom is water-soaking, brown on the stem and rotting, wilting and blighting. The infected plants were mostly died. White mycelial mats were spread over lesions, and then sclerotia were formed on stem and near soil line. The sclerotia were globoid in shape, $1{\sim}3\;mm$ in size and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation was at $30^{\circ}C$ on PDA and the hyphal width ranged from 4 to $8{\mu}m$. The typical clamp connections were observed in the hyphae of the fungus. On the basis of mycological characteristics and pathogenicity to P. hybrida, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report on the stem rot of P. hybrida caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.17 no.1
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• pp.75-77
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• 2011

Gray mold caused by Botrytis cinerea occurred on Saintpaulia ionantha in flower shop of the Jeonju city in Korea. Typical symptoms with brown water-soaked and rotting lesions were appeared on the flowers, leaves and petiole of infected plants. Many conidia spores appeared on the lesions under humid conditions. Colonies were grayish brown and sclerotial formation on potato dextrose agar. Conidia were one celled, mostly ellipsoidal or ovoid in shape, and were colorless to pale brown in color. The conidia were $7{\sim}14{\times}5{\sim}9\;{\mu}m$ in size. Based on pathogenicity and morphological characteristics of the isolated fungus, the causal fungus was identified as B. cinerea Persoon: Fries. Gray mold of S. ionantha was proposed to the name of this disease.

• Korean Journal of Microbiology
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• v.13 no.1
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• pp.37-44
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• 1975

As a basic study to elucidate nutritional physiology and composition of synthetic medium of red rotting bacteria, Erwinia carotovora, of ginseng, the effects of hydrogen ion concentration, various kinds of carbon sources, nitrogen source, micrometallic salts and it's concentration on the gorwth of the bacteria were investigated and the results were as follows. Optimal pH in the basal medium for the growth of the bacteria was 6.5. After incubation the pH in culture media was neutralized. Among the various kinds of carbon sources, sucrose, glucose mannitol, but organic acids were not utilized effectively as nutrients. After incubation the pH turned acidic. Alanine as organic nitrogen sources nad ammonium sulfate as inorganic nitrogen promoted the growth, but L-valine and sodium nitrite were the least effective. Ferric chloride 1.0mg/dl and ferrous sulfate 100mg/dl were the most effective as micrometallic sources. Control and boric acid were the least effective. New synthetic medium based on the above results was follows ; Alanine 1.0g, $KH_2PO_4$ 1.0g, sucrose 30.0g, $MgSo_4$ $7H_2$O 0.5g, $FeCl_36H_2$O 1.0mg thiamine 200.gamma.g, and distilled water 1000ml, pH6.5.

• The Korean Journal of Mycology
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• v.37 no.2
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• pp.198-200
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• 2009

From 2008 to 2009, the stem rot of Astragalus sinicus L. caused by Sclerotium rolfsii occurred sporadically in Gyeongnam area, Korea. The typical symptom is water-soaking, rotting and wilting on the stem. The infected plants were eventually died. White mycelial mats were spread over lesions, and then sclerotia were formed on stems and near soil line. The sclerotia were globoid in shape, white to brown in color, 1-3 mm in size and the hyphal width was 3-9 μm. The optimum temperature for mycelial growth and sclerotial formation on PDA was 30oC. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report on the stem rot of A. sinicus caused by S. rolfsii in Korea.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.205-207
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• 2010

Stem and petiole rot symptoms of Valeriana fauriei occurred sporadically in the herb exhibition field in Gyeongsangnam-do Agricultural Research and Extension Services, Hamyang-gun, Gyeongnam Province in Korea. The typical symptom is water-soaking on the stem, rotting, wilting, blighting and the infected plants eventually died. White mycelial mats spreaded over lesions, and then sclerotia were formed on the infected plant parts and near soil surface line. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii. This is the first report of stem rot on Valeriana fauriei caused by Sclerotium rolfsii in Korea.

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.473-477
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• 2004

Wasabis (Wasabia japonica Matsum.) have been used as a spice with its petioles and rhizomes, but the production of its rhizomes in upland cultivation was very difficult for the severe damage of rotting disease during summer season. This experiment was carried out to increase the yield of marketable rhizome in wasabi when cultured in upland. Seedlings were raised in sub-alpine area for 7 and 12 months and then transplanted to experimental area on Sept. 20 and the yield was investigated on May 12 of the next year. The marketable rhizome(above 40g/plant) was produced in seedlings raised for 7 months. Production rate of marketable rhizome was 13.3% and total yield was 72.9 kg/10a. The content of allylisothiocyanate in rhizome of upland wasabi was 0.777 mg/g and its content was equal to wasabi cultured in water condition for 18 months. These results suggested that the upland cultivation of wasabi seedlings raised in sub-alpine area for 7 months was possible to product marketable rhizome.

• Research in Plant Disease
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• v.14 no.2
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• pp.131-133
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• 2008

From 2006 to 2007, the stem rot of Elsholtzia splendens Nakai caused by Sclerotium rolfsii occurred sporadically in an herbs exhibition at Gyeongsangnam-do Agricultural Research and Extension Services, Korea. The typical symptom is water-soaking, dark brown on the stem and rotting, wilting and blighting. The infected plants were mostly died. White mycelial mats were spread over lesions, and then sclerotia were formed on stems and near soil line. The sclerotia were globoid in shape, $1{\sim}3$ mm in size and white to brown in color. The optimum temperature and sclerotia on PDA was $30^{\circ}C$ and the hyphal width was $4{\sim}9{\mu}$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report on the stem rot of E. splendens caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.17 no.2
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• pp.222-224
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• 2011

The sclerotium rot of onion (Allium cepa L.) was occurred sporadically in the farmer's fields at Daehap, Changnyeong in Korea. The typical symptom was water-soaking on the bulb, stem and leaves and then rotting, wilting, blighting and the infected plants eventually were rotted and died. The sclerotia were globoid, 1-3 mm, and white to brown. The optimum temperature for mycelial growth and sclerotial formation on PDA was $30^{\circ}C$. The hyphal width was 4-9 ${\mu}m$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. On the basis of mycological characteristics, ITS rDNA sequence analysis, and pathogenicity, this fungus was identified as Sclerotium rolfsii Saccardo. To our knowledges, this is the first report of sclerotium rot on onion caused by S. rolfsii in Korea.