• The Korean Journal of Mycology
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• v.46 no.2
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• pp.98-104
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• 2018

The goal of this study was to elucidate wild yeast diversity of the midstream region of the Geumgang river, Gongju, Chungnam province, Korea. Fifty strains of 24 species of wild yeasts were isolated from 45 water and soil samples among which Cryptococcus spp. (11 strains), Cryptococcus magnus (7 strains), Rhodotorula spp. (9 strains), and Hanseniaspora spp. (6 strains) were dominant. Four species, Candida chauliodes WJSF 0201, Candida oleophila WJSF 0202, Candida catenulata WJSF 0203, and Candida jaroonii WJSF 0204, represented newly recorded yeasts in Korea. All of these unrecorded yeasts were oval in shape, formed ascospores and pseudomycelium, and grew in vitamin-free medium. Candida oleophila WJSF 0202 was thermophilic which can grow at $37^{\circ}C$.

• Journal of Chest Surgery
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• v.16 no.3
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• pp.281-288
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• 1983

Heparinization is an essential step in extracorporeal circulation for open heart surgery. But wide individual variation to heparin effect sometimes makes it difficult to anticoagulate safely or neutralize appropriately. Because the conventional set protocol of heparinization did not consider this individual variation, a new method of control of heparinization was proposed by Dr. Brian Bull in 1974. We compared the group in which a conventional set protocol was used [Control group] with the other in which a new protocol modified from that of Bull was used [ACT group], on the aspects of the dosages of heparin and protamine administered and postoperative bleeding. Our conventional protocol [Control group] consisted of: 1. Initial heparin was given at dose of 350U/Kg into the right atrium prior to bypass. 2. Additional heparin was given every hour during E.C.C., as much as a half of the Initial dose. 3. 600U of heparin was mixed into every 100ml. of priming solution. 4. The protamine dose was calculated by totalling the units of heparin given to the patient and giving 1 .8mg. of protamine per 100 units of heparin. ACT protocol [ACT group] consisted of: 1. Initial heparinization was same as that of conventional protocol. 2. ACT`s were checked before [A point] and 10 minutes after initial heparinization [B point]. With these 2 points, a dose response curve was drawn. 3. Heparin for the priming solution was same as in control group. 4. Every 30 minutes during E.C.C., ACT`s were checked with Hemochron [International Technidyne Corp.]. ACT between 450 and 600 seconds was regarded as safety zone. If ACT checked at a time was below 450 seconds, heparin dose was calculated on the dose-response curve to lengthen ACT to 480 seconds and was given into the oxygenator. 5. About 10 minutes before the term of E.C.C., ACT was checked to estimate the blood heparin level at the time. Then, protamine dose was calculated at dose of 1.Stag per 100 units of heparin. The calculated dose of protamine was mixed into 50 to lO0ml of 5% Dextrose Water and dripped intravenously during the period of 15 minutes. Compared these two groups mentioned above, results were obtained as follows: 1. Mean value of normal ACT checked with Hemochron on 30 preoperative patients was 124 seconds [range 95-145 sec.]. 2. Doses of heparin and protamine given to the patient were decreased in ACT group as much as 32.2% and 62.2% respectively. 3. Postoperative bleeding and transfusion were also decreased in ACT group in 60.5% and 67.1% respectively. 4. Our modified dose-response curve did not cause any problems in the control of heparinization. 5. Initial heparinization [Heparin 350U/Kg] was sufficient for the most patients until 60 minutes under extracorporeal circulation. 6. We used 1.5mg of protamine to neutralize 100 units of heparin. But smaller dose of protamine may be sufficient for appropriate neutralization.

• The Korean Journal of Mycology
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• v.10 no.1
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• pp.7-13
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• 1982

Habit characteristics of imperfect and perfect stage of D. bryoniae encountered on naturally infected seeds of cucumber and pumpkin were studied by the blotter method and compared with those grown on Difco potato dextrose agar (PDA), V-8 juice agar and water agar leaf medium (WALM). Most of the pycnidiospores obtained from each isolate of this fungus grown on PDA were non-septate and microtype. Non-septate pycnidiospores were predominanted in all isolates, but a macrotype of the non-septate and a number of uniseptate pycnidiospores were produced on V-8 juice agar and water agar leaf medium. On seed the pycnidiospores were mostly non -septate, but rarely uniseptate ones were also found. On radicle of cucumber seed, the pycnidiospores were non-septate and uniseptate but small percentage biseptate with somewhat constricted at septa. Pycnidiospores produced on V-8 juice agar and water agar leaf medium were similar to those produced on seeds. In the present investigation the perithecia were mostly globose to subglobose with apical papillate ostiole and whitish spore masses formed on the ostiole of perithecia, either on naturally infected seed or on culture media. The mature perithecia were dark brown to black. They were partially embedded or erumpent on seed coat and culture media. The perithecia varied in size within a much narrower range than the pycnidia. But perithecial formation of this fungus on PDA, V-8 juice agar, WALM and seed varied considerably depending upon isolate and culture media.

• Research in Plant Disease
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• v.12 no.2
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• pp.129-133
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• 2006

A bacterial disease of small red bean (Phaseolus angularis) was observed on field-grown plants in Suwon in year 2003. Leaf symptoms initially appeared as water-soaked spots that gradually enlarged, became flaccid and necrotic and were often bordered by a small zone of lemon yellow tissue. In the case of severe infection, dead leaves were defoliated. Pod symptoms consisted of the lesions that were generally circular, slightly sunken and dark reddish brown. Isolation made from diseased leaves on yeast extract dextrose calcium carbonate agar yielded nearly pure cultures of a yellow-pigmented bacterium typical of a xanthomonad. Three bacterial strains were purified and used for further tests. Pathogenicity of strains was confirmed on 3-week-old small red bean plants sprayed with bacterial suspensions containing $10^8 cfu/ml$ of phosphate buffered saline. The representative Xanthomonas strains isolated from small red bean were compared with X. axonopodis pv. phaseoli and X. axonopodis pv. phaseoli var. fuscans type strains for fatty acid profiles, biochemical tests and metabolic fingerprints using Biolog GN2 microplate, showing that all outcomes were indistinguishable between our isolates and reference strains. Two of three strains produced a melanin-like brown pigment extracellularly on King's medium B agar. These results suggest that this new small red bean disease observed in Suwon is bacterial fuscous blight caused by X. axonopodis pv. phaseoli and X. axonopodis pv. phaseoli var. fuscans.

• Research in Plant Disease
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• v.12 no.2
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• pp.69-74
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• 2006

Basal rot of freesia caused by a Sclerotium sp. occurred at Incheon areas. Incidence of the disease reached up to 45% and averaged 17.0% in the fields. Typical symptoms consisted of sheath dry and leaf blight due to rots on basal leaves. The causal fungus was identified as Sclerotium sp. based on following mycological characteristics. The fungus formed sclerotia on cultural media and plant tissues, but did not produce asexual spores. On cultural medium, aerial mycelia of the fungus changed color from white to clay with cultural age and smelled musty odor. Numerous irregular and elliptical black microsclerotia of the fungus were formed on potato dextrose agar (PDA) after 5 days of incubation at $25^{\circ}C$ and sized $115{\sim}200{\times}95{\sim}150 (av. 145{\sim}126.5){\mu}m$. The fungus grew at $10{\sim}32^{\circ}C$ and $pH 4.0{\sim}8.5$. However, the optimal temperature and pH for mycelial growth of the fungus were $24^{\circ}C$ and 5.5 respectively. The isolate showed present pathogenicity to not only freesia but gladiolus in the pathogenicity test, and the symptoms were similar to those observed in the fields. Basal rot of freesia caused by Sclerotium sp. is firstly reported in Korea.

• Research in Plant Disease
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• v.12 no.2
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• pp.134-138
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• 2006

A new bacterial disease of broccoli (Brassica oleracea var. italica) was observed on field-grown plants in Pyungchang during 2003 and 2004. Seedling infections first appeared as a blackening along the margins of the cotyledon. Cotyledon shriveled and dropped off. Infected seedlings were stunted and yellowed and eventually died. The disease was easily recognized by the presence of yellow, V-shaped, or U-shaped areas extending inward from margin of the leaf. As the disease progressed, the yellow lesions turned brown and the tissues died. Isolations made from diseased leaves on yeast extract dextrose calcium carbonate agar yielded nearly pure cultures of a yellow-pigmented bacterium typical of a xanthomonad. Two bacterial strains were purified and used for further tests. Pathogenicity of strains was confirmed on 3-week-old crucifer (cabbage, Chinese cabbage, kale, radish and broccoli) plants cut by scissors with bacterial suspensions containing $10^8 cfu/ml$ of phosphate buffered saline. The Biolog and fatty acid analyses and 16S rDNA sequencing of two strains (SL4797 and SL4800) from broccoli black rot showed that they could be identified as X. campestris pv. campestris because of their high similarity to the tester strain (X. campestris pv. campestris NCPPB528) with a match probability of 100%. This is the first report of black rot of broccoli in Korea.

• The Korean Journal of Mycology
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• v.49 no.3
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• pp.405-412
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• 2021

Wolfiporia cocos is an important medicinal fungus that has been used in regions of Northeast Asia including Korea, Japan, and China. W. cocos is classified in Korea into two types (red bokryeong and white bokryeong) based on the internal colors (yellow orange-pale pink and white) of the sclerotium. Generally, the W. cocos type cultivated on farms produces white sclerotium. In this study, we endeavored to select strains that form sclerotium in sawdust medium using 2-way cross-breeding among two cultivated strains and three wild strains. Monospores were isolated from the fruiting bodies of cultivated and wild strains on potato dextrose agar. Thirty-nine strains of 338 hybrid strains isolated formed sclerotia with white or yellow colors upon culture for 3 months in Pinus densiflora sawdust medium. Selection for sclerotium forming strains using sawdust culture follows a very simple and easy procedure that is presented for the first time in this paper. We plan to test selected strains in the field to aid in developing new varieties for the future.

• The Korean Journal of Mycology
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• v.49 no.3
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• pp.303-313
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• 2021

Peanuts in storage were estimated for mycotoxigenic fungi and mycotoxins. Peanut samples collected from storages in Gochang were mainly contaminated with Fusarium (17.2±28.0%), Penicillium (12.4±28.0%), and Aspergillus (8.0±7.6%). Other genera, including Talaromyces, Rhizopus, Rhizoctonia, Trichocladium, Clonostachys, Mucor, Chaetomium, Trametes, Epicoccum, and Humicola, were also found. Although aflatoxins were not detected in the peanut samples, 29 strains of Aspergillus flavus were identified using molecular marker genes. Among them, 17 selected isolates produced aflatoxins in solid culture media ranging from 0.61-187.82 ㎍/kg. All of them could produce both aflatoxin B₁ and B₂ and some (n=5) produced additional G₁, G₂, or both. This study is the first report that A. flavus stains obtained from Korean stored peanut are aflatoxigenic.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.711-716
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• 2010

'Sanggang', a new cultivar of Agrocybe aegerita, was bred with mating between monokaryotic strains isolated from 'GMAG45109' and 'GMAG45107' in Mushroom Research Station, Gyonggi Province A.R.E.S. in 2009. The optimum temperature for the mycelial growth of 'Sanggang' was 26 to 28$^{\circ}C$ on PDA(potato dextrose agar) medium. The optimum temperature for the primordia formation and fruiting body development of 'Sanggang', was 18 to 20$^{\circ}C$. In the bottle cultivation of 'Sanggang', the period of spawn running was around 38 days at 22 to 23$^{\circ}C$ and the period from scratching of inoculum to harvest was 12 days. These characteristics of 'Sanggang' were not different from those of 'Mihwang' (control). 'Sanggang' had brown-colored pileus, whereas 'Mihwang' had yellowish brown-colored one. In bottle cultivation, 'Sanggang' hada little smaller but stronger stipe and pilus than 'Mihwang', and 'Sanggang', as well as 'Mihwang', had upright stipe. And 'Sanggang' was shown to have lower veil opening ratio than that of 'Mihwang' at harvest time.The yield of fruiting bodies of 'Sanggang' was 134 g/850ml bottle, which was similar to that of 'Mihwang'. Resistance of'Sanggang' against Trichoderma spp., as well as 'Mihwang', was weak. Freshness of 'Sanggang' was maintained for 13 days under storage temperature 4$^{\circ}C$, while that of 'Mihwang' was maintained for 10 days.

• Research in Plant Disease
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• v.24 no.4
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• pp.302-307
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• 2018

From 2014 to 2016, approximately 5% of okra fruit were observed displaying gray mold symptoms at the research field of Jeollabuk-do Agricultural Research and Extension Services, Korea. The symptoms observed were water-soaked, brown or gray spots, and abundant mycelial with conidia appearing on the infected fruit. Initial infection commenced from the base of fruit and gradually moved to the pod, where it finally resulted in collapse. Colonies on potato dextrose agar were gray to grayish brown, felted and cottony expanding 65-80 mm after one week. The fungus formed several black sclerotia ranging $1.0-3.5{\times}0.5-3.0mm$ on the Petri dish after two weeks. The conidia were one-celled, ellipsoidal or ovoid, colorless or pale brown, and $6.2-15.4{\times}5.0-10.4{\mu}m$. Conidiophores arose solitary or in groups, straight or flexuous, septate, with an inflated basal cell brown to light brown, and measured $85-450{\times}10.0-40.0{\mu}m$. On the basis of the morphological characteristics and phylogenetic analyses of internal transcribed spacer rDNA, the fungus was identified as Botrytis cinerea Pers. Pathogenicity of a representative isolate was proved by artificial inoculation, fulfilling Koch's postulates. To our knowledge, this is the first report on the occurrence of B. cinerea on okra in Korea.