• Korean Journal of Microbiology
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• v.15 no.1
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• pp.20-30
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• 1977

Relationship of soil properties and seasonal variation on microbilogical population to-continuous culture and first-time culture of ginseng was investigated by bimonthly from May 1976 to January 1977. pH and P contents of 2 years continuous culture of soil were higher than other culture plot of soil, and contraty to the above, 2 years first-time culture of ginseng soil was conplot of soil, and contraty to the above, 2 years first-time culture of ginseng soil was contained more potassium contents than other culture plot of soil. In microbiological fluctuation with seasonr in various soil conditions, the population, trends of Fusarium spp., Erwiniaspp., and flourescent Psedudomonas spp. were increased in May and July in general, but decreased in the other month. It was observed that in all type of soil, Fusarium spp. was distributed in abundance in and on rihizosphere, and decreased the propagules numbers as soil depth increase. The numbers of Erwinia spp. and fluorescent Pseudo-monas spp. were distributed greater in numbers on the surface zone of soil depth decreasing the numbers along the soil layer increase, and also in 2years continuous culture of soil especially, a great numbers of Erwinia spp. and fluorescent Pseudomonas were evenly distributed in surface zone and rhizosphere. Ginseng disease with a high incidence of bacterial disease in continuous culture of 2 and 4 years was seemed to be associated with soil bacteria that was high in numbers of Erwinia spp. and fluorescent Pseudomonas spp. in May and July.

• The Korean Journal of Mycology
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• v.19 no.3
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• pp.231-237
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• 1991

This study was conducted in order to find out biological control of sesame wilt and blight caused by Fusarium of oxysporum f. sp. vasinfectum and Phytophthora nicotianae var. parasitica by using Streptomyces spp. Two sesame pathogens, Fusarium oxysporum f. sp. vasinfectum and Phytophthora nicotianae var. parasitica were purely isolated from diseased sesame plants of the field. Streptomyces species were isolated from 72 soil samples collected from red pepper and sesame uplands in Chungbuk and selected as antagonists according to the results of dual culture. The selected Streptomyces isolates such as St-11 and St-20 were confirmed their antagonistic effect through mycelial inhibition zone and inhibitory effects on the mycelial growth of the pathogens by culture filterate of the antagonists. Inhibitory effects on the conidial germination of Fusarium oxysporum vasinfectum and Phytophthora nicotianae parasitica by the antagonists were also tested in addition to mycelial Iysis. The antagonists St-11 and St-20 showed inhibitory effect on growth of sesame seedlings after seeds soaked in the suspension. Effect of soil inoculation with antagonist St-11 showed 40 to 78 percent of control effect for two diseases in comparison with control under greenhouse.

• The Plant Pathology Journal
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• v.34 no.5
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• pp.356-366
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• 2018

The red flour beetle, Tribolium castaneum, is one of the most common and economically important pests of stored cereal products worldwide. Furthermore, these beetles can act as vectors for several fungal post-harvest diseases. In this study, we collected T. castaneum from 49 rice processing complexes (RPCs) nationwide during 2016-2017 and identified contaminating fungal species on the surface of the beetles. Five beetles from each region were placed on potato dextrose agar media or Fusarium selection media after wet processing with 100% relative humidity at $27^{\circ}C$ for one week. A total of 142 fungal isolates were thus collected. By sequence analysis of the internal transcribed spacer region, 23 fungal genera including one unidentified taxon were found to be associated with T. castaneum. The genus Aspergillus spp. (28.9%) was the most frequently present, followed by Cladosporium spp. (12.0%), Hyphopichia burtonii (9.2%), Penicillium spp. (8.5%), Mucor spp. (6.3%), Rhizopus spp. (5.6%), Cephaliophora spp. (3.5%), Alternaria alternata (2.8%) and Monascus sp. (2.8%). Less commonly identified were genera Fusarium, Nigrospora, Beauveria, Chaetomium, Coprinellus, Irpex, Lichtheimia, Trichoderma, Byssochlamys, Cochliobolus, Cunninghamella, Mortierella, Polyporales, Rhizomucor and Talaromyces. Among the isolates, two known mycotoxin-producing fungi, Aspergillus flavus and Fusarium spp. were also identified. This result is consistent with previous studies that surveyed fungal and mycotoxin contamination in rice from RPCs. Our study indicates that the storage pest, T. castaneum, would play an important role in spreading fungal contaminants and consequently increasing mycotoxin contamination in stored rice.

• Korean Journal Plant Pathology
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• v.3 no.1
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• pp.8-12
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• 1987

Fusarium oxysporum, F. moniliforme, F. solani, F. equiseti, F. semitectum, and F. sporotrichioides were detected from seeds, roots and cultivated soil of Phaseolous vidissimus collected from Kyung-gi Provincial Rural Development Administration. The rate of seedling desease incidence was $60\%$ by testing of seed germination using a large petri-dish. According to the blotter method, F. moniliforme showed $7\%$ infection at seed-coat and $2\%$ at cotyledon and embryo. Their pathogenicities of F. moniliforme, F. semitectum, F. equiseti, and F. sporotrichioides isolated from seeds were recognized on seedlings by water-agar test tube methods. F. oxysporum and F. solani isolated from infected-roots had their pathogenicity by water-agar test tube method but were weakly pathogenic by soil treatment method. Their pathogenicities of F. oxysporum. F. solani and F. uiseti isolated from cultivated-soil were recognized by water-agar test tube method. These F. oxysporum and equiseti isolates had their pathogenicities but F. solani was weakly pathogenic by soil treatment method.

• Research in Plant Disease
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• v.18 no.4
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• pp.261-267
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• 2012

Inspection of deteriorated rices in Korea for fungal occurrence revealed that Aspergillus was the most frequently observed genus and some isolates of the Aspergillus spp. turned out to produce aflatoxin. Diverse fungal genera including Fusarium, Aspergillus, Penicillium, or Alternaria spp. were observed in most of the rice samples. Aflatoxin occurred infrequently and the levels of aflatoxin present in the rice samples were lower than regulatory limit but Fusarium toxins such as deoxynivalenol, nivalenol, zearalenone, and fumonisin occurred frequently. In rice processing complexes, fungal and mycotoxin contamination of rice decreased by milling process, resulting in the lowest level of mycotoxin and fungi in polished rice. Currently, it appears that Korean rice and milled by-products need a safety control for Fusarium toxins rather than aflatoxin.

• Korean Journal of Medicinal Crop Science
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• v.23 no.6
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• pp.460-467
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• 2015

Background : The aim of the present study was to identify an effective physicochemical control method to reduce Fusarium species infestation in adlay (Coix lacryma-jobi L.) before and after harvesting. Methods and Results : We observed that prochloraz emusifiable concentrate and hexaconazol prochloraz emusifiable concentrate strongly inhibited the mycelial growth of 10 Fusarium species. Strong growth inhibitions and cell lysis were observed following treatment with 4% NaOCl solution. The total number of fungi detected were lower follwing treatment with thiophanatemethyl triflumizole wettable powder ($1.1{\times}10^4CFU/g$), hexaconazol prochloraz emulsifiable concentrate ($1.2{\times}10^4CFU/g$), carboxin thiram dustable powder ($1.6{\times}10^4CFU/g$) and prochloraz emulsifiable concentrate ($1.7{\times}10^4CFU/g$) than in the non-treated control ($7.7{\times}10^4CFU/g$). The reduction of Fusarium fungi varies with the concentration and soaking time of NaOCl solution. Fungal detection was not observed after soaking in NaOCl solution for 24 h and harmful effects were not observed for plant growth by NaOCl after soacking for 6 - 12 h. Conclusion : Soaking seed for 6 - 12 h in 4% NaOCl could be an effective method of disinfectant treatment for the control of Fusarium fungi in adlay seeds.

• Korean Journal Plant Pathology
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• v.11 no.2
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• pp.158-164
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• 1995

토마토의 엽권에서 분리한 Fusariym graminearum이 분비하는 물질은 벼 도열병균(Pyricularia oryzae)의 여러 종의 식물병원 진균에 대한 항균활성을 나타내었으며, 이러한 활성물질을 PDA에서 본 균을 배양 한 후 chloroform으로 추출하여 분리정제 하였다. HPLC에 의하여 5종류의 활성 물질을 분획하였으며, 그중 1번(F402) 화합물을 벼 도열병균(P. oryzae)을 포함한 22개 식물 병원 진균에 대하여 살균 활성범위를 조사한 결과, 이 화합물은 50$\mu\textrm{g}$/ml 농도에서 Pythium ultimum, Rhizoctonia solani, Sclerotinia sclerotiorum은 전혀 억제하지 못하였으며, Phytophthora spp., Cladosporium fulvum, Fusarium spp., Corynespora cassicola에는 어느 정도의 활성이 있었지만 낮게 나타났고, P. oryzae, Cochliobolus miyabeanus, Alternaria solani는 100% 억제하여 활성이 높게 나타났다. 또한 장내 세균에 대한 활성을 MIC로 비교할 때 Streptococcus pyogenes, Streptococcus faecium에 대하여는 각각 12.5, 25 $\mu\textrm{g}$/ml였고 Staphylococcus aureus는 25-50$\mu\textrm{g}$/ml으로 나타났으며, Pseudomonas aeruginosa, Salmonella typhimurium, Klebsiella aerogenes, Enterobacter cloacae에서는 100$\mu\textrm{g}$/ml 이상으로 활성이 나타나지 않았다. F402를 200$\mu\textrm{g}$/ml의 농도로 직접 살포한 식물체에서의 방제효과는 벼도열병, 벼 깨씨무늬병, 보리 흰 가루병에 대하여는 80%이상이었으나, 벼 잎집무늬마름병, 오이 잿빛곰팡이병, 토마토 역병, 밀 녹병에서는 낮았다.

• The Korean Journal of Mycology
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• v.12 no.1
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• pp.27-33
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• 1984

Alternaria tenuis, Arthrobotrytis sp., Aspergillus spp., Cephalosporium sp., Cladosporium sp., Cylindrocarpon sp., Fusarium equiseti, F. moniliforme, F. semitectum, F. solani, Penicillium spp., Rhizopus sp. were saprophytic fungi and Cercospora kikuchii, Colletotrichum truncatum, Diaporthe phaseolorum var. sojae and Fusarium oxysporum were pathogenic fungi detected from 14 seed samples of soybean. Initial symptoms caused by C. kikuchii, C. truncatum, D. phaseolorum sojae and F. oxysporum on seedlings from naturally infected seed by the test tube agar method have been described and discussed. Soybean seeds infected with C. truncatum, D. phaseolorum sojae and F. oxysporum reduced germination of seeds and have influenced on the growth of soybean seedling caused by C. kikuchii. Surface-sterilized soybean seedlings became diseased in the test tube agar artificially inoculated with C. kikuchii, C. truncatum and D. phaseolorum sojae isolated from naturally infected soybean seeds. F. oxysporum showed very weak pathogenicity. Seed disinfectants of Benlate-T, Homai, Tecto and Sisthane have effective to C. kikuchii, C. truncatum, D. phaseolorum sojae and F. oxysporum. Arasan, Captan, Busan-30 and Mercron were inferior to C. kikuchii but effective against others. Seed disinfectants treated in this experiment have increased seed germination campared with non-treatment.

• Microbiology and Biotechnology Letters
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• v.10 no.3
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• pp.191-196
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• 1982

In order to prevent the losses of the rice by fungal deterioration during storage, fungal contaminants were isolated and identified from the grain samples (Milyang Nr.23) stored for seven months from December, 1978 to June, 1979 in silo, flat store and Tongari. Out of thirty cultures isolated from Korean paddy and brown rice samples, twenty seven species were identified, and there are eleven species of Aspergillus (A. caespitosus, A. condidus, A. chevalieri, A fischeri, A. fumigatus, A. flavus, A. nidulans, A. oryzae, A. ruber, A. sydowii, A. versicolor), five species of Penicillium (P. atramentosum, p. chrysogenum, P. cyaneofulvum, P. nototum, P. steckii), two species of each Alternaria (Al. faesiculata, Al. grisea) and Curvalaria (C, interseminata, C. tetromea), and one species of each Trichothecium roseum, Nigrospora sphaerica, Rhizopus nigricans, Fusarium spp., Mucor spp., Helminthosporium spp., and Gliocladiopsis spp. The major types of fungi grown on the surface of paddy during storage were A. flavus and A. candidus, while A. ruber and A. sydowii appeared in brown rice samples. And also A. candidus, A. versicolor and A. glacus groups were considered as major deteriorating microorganisms in stored brown and paddy rice in Korea.

• Korean Journal of Microbiology
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• v.7 no.3
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• pp.107-114
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• 1969

Relationship of soil properties and seasonal variation on microbilogical population to-continuous culture and first-time culture of ginseng was investigated by bimonthly from May 1976 to January 1977. pH and P contents of 2 years continuous culture of soil were higher than other culture plot of soil, and contraty to the above, 2 years first-time culture of ginseng soil was conplot of soil, and contraty to the above, 2 years first-time culture of ginseng soil was contained more potassium contents than other culture plot of soil. In microbiological fluctuation with seasonr in various soil conditions, the population, trends of Fusarium spp., Erwiniaspp., and flourescent Psedudomonas spp. were increased in May and July in general, but decreased in the other month. It was observed that in all type of soil, Fusarium spp. was distributed in abundance in and on rihizosphere, and decreased the propagules numbers as soil depth increase. The numbers of Erwinia spp. and fluorescent Pseudo-monas spp. were distributed greater in numbers on the surface zone of soil depth decreasing the numbers along the soil layer increase, and also in 2years continuous culture of soil especially, a great numbers of Erwinia spp. and fluorescent Pseudomonas were evenly distributed in surface zone and rhizosphere. Ginseng disease with a high incidence of bacterial disease in continuous culture of 2 and 4 years was seemed to be associated with soil bacteria that was high in numbers of Erwinia spp. and fluorescent Pseudomonas spp. in May and July.