• The Plant Pathology Journal
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• 제24권1호
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• pp.52-57
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• 2008

Twenty isolates of Bacillus spp. obtained from livestock manure composts and cotton-waste composts were tested for in vitro antagonistic effects against soilborne plant pathogenic fungi, Fusarium oxysporum, Phytophthora capsici, Rhizoctonia solani AG-4, and Sclerotinia sclerotiorum. Seven isolates of Bacillus spp. had antagonistic effects on mycelial growth of all the isolates of F. oxysporum tested. The bacterial isolate RM43 was the most effective to inhibit the mycelial growth of the fungal isolates. Twelve isolates of Bacillus spp. had antagonistic effects on mycelial growth of all the isolates of P. capsici tested. The bacterial isolates M34 and M47 were very effective to inhibit the mycelial growth of the fungal isolates. Thirteen isolates of Bacillus spp. had antagonistic effects on mycelial growth of all the isolates of R. solani AG-4 tested. The bacterial isolates M27 and M75 were very effective to inhibit the mycelial growth of the fungal isolates. Fourteen isolates of Bacillus sp. had antagonistic effects on mycelial growth of all the isolates of S. sclerotiorum tested. The bacterial isolates M49 and M75 were very effective to inhibit the mycelial growth of the fungal isolates. The antagonistic effects of most Bacillus spp. isolates against the isolates of the four fungi differed depending on the fungal species and the isolates of each fungus. The bacterial isolates M27 and M75 were the most effective to inhibit the mycelial growth of all four fungi.

• Mycobiology
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• 제33권4호
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• pp.178-181
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• 2005

Cordyceps militaris specimens were continuously collected by Entomopathogenic Fungal Culture Collection (EFCC), Kangwon National University from different mountains, national parks and recreation parks of Korea from 1986 to 2002, mainly from late May to October of each year. Dry specimens of C. militaris along with their isolates have been preserved in EFCC. Fruiting of C. militaris was induced from single ascospore isolates as well as their combinations in brown rice medium. Fruiting experiments showed that combinations of single ascospore isolates produced fertile fruiting bodies, but single isolates could not produce any fruiting bodies. It was shown that two isolates of the opposite mating types were required to produce fertile stromata. However, combinations of the same mating type isolates produced no fruiting body, showing that C. militaris is a bipolar, heterothallic fungus.

• Mycobiology
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• 제35권4호
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• pp.230-234
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• 2007

In order to breed a Cordyceps bassiana isolate that stably forms fruiting body in artificial cultivation, isolates derived from subculturing and single spores were tested through mating. From C. bassiana EFCC 783, three subcultured isolates EFCC 2830, EFCC 2831 and EFCC 2832 were obtained and fourteen single conidial isolates were obtained from these three subcultured isolates. Two different morphological types were found in the fourteen single conidial isolates. One type was able to form synnemata and another type was not able to form synnemata. Since switch of morphological type was not observed despite their continuous subculturing, cross was performed between the two types and the formation of fruiting body was examined. Ascospores were obtained from a selected fruiting body formed by hybrid of the cross. Self-cross and combinational cross of the ascospore-derived isolates generated hybrids that stably produce high quality fruiting body in artificial media.

• Mycobiology
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• 제45권3호
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• pp.150-159
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• 2017

This study analyzed the distribution of endophytic fungi in 3 coastal environments with different climatic, geographical, and geological characteristics: the volcanic islands of Dokdo, the East Sea, and the West Sea of Korea. The isolated fungal endophytes were characterized and analyzed with respect to the characteristics of their host environments. For this purpose, we selected common native coastal halophyte communities from three regions. Molecular identification of the fungal endophytes showed clear differences among the sampling sites and halophyte host species. Isolates were also characterized by growth at specific salinities or pH gradients, with reference to previous geographical, geological, and climate studies. Unlike the East Sea or West Sea isolates, some Dokdo Islands isolates showed endurable traits with growth in high salinity, and many showed growth under extremely alkaline conditions. A smaller proportion of West Sea coast isolates tolerate compared to the East Sea or Dokdo Islands isolates. These results suggest that these unique fungal biota developed through a close interaction between the host halophyte and their environment, even within the same halophyte species. Therefore, this study proposes the application of specific fungal resources for restoring sand dunes and salt-damaged agricultural lands and industrialization of halophytic plants.

• Ocean Science Journal
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• 제42권4호
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• pp.247-254
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• 2007

Marine bacteria, actionmycetes and fungal strains were isolated from continental slope sediment of the Bay of Bengal and studied for fatty acid profile to investigate their involvement in the benthic food-web. Fifteen different saturated and unsaturated fatty acids from bacterial isolates, 14 from actinomycetes and fungal isolates were detected. The total unsaturated fatty acids in bacterial isolates ranged from 11.85 to 37.26%, while the saturated fatty acid ranged between 42.34 and 80.74%. In actinomycetes isolates, total unsaturated fatty acids varied from 27.86 to 38.85% and saturated fatty acids ranged from 35.29 to 51.25%. In fungal isolates unsaturated fatty acids ranged between 44.62 and 65.52% while saturated FA ranged from 20.80 to 46.30%. The higher percentages of unsaturated fatty acids from the microbial isolates are helpful in anticipating the active participation in the benthic food-web of Bay of Bengal.

• Korean Journal Plant Pathology
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• 제10권4호
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• pp.297-304
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• 1994

This study was carried out to develop bioassay for detection of pesticide residues in agricultural products by using the soil microbial isolates sensitive to pesticides. One hundred bacterial isolates and eighty five fungal isolates were obtained from soil and their sensitivity to 10 ppm of several pesticides was examined in vitro. Five bacterial isolates and three fungal isolates were found sensitive to organochloride fungicide and two fungal isolates sensitive to organocopper fungicide. Among these isolates, B46, B93 and F67 were tested to find out the difference in sensitivity according to the methods of fungicide treatment. All of the isolates were found sensitive to 10 ppm of organochloride fungicides mixed directly in PDA. But they were found insensitive to the fungicide mixed in PDA after filtering through membrane filter. In case of organocopper fungicide, the isolates were found sensitive only when it was treated in PDA. And their sensitivity showed difference among various kinds of organochloride fungicides. B46 and B93 were employed to check the possibility as the agent for detection of the pesticidal residues in twenty eight agricultural products including rice. It was found that all samples had not residues because the samples did not inhibit the growth of isolates. When organochloride fungicides were applied to the above products, it was possible to detect the residues in fruits and vegetables at the concentration of 10 ppm, but not in starch-rich grains. B46 and B93 were identified as Bacillus sp. according to their bacterial characteristics in culture.

• The Plant Pathology Journal
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• 제35권6호
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• pp.598-608
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• 2019

Endophytic fungi have received much attention as plant growth promoters as well as biological control agents against many plant pathogens. In this study, 30 endophytic fungal species, isolated from various plants in China, were evaluated using in vitro dual culture assay against Fusarium oxysporum f. sp. cucumerinum, causing wilt in cucumber. The results of the present study clearly showed that all the 30 endophytic fungal isolates were highly capable of inhibiting the mycelial colony growth of Fusarium oxysporum f. sp. cucumerinum with inhibition % over 66% as compared to control treatments. Among all of them, 5 isolates were highly effective such as, Penicillium sp., Guignardia mangiferae, Hypocrea sp., Neurospora sp., Eupenicillium javanicum, and Lasiodiplodia theobromae, respectively. The Penicillium sp. and Hypocrea sp. were highly effective as compared to other isolates. From in vitro results 10 best isolates were selected for greenhouse studies. The results of the greenhouse studies showed that among all of them 3 endophytic fungal isolates successfully suppressed wilt severity when co-inoculation with pathogen Fusarium. oxysporum f. sp. cucumerinum. The endophytic fungi also enhanced plant growth parameters of the host plants, the antagonistic fungal isolates increased over all plant height, aerial fresh, and dry weight as compared to control.

• The Korean Journal of Mycology
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• 제24권4호통권79호
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• pp.280-292
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• 1996

The fungal isolates of Mucorales, directly collected from Korean traditional raw materials of Nuruk (raw material for Korean rice wine) and Meju (raw material for Korean soysauces), were compared with those of Rhizopus oryzae purchased. The fungal isolates of Rhizopus, Mucor, and Absidia mostly identified as based on the morphological observations, were evaluated with the PCR-polymorphic bands. The PCR-polymorphic bands of the genomic DNA reacted with the primers of OPD series tenmer were various, but showed averaged 4 to 6 in the agarose-electrophoresis. The dissimilarity coefficient (DC) between two isolates were compared by the cluster analyses, dendrogams and polar ordinations. The isolates of R. oryzae known. showed several groupings within the lower value of DC and were divided to two groups of amylo-process and other fungi with other purposes. The isolates unidentified were identified by the DC made of this results. Taxonomy of these isolates made by the morphological observations were consistent with those resulted above in most case but not in all aspects. More works were needed with the isolates known for detail informations of Mucorales.

• Mycobiology
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• 제35권2호
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• pp.100-102
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• 2007

Pet dogs have been considered to be involved in the contamination of indoor air by serving as a source of providing molds at houses. Currently, information on the molds originated from pet dogs is rarely available in Korea. The present study was carried out to obtain basic information on the fungi present on pet dogs. For this, fungal isolation was performed to the skin and hairs of 70 pet dogs at different houses and veterinary hospitals. A total of 44 fungal isolates were obtained from skin (27 isolates) and hairs (17 isolates) of the dogs investigated. Based on the observation of microstructures and colony morphology, and the ITS rDNA sequence analysis, the fungal isolates were identified at the level of genus. The identified isolates belong to the genera of Alternaria, Aspergillus, Beauveria, Chrysosporium, Cladosporium, Penicillium, Scopulariopsis, and Trichoderma. Among these genera, Aspergillus (25%), Cladosporium (23%) and Penicillium (20.5%) were 3 major genera. 63% of the 44 isolates showed color changes on dermatophyte test medium (DTM). When we tested the growth ability of 44 isolates at $37^{\circ}C$, 45% of the isolates were able to grow. These results show that pet dogs could carry fungi having a potentiality of affecting on human health.

• The Plant Pathology Journal
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• 제33권2호
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• pp.118-124
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• 2017

Bell pepper is an economically important crop worldwide; however, production is restricted by a number of fungal diseases that cause significant yield loss. Chemical control is the most common approach adopted by growers to manage a number of these diseases. Monitoring for the development to resistance to fungicides in pathogenic fungal populations is central to devising integrated pest management strategies. Two fungal species, Fusarium incarnatum-equiseti species complex (FIESC) and Colletotrichum truncatum are important pathogens of bell pepper in Trinidad. This study was carried out to determine the sensitivity of 71 isolates belonging to these two fungal species to fungicides with different modes of action based on in vitro bioassays. There was no significant difference in log effective concentration required to achieve 50% colony growth inhibition ($LogEC_{50}$) values when field location and fungicide were considered for each species separately based on ANOVA analyses. However, the $LogEC_{50}$ value for the Aranguez-Antracol locationfungicide combination was almost twice the value for the Maloney/Macoya-Antracol location-fungicide combination regardless of fungal species. $LogEC_{50}$ values for Benomyl fungicide was also higher for C. truncatum isolates than for FIESC isolates and for any other fungicide. Cropping practices in these locations may explain the fungicide sensitivity data obtained.