• The Korean Journal of Mycology
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• v.21 no.1
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• pp.16-22
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• 1993

Morphological and cultural characteristics of fungi causing rice sclerotial diseases were examined. Hyphal widths of R. solani and R. oryzae were same and ranged $6.0-12.0\;{\mu}m$ with average $9.0\;{\mu}m$, the widest among those of the sclerotial fungi examined. Hyphal width of R. oryzae sativae ranged $6.0-9.0{\mu}m$ with average $7.4{\mu}m$. Hyphal width of R. cerealis was the narrowest among those of Rhizoctonia species examined, and the same was hyphal width of S. oryzae among those of Sclerotium species. Nuclear staining by HCL-Giemsa method showed that R. solani and R. oryzae had many nuclei within one hyphal cell, S. oryzae one nucleus, and the other sclerotial fungi mostly two nuclei. The nuclear number of R. solani was the largest, which ranged 2-17 with average 6.3. Average size of sclerotia of the sclerotial fungi except S. hydrophilum and S. oryzae produced in lesions ranged 1.0-2.0mm. Average size of sclerotia of S. hydrophilum and S. oryzae was 0.5mm and 0.24mm, respectively. Sclerotia of R. solani and R. oryzae produced in culture were more variable in size and larger than those produced in lesions. However, the sclerotial sizes of the other sclerotial fungi produced in culture were almost the same as those produced in lesions. Sclerotial colors of sclerotial fungi produced in lesions were similar to those produced in culture, but sclerotial shapes of some sclerotial fungi exhibited somewhat difference between the sclerotia produced in lesions and in culture. Optimum temperature for mycelial growth of R. cerealis was $23^{\circ}C$, and that of the other sclerotial fungi ranged from $27\;to\;33^{\circ}C$. Maximum temperature for mycelial growth of some sclerotial fungi was as high as $41^{\circ}C$, while that of R. cerealis was as low as $31^{\circ}C$. Minimum temperature for mycelial growth of R. cerealis was $2^{\circ}C$, and that of the other sclerotial fungi ranged from $6\;to\;10^{\circ}C$.

• Journal of Conservation Science
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• v.31 no.3
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• pp.227-241
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• 2015

Fungi were isolated from mural painting in tomb no.6 at songsan-ri, Gong-ju. Antifungal susceptibility of essential oils extracted from natural medicine was tested and it confirmed applicability for mural painting in tombs. 26 species of fungi collected from air-borne and wall surfaces were identified to 15 species of Ascomycetes, 2 species of Zygomycetes, 1 of Basidiomycetes. Wheat starch and gelatin degradability were evaluated as isolated fungi. SY-18, SY-23, SY-25 showed high degradability of wheat starch. SY-18, SY-21, SY-23 were decomposed into gelatin. Biochemical characteristics of decomposing fungi to wheat starch glue and cowhide glue were analyzed by using ${\alpha}-amylase$ and gelatinase activity. An Antifungal test was conducted in Anethole and Eugenol. Anethole and Eugenol mixture(1:2) showed high antifungal susceptibility. Natural adhesives help microbial growth and can cause structural damage in mural painting. The expectation of this study is the possibility to control microbial growth in wall painting using natural essential oils. It can be used as a data for conservation method to control microbial damages.

• Journal of Forest and Environmental Science
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• v.15 no.1
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• pp.77-88
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• 1999

This experiment was carried out to compare the cultural characteristics of mycorrizal fungi associated with Pinus species, and to form mycorrhizal association with Pinus thunbergii by artificial inoculation of these fungi. Mycorrhizal fungi tested showed great variations in cultural characteristics. Most fungal isolates was best grown on MP medium, except PDA for Lepista sp.(Ln73/92). Hagem for Rhizopogon rubescens(FRI91017), and FDA for Paxillus sp.(Pa60/92). Optimum temperature for these fungi was $25^{\circ}C$, except $30^{\circ}C$ for Pisolithus tinctorius(FRI91004 and Pt1). The range of pH conditions favorable for these fungal isolates were also variable from weak acidic(pH5) to weak alkalic(pH8). Utilization of the carbon sources for these mycorrhizal fungi was different. Fructose, glucose, and maltose were all utilized well, while xylose was not utilized generally. Mycelial growth on the media supplemented with potassium nitrate was better than those on other media with urea, asparagine, or peptone as a nitrogen source, and the poor growth was observed on the media with urea. Pisolithus tinctorius(Pt1) among 7 mycorrhizal fungi artificially inoculated for the mycorrhizal synthesis on pinus thunbergii seedlings in the test tube containing a mixture of peat moss-vermiculite(2:1, v/v) formed mycorrhizae successfully after 3 months. P. tinctorius formed branched and unbranched roots covered with thick fungal mantle and radiating extemal hyphae. Mycorrhizal root cross-sectioned by hand, stained, and observed by Nomarski interference microscope showed typical characteristics of ectomycorrhizae: fungal mantle on epidermal cells and thick Hartig net hyphae around cortex cells.

• Journal of Life Science
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• v.21 no.11
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• pp.1619-1624
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• 2011

Endophytic fungal strains were isolated from the roots of six species plants in the Dokdo islands. Native plant samples, such as Artemisia japonica, Chenopodium album and Solanum nigrum were isolated from Dongdo, and those such as Cyrtomium falcatum, Dianthus longicalyx and Tetragonia tetragonoides were isolated from Seodo. In total, thirty two fungal strains were isolated from these native plants. To identify the fungal strains, polymerase chain reaction (PCR) amplification of internal transcribed spacer (ITS: containing ITS1, 5.8s and ITS2 region) regions was done with universal primers ITS1 and ITS4. Endophytic fungi of four species were isolated from A. japonica, eight species from C. album, three species from S. nigrum, three species from C. falcatum, three species from D. longicalyx and eleven species from T. tetragonoides. Culture filtrates (CF) of isolated endophytic fungi were used to treatwaito-c rice seedlings to test plant growth-promoting activity. As a result of bioassay, Ca-5-2-2 strain isolated from C. album expressed highest plant growth-promotion activity. Of all the endophytic fungi isolated, Penicillium sp., Fusarium sp. and Aspergillus sp. were the most abundantly distributed fungal strains in the six plants used in this study.

• Journal of Life Science
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• v.23 no.1
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• pp.95-101
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• 2013

In this study, plant samples of five species were collected from the Dokdo islands in South Korea. Plant samples such as Asparagus schoberioides, Corydalis platycarpa, Festuca rubra, Sedum oryzifolium, and Setaria viridis were collected from the Dongdo and Seodo. Endophytic fungal strains were isolated from the roots of five plants from the Dokdo islands. Thirty-three fungal strains were isolated from these native plants. All the endophytic fungi were analyzed by internal transcribed spacer (ITS) sequencing (ITS containing ITS1, 5.8s, and the ITS2 region). Waito-c rice seedlings were treated with fungal culture filtrates to test their plant growth-promoting activity. A bioassay of the D-So-1-1 fungal strain isolated from S. oryzifolium confirmed that it has the highest plant growth-promoting activity. All the endophytic fungi belong to four orders: Eurotiales (86%), Capnodiales (3%), Hypocreales (4%), and Incertae sedis (7%). The endophytic fungi were classified as Ascomycota, which contained Aspergillus (12%), Cladosporium (3%), Eurotium (3%), Fusarium (18%), Microsphaeropsis (6%), and Penicillium (58%) at the genus level.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.1
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• pp.77-88
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• 2010

In order to ensure good animal health and performance, it is essential to produce forages with high feeding value and good hygienic quality. However, huge amounts of forages consumed by ruminants are contaminated with mold prior to harvest or during storage as hay, straw or silage. These mold can grow in forages only when nutrients are available, correct temperature exist, oxygen is present, and unbound water is available. Fungal 'species can be divided into two groups: field fungi and storage fungi. Field fungi invade the forages while the crop is still in the field, require high moisture conditions, and are such as species of Fusarium, Alternaria, Clodosporium, Diplodia, Gibberrella and Helminthosporium. Storage fungi invade forages during storage and need less moisture than field fungi. These such as species of Aspergillus and Penicillium usually do not occur any problem before harvest. Mold growth can spoil the nutritional aspects of the forages and also results in secondary metabolites that are highly toxic to animal, humans and plants. Moldy feeds are less palatable and may reduce dry matter intake. This, in turn, leads to a reduction of nutrition intake, reducing weight gains or milk production. Performance losses of 5 to 10 percent are typical with moldy feeds. Mycotoxins are toxic substances produced by fungi (molds) growing on crops in the field or storages. While greater than 400 mycotoxins have been chemically identified, the biological or veterinary medical impact of only several mycotoxins is known. Mycotoxins have attracted considerable attention as potential causes for poor performance and health disorders in domestic livestock. They can be carcinogenic, hepatotoxic, hematotoxic, immunosuppressive, estrogenic, or mutagenic. So, feeding moldy forages has adverse effects on animal health and milk consumers. Also, this author reported that rice straw hay was contaminated mycotoxigenic fungi such as Penicillium roqueforti and Fusarium culmorum in Korea. Therefore, it is an urgent need to develop an improved post harvest storage method to reduce nutrient loss and mycotoxin contamination of forages, which will have a positive impact on human health.

• The Plant Pathology Journal
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• v.23 no.4
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• pp.287-294
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• 2007

Endophytic fungi were isolated from surface sterilized root tissues of Aralia elata and Aralia continentalis, collected from farmer's field in Chungnam province, Republic of Korea, in 2005. Based on ITS sequence analysis, 24 fungal genera were characterized from 359 isolates, belonging to 22 Ascomycota, 1 Glomeromycota and 1 Oomycota. Strumella, Rhizopycnis and Entrophospora in A. elata and Rhizopycnis and Leptosphaeria in A. continentalis were the most abundant taxa. Out of 24 genera, Entrophospora, Leptodontidium, Neoplaconema, Paraconiothyrium, Rhizopycnis, Strumella and Tumularia were new to Korea. A total of 110 isolates were tested for antifungal activities against six plant pathogenic fungi. Out of these, 39 isolates showed antifungal activity against at least one plant pathogenic fungi. Four isolates of Pyrenochaeta, 1 isolate of Entrophospora and 1 unidentified fungus strongly inhibited the growth of six plant pathogenic fungi.

• Journal of Microbiology
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• v.45 no.3
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• pp.199-204
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• 2007

The objective of this study was to evaluate the effect of soluble carbohydrates (glucose, cellobiose), pH (6.0, 6.5, 7.0), and rumen microbial growth factors (VFA, vitamins) on biohydrogenation of linoleic acid (LA) by mixed rumen fungi. Addition of glucose or cellobiose to culture media slowed the rate of biohydrogenation; only 35-40% of LA was converted to conjugated linoleic acid (CLA) or vaccenic acid (VA) within 24 h of incubation, whereas in the control treatment, 100% of LA was converted within 24 h. Addition of VFA or vitamins did not affect biohydrogenation activity or CLA production. Culturing rumen fungi at pH 6.0 slowed biohydrogenation compared with pH 6.5 or 7.0. CLA production was reduced by pH 6.0 compared with control (pH 6.5), but was higher with pH 7.0. Biohydrogenation of LA to VA was complete within 72 h at pH 6.0, 24 h at pH 6.5, and 48 h at pH 7.0. It is concluded that optimum conditions for biohydrogenation of LA and for CLA production by rumen fungi were provided without addition of soluble carbohydrates, VFA or vitamins to the culture medium; optimum pH was 6.5 for biohydrogenation and 7.0 for CLA production.

• The Plant Pathology Journal
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• v.16 no.4
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• pp.189-199
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• 2000

To search for the antifungal substances, various actino-mycete isolates were obtained from various soils of Korea using plate dilution method on the humic acid vitamin agar plates. In the screening procedures using a dual culture method, 32 actionomycete isolates were selected, which showed the inhibitory activity against mycelial growth of plant pathogenic fungi Altirnaria mali, Colletotrichum gloeosporides, Fusarium oxysporum f.sp. cucumerinum, Magnaporthe grisea, Phytophthora capsici, and Rhizoctonia solani. Bioassay of the crude extracts from culture filtrates and mycelial mets revealed that 12 antagonistic actionomycetes produced highly active antifungal substances. Actinomycete strain S5-55 which showed the substantial antifungal activity against the tested fungi was selected for production of the antifungal substances. Based on the cytochemical and morphological characteristics, strain S5-55 was identified as a Streptomyces species. The results of the numerical identification using the TAXON program confirmed that Streptomyces strain S5-55 was identical with Streptomyces humidus including in TAXON major cluster 19. The production of antifungal substance was most favorable when S. humidus strain S5-55 was cultivated for 10 dats on soluble starch broth supplemented with $K_2$HPO$_4$. The antifungal substances active against the plant pathogenic fungi P. capsici and M. grisea were partially purified using $\textrm{C}_{18}$ reversed-phase column chromatography.

• Korean Journal Plant Pathology
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• v.13 no.4
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• pp.232-238
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• 1997

Culture conditions affecting mycelial growth and sporulation of P. theae, SP2, SP3 and P. longiseta which causing leaf blight on oriental persimmon leaf blight have been investigated. The optimum temperature for the mycelial growth and sporulation on potato dextrose agar was $25{\sim}30^{\circ}C$ in all the fungi, but was inhibited and finally arrested at 10 and $30^{\circ}C$. The optimum pH for mycelial growth and sporulation were ranged at pH 4.5~5.0 and 5.0~6.0 in all the fungi. Lenonian agar, potato sucrose agar and oatmeal medium were good culture media for the mycelial growth and sporulation of all the fungi. The effective sources of nitrogen and carbon for the mycelial growth were tryptone, glycine, starch, dextrose, galactose and lactose. Glutamic acid, peptone and tryptone were good nitrogen sources for sporulation of the fungi. Sucrose, starch and galactose were also good carbon sources for sporulation. Generally, vitamins had no effect on mycelial growth and sporulation. The pH of the potato dextrose broth inoculated with SP2, SP3 and P. theae and P. longiseta was changed from 7.0 to 4.5~4.7 and 5.0~5.4 after incubating for 10 days, respectively. But, the initial pH of the medium adjusted to 5.0 was lowered to 4.5~4.7 after incubating for 10 days.