• The Korean Journal of Mycology
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• v.12 no.3
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• pp.105-110
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• 1984

Seven seed samples of corn obtained from Kangweon Provincial Office of Rural Development, Kerea were tested for seed-borne fungi, and found that all the samples tested were infected with Fusarium moniliforme to an extent of $6.0{\sim}79.5%$. Severely infected seed samples showed poor germination on blotter. Seed component plating showed that the fungus present not only in tip caps, pericarps and endosperms, but also in embryos. Heavy infection of the fungus caused severe seed rot and seedling blight in soil, but the damage was not severe and many plants grew without any symptoms when the seeds with light infection were sown in soil. However the fungus was frequently detected from inside of the stems of healthy looking seedlings. The results indicate that the fungus transmit from seed to plant systemically. In inoculation experiments, the fungus produced stem rots on corn plants of 110 days old. The cultivar of Hwangok 3 was revealed more susceptible to the fungus than that of Suweon 19.

• The Korean Journal of Mycology
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• v.17 no.1
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• pp.1-6
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• 1989

The mycelia of Pyricularia oryzae were treated with enzyme solution mixture consisting of Driselase, ${\beta}-Glucuronidase$, Cellulase, and Macerozyme R-10 for the production of protoplasts. More protoplasts were formed from mycelia of race KJ 101 of P. oryzae than that of race KI 315a in the enzyme mixtures. The number of protoplasts was decreased in the untreated control three hrs after the enzyme treatment, whereas the number was increased in the treatments with 10, 50 and 100 mM 2-mercaptoethanol, respectively. The number of protoplasts increased to reach maximum at five hrs after treatment of 10 mM 2-mercaptoethanol, but the least was found in 200 mM. The protoplasts of P. oryzae in a liquid medium containing 2.5% yeast extract, and 2% dextrose reverted to the mycelia after five hrs shaking incubation at $27^{\circ}C$. Some protoplasts produced yeast like buds and the buds were developed to irregularly shaped chains of cell protruded a germ tube like hypha from the distal cell. Once in a while a germ tube like hypha protruded directly from the protoplasts. Except in the first type of reversion, other protoplasts reverted to the normal mycelia. The reversion frequency was highest on PDA with stabilizer of 0.6 M KCl. No reversion of protoplasts occurred on water agar regaardless oftreaatments.

• The Korean Journal of Mycology
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• v.17 no.2
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• pp.82-90
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• 1989

Detection of antibody against pathogenic fungi in serum specimens of the patients with pulmonary tuberculosis or other lung diseases has been carried out(male) using the indirect fluorescence antibody technique and immunodiffusion tests. Immunodiffusion tests revealed that 104(36.5%) out of 285 patients examined showed a positive precipitin reaction against one or more of fungal antigens. The majority of ID positive patients 64(61.5%) reacted with Aspergillus fumigatus antigen and 49(47.1%) patients reacted with Candida albicans antigen ID positive reaction to A. fumigatus was found little more frequently among male patients, while Candida albicans reactors were found more frequently among female patients. Age distribution of ID positive reactors was high(49.1-43.3%) in age group of 40-59 years, but least or none in age group of less than 30 years. Age of fungal mycelium used as antigen did not effect sensitivity of the indirect flubrescence (IF) technique in detecting antibody to A. fumigatus. Antibody class against A. fumigatus that showed highest titer was IgG and thus FITC labeled anti-IgG immunoglobulin shoul be preferable. As relatively large amount of cell wall components of Aspergilli shared antigenically, a considerable cross-reaction was observed among A. fumigatus, A. flavus and A. niger, but not much with C. albicans. While (IF) has much better sensitivity when compared with ID, relative specificity of the latter procedure cannot to be overried, so that they could be batter used together in order to obtain quantitative measurement of antibody with relative specificity.

• The Korean Journal of Mycology
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• v.42 no.3
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• pp.191-200
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• 2014

Nuruk samples collected from various regions in Korea were investigated in terms of fungal contents and diversity. In measurement of colony forming unit (CFU) in Nuruk suspensions on DRBC agar, Nuruk samples MS4, MS8, and MS10 were among the highest fungal density, with $1,278.9{\pm}21.6$ (${\times}10^4$), $1,868.0{\pm}27.7$ (${\times}10^4$), and $775.1{\pm}19.2$ (${\times}10^4$) were among the samples showing the highest fungal density. CFU per 20 mg Nuruk, respectively. The majority of fungal components were yeasts, including Pichia anomala, P. kudriavzevii, Kluyveromyces marxianus, and Saccharomycopsis fibuligera, whereas Aspergillus oryzae and Rhizopus oryzae, the representative Nuruk fungi, were predominant only in the low fungal density Nuruks (MS2, MS5, and MS11). Saccharification capability of the fungal isolates was assessed by measurement of amylase activity in the culture broth. The highest amylase activity was found in A. niger and A. luchuensis, followed by S. fibuligera. A. oryzae and R. oryzae showed fair amylase activity but significantly lower than those of the three fungal species. R. oryzae was suggested to play an additional role in degradation of ${\beta}$-glucan in crop component of Nuruk since R. oryzae was the only fungus that showed ${\beta}$-glucanase activity among the fungal isolates. To confirm the safety of Nuruk, aflatoxigenicity of the isolated Aspergillus was estimated using the DNA markers norB-cypA, aflR, and omtA. All of the isolates turned out to be non-aflatoxigenic as evidenced by the deletion of gene markers, norB-cypA and aflR, and the absence of aflatoxin in the culture supernatants shown by TLC analysis.

• The Korean Journal of Mycology
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• v.29 no.1
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• pp.1-8
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• 2001

To examine the structural properties of the proteoglycan (GMPG, Ganoderma lucidum mycelial proteoglycan) obtained from mycelia in Ganoderma lucidum IY009, we obtained the low and high molecular proteoglycan by ultrafiltration and sepharose CL-4B column chromatography. The physicochemical properties of these fractions were as follows. When the proteoglycan separated by ultrafiltration and sepharose CL-4B column chromatography, its was not fractionated completely. The molecular weight of high molecular proteoglycan by the gel column chromatography (CH) was 250 kD and 2,000 kD, and low molecular proteoglycan was 12kD. The total carbohydrate was consisted of 75.7% (UH) and 96.7% (CH), and the low fraction was 72.7% (UL) and 87.1% (CL), respectively. The sugar of high and low molecular proteoglycan composed of glucose, mannose, fructose, galactose, xylose, ribose and arabinose. Glucose contents of all fraction were ranged from $46.9%{\sim}82.4%$ of the total sugar and the ratio of ${\alpha}$\;and\;{\beta}-glucose$ was $0.84{\sim}1.14$, and its indicated the proteoglycan to be ${\beta}-glucan$. Amino acids pattern showed that the fractions contained a large amount of aspartie acid, glutamic acid, alanine and leucine. These fractions showed the characteristics of IR absorption for ${\beta}-glucan$ at $890\;cm^{-1}\;and\;^{13}C-NMR$ spectroscopy showed the presence of the ${\beta}-1,3-glucan$ and a ${\beta}-1,6-glucan$.

• The Korean Journal of Mycology
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• v.41 no.2
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• pp.57-66
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• 2013

The mushrooms collected at seven areas of Mt. Chiak in 2002 and 2003 were classified to analyse the distribution and species diversity. Frequency (number of mushroom : N), number of species (S), relative species density (RSD), similarity index (C), richness index (R1), variety index (V1), evenness index (E2), and dominance index(D1) were investigated. Total N and S was 143 and 84, respectively. The RSD was 0.179 ~ 0.226 of the 7 areas. The yearly C of the total area (0.213) was 8.2%. more higher than the average C of 7 areas (0.131). The order in the coefficient of variation (CV) of the indicator for 7 areas was N (10.5%) > D1 (9.2%) > V1 (8.9%) > S (8.5%) > R1 (7.4%) > E2 (2.2%). The average R1 of the 7 areas was 5.36 with the range from 4.85 to 6.01, and 16.72 for the total area. The average V1 of the 7 areas was 16.24 with the range from 14.44 to 18.66, and 68.82 for the total area. The average E2 of the 7 areas was 0.95 with the range from 0.926 to 0.982, and 0.819 for the total area. The average D1 of the 7 areas was 0.071 with the range from 0.055 to 0.073, and 0.081 for the total area. The correlation between N and 5 kinds of diversity indicator (S, R1, V1, E2, D) was not statistically significant, but the correlation between R1, E2 and D1 was statistically significant each other.

• The Korean Journal of Mycology
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• v.24 no.2 s.77
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• pp.155-165
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• 1996

This study was carried out to identify the phylogenetic relationship among several isolates of Pleurotus species by comparing ITS II region of ribosomal DNA(rDNA) repeat unit. Two primers from ribosomal DNA sequences were chosen to amplify the specific internal transcribed spacer (ITS) II region of Pleurotus spp. The exact ITS II region with an unique band from six species of Pleurotus genus could be amplified using the two primers taken from at the 3'-end of 5.8S rDNA and 5'-end of 28S rDNA. Six representative species of the Pleurotus genus were easily characterized according to the length differences of ITS II region. Furthermore, within P. ostreatus species, different sizes of ITS II region could be observed in the isolates of ASI 2025 and ASI 2095 although they were classified as P. ostreatus by the conventional observation. The nucleotide sequence analyses of PCR-amplified ITS II region indicated that the isolates ASI 2025 and ASI 2095 were different from other Pleurotus spp. When the nucleotide sequences of six Pleurotus species were compared, three typical ITS II regions were highly variable especially at both ends of this region. The phylogenetic tree obtained by the Neighbor program of Felsenstein PHYLIP package with all the nucleotide sequence of Pleurotus spp. indicated that P. ostreatus, P. florida, P. sajor-caju and P. eryngii were closely related to one phylogenetic branch and P. cystidious was related to other branch with P. cornucopiae. The isolates ASI 2025 and 2038, however, were not closely related to any other Pleurotus spp. and formed their own individual branches.

• The Korean Journal of Mycology
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• v.32 no.2
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• pp.79-88
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• 2004

Cordyceps pruinosa grows upon dead pupae of Lepidoptera and produces one or $3{\sim}4$ club-shaped stromata per host. The stromata have distinct club-shaped head and long stalk. The length of stromata varies from $1{\sim}3\;cm$. Apical head consists of densely crowded semi-immersed perithecia, which are $360{\sim}400\;{\times}\;180{\sim}200\;{\mu}m$ in size. Asci are $150\;{\mu}m$ in length and $2.8{\sim}3\;{\mu}m$ in diameter. Ascospores, which are $124{\sim}141\;{\mu}m$ in length, have thin thread-like structures in the middle with part-spores attached on both sides. Each ascospore does not separate into part-spores after dispersal, but each part-spore germinates and together develops a colony. The imperfect form produces phialides of $15{\sim}24\;{\times}\;2{\sim}3\;{\mu}m$ size, with spherical or spindle shaped conidia of $4{\sim}6\;{\times}\;1.8{\sim}2.4\;{\mu}m$ size, The anamorph was identified as Mariannaea elegans Samson. YMA and SDAY agar media with pH 7 was produced abundant mycelial growth with high density. Best mycelial growth was observed when dextrin was used as a carbon source. Lactose, saccharose and sucrose also produced high mycelial growth. Peptone, yeast extract and tryptone produced abundant mycelial growth, when used as nitrogen sources. Highest mycelial growth and density was observed when C/N ratio was 1 : 1 at the concentration of 12.5 g/l each. $KH_2PO_4$ was the best mineral source for mycelial growth. Highest mycelial dry wt. was produced in YM and SDAY broths. Optimum inoculum for 100 ml of liquid broth was 6 mycelial discs. Similarly, optimum liquid culture period was 7 days.

• The Korean Journal of Mycology
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• v.16 no.1
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• pp.41-48
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• 1988

To investigate germination characteristics of soils on Fusarium species under different soil conditions, this study was carried out to test spore germination of 4 Fusarium species. Among 102 soil samples, spore germinations of Fusarium solani f. sp. pisi, F. oxysporum f. sp. cucumerium, F. oxysporum f. sp. raphani and F. coccophilum were under 50% in 98, 85, 82 and 83 soil samples, respectively. The highest spore germination of F. solani f. sp. pisi, F. oxysporum f. sp. cucumerium and F. coccophilum was obtained in 21 soil samples of pH 5.1-6.0, whereas F. oxysporum f. sp. raphani was in 33 soil samples of pH 4.1-5.0. The highest spore germination of F. solani f. sp. pisi, F. coccophilum and F. oxysporum f. sp. cucumerium was obtained in 4 soil samples holding soil moisture content of 41-60%, while F. oxysporum f. sp. raphani was in 22 soil samples of 21-30%. F. oxysporum f. sp. raphani only showed a direct correlation(r=0.29) between spore germination and soil moisture content. On the basis of each spore germination in cultivated and non-cultivated soils, there was significant difference(p=0.01) in 4 Fusarium species. F. solani f. sp. pisi only indicated significant difference(p=0.0l) between two contrasting-soils, cultivated and non-cultivated soils. The numbers of microbial population were higher in soils suppressive to spore germination than soils conducive to spore germination.

• The Korean Journal of Mycology
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• v.5 no.1
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• pp.13-19
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• 1977

In order to investigate histopathologically the nature of varietal resistance and infection process of the rice bast fungus, Pyricularia oryzae. this experiment was undertaken by using the resistant cultivar Tongil and susceptible cultivars Norin No.6 and Jinheung in 1973 to 1974. 1) It was found that appressorium of the fungus forms not only at 4 hours after incubation under the favorable conditions but also peak of appressorial formation is at 48 hours treatment. Physical stimulus known to be a definite factor for appressorial formation. The optimum temperature range for appressorial infection was at $24^{\circ}C$ to $28^{\circ}C$, and pH was between 4.8 to 8.0 with 6.8 as the optimum. 2) Although percent of appressorial formation on the leaves of resistant Tongil and susceptiible Norin No.6 were only slightly different, there was a remarkable difference between resistant and susceptible cultivars with regard to percent of hyphal infection and index for hyphal extension. Index of hyphal extension was 1.6-2.7 in Tonyil. while in susceptible cultivar was 3.4-6.6. The rate of discoloration of infected cells, a indication of hypersensitivity, was greater in the resistant than in susceptible cultvar. 3) Therefore, it could be concluded that resistance of Tongil cultivar may be attributable to a higher degree of mechanical barriers as well as a higher level of antifungal substance accumulation.