• 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 $6\;to\;10^{\circ}C$.

• The Korean Journal of Mycology
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• v.42 no.1
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• pp.57-63
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• 2014

This study was carried out to obtain morphological and physiological characteristics of ear mushrooms for an artificial cultivation. Eighteen strains were cultivated with bag culture and classified into mainly five groups such as brown, black, white, purple and others group. The highest yield was shown in 43007 strain as 98.3 g/bag and 43009, 43016, 43025 and 44035 strains were more than 60 g/bag. Among collected strains, 43007, 43009 and 43035 were selected in this study as superior strains. Three selected strains were investigated for optimal mycelial growth conditions. MCM and GPYM media were selected for the favorable culture medium. The carbon sources of 43007, 43009 and 43035 on mycelial growth were maltose, fructose and glucose, respectively and peptone was selected as a nitrogen source. Highest mycelial growth was observed when the C/N ratio was 10 for 43007 and 20 for 43009 and 43035.

• Research in Plant Disease
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• v.26 no.2
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• pp.61-71
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• 2020

With 32 fungicides, it was examined the inhibitory effects on the mycelial growth of Alternaria dauci KACC42997 causing Alternaria leaf blight of carrot. Showing the results of the agar dilution method, the fungicides belonging to C2, C5, G1, E2, and E3 group were excellent in inhibiting mycelial growth. Protective fungicides belonging to M group, except for iminoctadine tris-albesilate, and pyraclostrobin belonging to C3 group were effective in inhibiting spore germination of pathogens. The fungicides included into C2 group inhibiting succinate dehydrogenase activity and the G1 group inhibiting demethylase activity showed the excellent inhibitory effect on mycelial growth but the inhibitory effect of spore germination was very low. However, fluazinam belonging to C5 group was excellent in inhibiting spore germination as well as mycelial growth. Especially, when 100 ㎍/ml of fluxapyroxad belonging to the C2 group was treated, 47.1% of spore formation was inhibited on the medium. In comparison of the resistance factors of 3 fungicide groups, as G, C, and E group, in populations of A. dauci isolates collected from Gumi, Pyeongchang, and Jeju, resistance factor in the population of Jeju was the lowest. However, two isolates resistant to fludioxonil belonging to E2 group were found in the isolate group of Pyeongchang, and both showed cross-resistance to iprodione and procymidone.

• The Korean Journal of Mycology
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• v.36 no.2
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• pp.172-177
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• 2008

Mycelial growth of Pleurotus ostreatus isolates was examined on PDA media added with heavy metals to reveal effects of heavy metals on mycelial growth of the fungus. Cd and Cu strongly inhibited mycelial growth of three isolates of fungus tested. However, addition of $2{\sim}10\;mM$ Pb to growing media of white color mutant of fungus resulted in increase of the fungal growth rate. Addition of 2 mM Cr to the media resulted in increase of growth rate of the white color mutant and the dark color mutant of fungus. Mycelial growth rate of the white color mutant was relatively better than the other isolates on media added with Cr, Pb, Cu, or Mn, respectly. Tolerance of the white color mutans to heavy metals was higher than that of the black color mutant. It is suggested that tolerance of the white color mutant to heavy metals was not controled by color-related substance of the fungus.

• Journal of Practical Agriculture & Fisheries Research
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• v.3 no.1
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• pp.70-78
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• 2001

The objective of this study was to determine effects of corn germ meal(CGM) and condensed molasses fermentation solubles(CMS) as the replacement of rice bran on mycelial growth and density in various mushrooms. The results of this study showed that CGM and CMS might be utilized more efficiently than rice bran in culturing mushrooms. The results are as follows; 1. Mycelial growth of Pleurotus ostreatus was remarkably higher than that of control when the concentration of CGM and CMS was 10%, respectively. However, the mycelial density was lower than that of control. Thus, Considering the mycelial growth as well as density, it was found that 20% supplements of CGM and CMS resulted in the best with 78mm/10d and 71mm/10d, respectively. 2. Mycelial growth of Pleurotus eryngii in the treatment group of 10% CMS and 20% CGM showed 74mm/10d and 67mm/10d, respectively. This result tended to be equal or somewhat lower compared with that of control(74mm/10d). 3. Mycelial growth of Flamulina velutipes was 87mm/10d in the treatment of 10% CMS, 79mm/10d in the treatment of 20% CGM, which showed significantly higher than that of control(56mm/10d). When the contents of CGM and CMS were mixed with the amount of 10-30%, Thus, it was assumed that the quantity of mushrooms may increase with the supplements of CEM and CMS. 4. Mycelial growth of Lentinus edodes in the treatment group of 10-40% CMS and 10-30% CGM showed 58-52mm/10d and 56-49mm/10d, respectively. This result was significantly higher that control(47mm/10d). 5. When CMS and CGM were supplememted with the level of 10-30%, mycelial growth rate of Ganoderma lucidum showed 76-72mm/10d and 74-69mm/10d, respectively, which are higher than those of control.

• Journal of Mushroom
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• v.9 no.3
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• pp.110-115
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• 2011

Trichoderma disease of oyster mushroom has not been effectively detected in the field for testing its resistance against the disease with its varieties. In this study, we investigated the methods to detect its resistance in the laboratory by using media, which enables us to understand the relevant characteristics (e.g., lysis, toxin enzyme, mycelial growth rate). In coculturing with strains of Trichoderma and oyster mushroom, it is possible to observe the difference in the resistance of oyster mushroom against Trichoderma with the phenomena of barrage reaction, overgrowth and lysis. We also observed the inhibition of mycelial growth of oyster mushroom using the dilution method with 48-well plate, but could not observed the inhibition of mycelial growth using the filter paper method of cultural supernatant. In simultaneously culturing both Trichoderma and oyster mushroom, it was possible to detect the inhibition of the mycelial growth of oyster mushroom, but Trichoderma mycelium did not overgrow against oyster mushroom. We found that the pathogenicity was efficient in using solid medium with the phenomena of overgrowth and lysis by inoculating Trichoderma on top of mycelia of oyster mushroom. In conclusion, the methods (e.g., coculture method, dilution method with 48-well plate, post-inoculation method) are recommended to detect the resistance of oyster mushroom against Trichoderma disease.

• Journal of Mushroom
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• v.7 no.4
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• pp.193-199
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• 2009

The culture condition of unrecorded species L. aciculospora, L. boryana and L. raphanica was investigated with recorded species of L. edodes as the control group in order to analyze diversity and examed relations of the species belong to Lentinula. The optimal temperature and media for the mycelial growth of L. aciculospora and L. boryana were $22^{\circ}C$ and PDA, MCM medium. L. raphanica was $28^{\circ}C$ and ME1 medium. Each of L. aciculospora, L. boryana, L. raphanica is pH 6, pH 7, pH 5 in the optimal pH respectvely. The optimal carbon and nitrogen source of L. aciculospora were glucose and malt extract. That of L. boryana was glucose and urea that of L. raphanica was sucrose and potassium nitrate. The optimal vitamin of L. aciculospora was Myo-inositol. That of L. boryana and L. raphanica were Riboflabin.

• Korean Journal Plant Pathology
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• v.13 no.4
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• pp.200-204
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• 1997

The effect of water potential ($\psi_W$) and temperature on mycelial growth and sclerotial production of Sclerotium cepivorum was determined in potato dextrose agar(PDA) and potato dextrose broth (PDB) adjusted to different $\psi_W$ with NaCI, KCI, sucrose or polyethylene glycol (PEG) at 15, 20 and $25^{\circ}C$. the growth of mycellium was not significantly af. fected by $\psi_W$ values between -1,970 and -2,240J/Kg, but severely decreased lower than -2,240J/Kg. Dry weight was slightly increased at $\psi_W$values between -450 and -2,240 J/Kg. The reduction of dry weight wasslower than the reduction of mycelial growth as the $\psi_W$ decreased. The mycelial growth and dry weight were more severely influenced on PEG amended media than on other osmotica amended media. About 50% reduction of mycelial growth and dry weight was occurred about -1,000 and -2240 J/Kg, respectively. The production of sclerotion of sclerotial production occurred between -450 and -810 J/Kg. Sclerotium was not produced lower than -2,240 J/Kg. Mycelial growth and sclerotial production was better at $25^{\circ}C$ as the $\psi_W$ decreased than at $20^{\circ}C$ which is optimal temperaturein the undmended media. The influence of $\psi_W$ on mycelial growth and sclerotial production of S. cepivorum adjusted with NaCl, KCI sucrose or polyethylene glycol showed similar patterns.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.2
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• pp.203-209
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• 1999

This study was conducted to obtain the basic data on agricultural use of arbuscular mycorrhizal fungi(AMF) in salt accumulated plastic film house soil by evaluating the density of AMF spores in plastic film house in Yeong Nam area and surface sterility condition, germination rate of AMF spores, and hyphal growth in vitro. The density of AMF spores in plastic film house soils was highest in the site of water melon, and those of cucumber, melon, hot pepper sites were followed in order. The number of AMF was in the range of 101-207 per 100 g dry soil. With decreasing the ratio of bacteria to fungi(B/F), the population density of AMF was increased, and available $P_2O_5$ content of soil was significantly correlated to the population densities of AMF($r=0.416^*$). The surface sterility rate and spore germination of AMF isolated in plastic film house soil were more than 50% in 2% chloramin T and 2% chloramin T + antibiotic and 0.5% NaOCl treatments. The germination rate of Gigaspora margarita in the range of initial pH 5~9 of the medium was more than 56%. Hyphal growth was increased as pH of the medium increased. However the germination rate of Acaulospora spinosa was highest in the medium of pH 9, and hyphal growth in vitro was poor and not related to pH of the medium.

• Journal of Mushroom
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• v.2 no.2
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• pp.69-75
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• 2004

This study was carried out to investigate effect of $CaCO_3$ treatment on cultivation of oyster mushroom for suppression of green mold disease and for promotion of mycelial growth to stabilize mushroom production in field and laboratory experiment. Treatment of $CaCO_3$ in PDA media promoted mycelial growth of mushroom and suppressed that of green mold. Addition of $CaCO_3$ in rice straw substrate increased mushroom mycelial growth compared with control. In that case, growth of green mold increased up to treated 0.6% $CaCO_3$ but decreased in treatment beyond 0.8% $CaCO_3$. There were some differences on effect of $CaCO_3$ treatment according to green mold species. Trichoderma longibrachiatum was effected but T. virens was not effected by treated $CaCO_3$. Differences among mushroom strains by treated $CaCO_3$ were not shown. It is confirmed that treatment of $CaCO_3$ can promote mushroom mycelial growth but it's not clear in the field. In the result of field test, treatment of $CaCO_3$ in rice straw substrates tended to increase yield and decrease incidence of disease compared with non-treatment. These results suggest that $CaCO_3$ treatment on cultivation of oyster mushroom can be applied to take preventive steps against of green mold disease.