• 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.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.53-59
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• 1996

This study was conducted to evaluate the effects of fowl dzopping. saw dust and rice hall on the soil microflora in vitro. The experiment was designed in seven treatments with the various organic materials and they were only soil (control). soil + fowl dropping (S+F), soil+fowl dropping+rice hull (S+F+R) soil+fowl dropping*saw dust (S+F+S). soil+chemical fertilizer (S+C.F), fowl dropping+rice hull (F+R) and fowl dropping+saw dust (F+S). All the samples of treatment were incubated in $28{\pm}2^{\circ}C$ condition and tested the activity of soil microflora for 84 days The activity of fungi, total bacteria, gram-negative bacteria and actinomycetes showed the highest values at, twenty-first day and the spore-forming bacteria was at forty-second day after incubation. The number of fungi and gram-negative bacteria showed the highest values in the treatment of F+S, the spore-forming bacteria and the actinomycetes were in the S+F+S. and the number of total bacteria was in the F+C.F., but in the treatment of F+R. all the microorganism except fungi showed the lowest values in their numbers. The composition ratio of dead bacteria was higher in the treatments of S+F+R and F+R than in those of others as 70% and 40% respectively. Actinomycetes isolated from the treatments of S+F and S+F+S were identified as Streptomyces sp.. Nocardia sp., Micromonospora sp. Actinomadura sp. and Saccharomonospora sp.

• Applied Biological Chemistry
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• v.34 no.1
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• pp.54-60
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• 1991

Serratia marcescens CK-3, decomposing chitin which is a mar component of cell wall in phyitopathogenic fungi, was isolated from the continuous cropping rhizosphere of pepper and cucumber and its enzymatic property was examined. S. marcescens CK-3 was found tn have an tagonistic effects against, Fusarium axysporum and Rhizoctonia solani and to have complex enzyme system such as chitinase, laminarinase, and proteinase. The preferable composition of the medium for production of chitinase was fond and was as follows : colloidal chitin 1.5%, tryptone 0.5%, glucose 1.0%, peptone 0.2%, $MgSO_4{\cdot}7H_2O\;0.1%,\;K_2HPO_4\;0.1%,\;and\;NaCl\;0.1%$(w/v), pH 6.8. The maximum enzyme production was observed after culture of 72 hours at $30^{\circ}C$ using a medium containing the above chemical composition. The optimal pH and temperature for in vitro activity of chitinase from S. marcescens CK-3 were pH 7.5 and $50^{\circ}C$, respectively. The enzyme activity in-creased by metal ions such as$Ag^+$ and $Mn^{++}$.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.194-199
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• 2010

Compost as a soil amendment is of importance in enhancing the soil chemical and microbial qualities; however, soil microbial community can vary depending on the composition, and the amount of compost applied to plant in the soil. Responses of soil microbial properties to compost applications with 0, 30, and 60 Mg $ha^{-1}$ were investigated in silt loam soils where red pepper(Capsicum annuum L.) was mainly cultivated in Yeongyang, Gyeongbuk, Korea. The analysis of phospholipid fatty acids (PLFAs) extracted from soil showed that compost amounts significantly increased PLFAs representing as bacteria, fungi, and VAM-fungi as well as the ratio of fungi/bacteria, and monounsaturated/saturated PLFAs. Increasing the amount of compost significantly increased Gram-/Gram+ PLFAs' ratio, but significantly decreased monounsaturated/saturated PLFAs' ratio. Therefore, this result shows that compost would vary to a limited extent the microbial community in red pepper field. However, increase in compost application would change the subgroup structure of microbial community only.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.4
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• pp.302-309
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• 2000

These experiments have been conducted to study the effect by microbial inoculums currently on the market of enhancing the decomposition of organic matters. As a result of studying the effect of enhancing the decomposition of rice straw and chicken manure mixed with saw dust treated with commercial inoculums, it was found that the use of inoculums have speeded up the rate of decomposing straws at the early stage. The decomposition rate of rice straws that have speeded up with the use of comcrial inoculums in at early incubation periods has slow down in the later stage while the decomposition rate of chicken manure that has slowed down in the early stage has speeded up at the later incubation. As a result, it is found that there have been no differences between the use of microbial inoculums and control. In the experiment, filamentous fungus is found to have played an important role in decomposing the rice straws and bacteria is considered to have played a greater role in the decomposition of chicken manure mixed with saw dust.

• The Korean Journal of Mycology
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• v.46 no.4
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• pp.511-518
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• 2018

Initiation of spore germination in filamentous fungi such as Aspergillus nidulans and Botrytis cinerea requires the presence of nutrients. In this study, involvement of sugar sensing machinery was suggested in the germination of A. nidulans spores. Germination did not occur when the spores of A. nidulans were incubated in distilled water, whereas they were successfully germinated in the presence of 5% glucose with a germination rate of over 98% after 6hr incubation. Similar results were obtained when the spores were incubated in the presence of various sugars such as fructose, sucrose, and starch. Interestingly, spore germination was not observed in the presence of D-arabinose, whereas L-arabinose could induce germination as determined by the formation of germ tubes, indicating the presence of sugar sensing machinery that distinguish between the enantiomers of sugars. This inference was further supported by a decrease in germination rate (less than 25%) upon treatment of spores with trypsin. Subsequent MALDI-TOF mass spectrometry analysis of the surface proteins of spores identified ten proteins among which eight were involved in sugar metabolism. Taken together, our results suggest that spore germination in A. nidulans is initiated by the interaction of sugars with sugar binding proteins on the surface of spores.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.3
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• pp.299-306
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• 1984

The influences of applications of organochlorine insecticide (HCH: Hexachlorocyclohexane, 10 ppm), fungicide (TPN: Tetrachloroisophthalonitrile, 40 ppm) and manure ($3Kg/m^2$) each or together on changes in soil microflora for consecutive years were investigated in the experimental field plots. The insecticide had a little effect on soil microbial numbers. In particular, the number of total bacteria, Gram-negative bacteria and fungi were gradually increased at the latter stage of the consecutive application, but the number of sporeforming bacteria reduced. The fungicide reduced the counts of sporeforming bacteria, actinomycetes and fungi respectively, whereas increased prominently the counts of total bacteria and Gram-negative bacteria. TPN-resistant bacteria, particulary TPN-resistant Gram-negative bacteria were gradually accumulated by the long-term application of TPN, and further the number of TPN-resistant total bacteria and the of TPN-resistant Gram-negative bacteria correlated fairly well during all the period. The influences of combined applications of both HCH and TPN on the number of soil microorganisms were equal to the respective sums of the effects of single application of each pesticide. The combined application of manure and these pesticides elevated the increasing extents of microbial numbers, while weakened the detrimental efforts of these pesticides on microbial numbers. These data suggest that the long-term application of these materials have resulted in the remarkable changes of composition of soil microflora.

• Agrochemical news magazine
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• v.19 no.1 s.142
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• pp.54-57
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• 1998

• Microbiology and Biotechnology Letters
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• v.8 no.1
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• pp.47-53
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• 1980

For the Purpose of studies on the citric acid fermentation, 579 strains of Aspergilli were isolated from natural sources of microorganisms. Out of them, the strains of M-80 and M-315 which produced relatively larger amount of citric acid than any others were selected after calling out an extensive screening test. The results obtained in light of the manual of Raper had been shown that the selected strains of M-80 and M-315 were identified as Aspergillus usamii mut. shirousamii, Aspergillus ficuum, respectively.

• Korean Journal of Microbiology
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• v.18 no.2
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• pp.91-103
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• 1980

A mycological survey was carried out with the soil samples collected in Korea from Sptember, 1978 to December, 1979. Special attention was paid fungus genus Penicillum. One hundred twenty three isolates, as a result, were obtained from the Korean soils. Among these, sixteen species were iedentified and described in this paper. Almost all of the fungi reported here are new to Korea. One of them is an asomycete cleisothecia of $120~50\mu$ in diameter. Ascospores of this fungus were found lenticular with an equatorial furrow as indicated in the previous descriptions.