• KSBB Journal
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• v.10 no.2
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• pp.166-169
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• 1995

Spores of Trichoderma harzianum TCC 52445 for control of Rhlzocronia stem canker on potato were immobilized in various natural matrix, and germination rate and some rheological properties of the spore-matrix complex were Investigated. Germination rate of gelatin gel-spore complex and potato starch gel-spore complex were 2.8% and 2.9%, respectively, but hardness and cohesiveness of the gelstin gel-spoke complex were better than those of potato starch-spore complex. The hardness and cohesiveness were increased when the spores were immobilized in hybrid gelatin gel made by mixing several different types of natural matrix, but decreased their germination rate. Addition of corn steep liquor (1%) as spore nutrient in gelatin gel-spore complex was helpful for increasing the germination rate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.1
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• pp.37-43
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• 1983

The effects of pH, sodium chloride and potassium sorbate on the germination of Bacillus cereus spores in the medium of cooked rice homogenate were studied. At the range of pH $4.5{\sim}10.0$, the germination of spores were observed. Germinated spores were reached to the number of $10^7/ml$ within 5 hours at $32^{\circ}C$ under the condition of pH 7.0, which was found as optimum pH of germination. In the range of sodium chloride $2{\sim}10\%$, the maximum growth were exhibited under $2\%$ concentration, while it proportionally decreased under the salinity condition higher than $5\%$. The growth of Bacillus cereus were inversely related to the concentration of potassium sorbate within the range of $0{\sim}0.2\%$. Maximum sporulation ratio was observed under the culturing condition: $10\%$ NaCl and $0.2\%$ potassium sorbate in the medium of cooked rice homogenate.

• The Korean Journal of Mycology
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• v.15 no.4
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• pp.254-259
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• 1987

This study was carried out to investigate the germination of four fungi under non-leaching and leaching incubation. The range of germination rates of Fusarium solani f. sp. pisi, Fusarium oxysporum f. sp. cucumerium, Mortierella, and Helminthosporium sativa incubated on sand saturated with various solutions without leaching were 90-99%, 31-45%, 38-62% and 86-98% respectively. The range of germination rates of Fusarium solani f. sp. pisi, Fusarium oxysporum f. sp. cucumerium, Mortierella n. sp and Helminthosporum sativa incubated on sand undergoing leaching were 51-63%, 13-25%, 15-37% and 47-80%, respectively. The germination rates of the four fungi tested were suppressed under leaching incubation.

• Research in Plant Disease
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• v.17 no.3
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• pp.381-385
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• 2011

Effects of temperatures, relative humidity, pH, and dry periods on conidial germination of Alternaria dauci were evaluated under in vitro conditions. Conidial germination was accelerated at over 95% relative humidity in $15^{\circ}C$ to $25^{\circ}C$ condition. Conidial germination was rapidly reduced at 5 regardless of relative humidity conditions. More than 50% of the conidial germination were initiated within 2 h at $25^{\circ}C$ through pH 5 to 7. The highest conidial germination of A. dauci was on 0.2% of carrot leaf extract. Conidia could survive longer than 12 h, even though its germination decreased. After a 12 h dry period, around 10% of conidia revived and germinated when conidia were hydrated again. These results could be used as the useful information on conidial germination of A. dauci and ecology of Alternaria leaf blight.

• The Korean Journal of Pesticide Science
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• v.4 no.4
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• pp.66-71
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• 2000

Effect of temperature on resting spore germination of Plasmodioprora brassicae was indirectly estimated based on examining temporal change of number of inactive resting spores. Resting spore germination was the highest at $28^{\circ}C$ reaching 55.6% and 82.5%, 24hr and 132hr after treatment, respectively. Optimum pH for resting spore germination was pH6, following pH7 and pH8, and the germination was inhibited at pH 4, and pH9. termination of resting spores was stimulated by root extracts of radish, Chinese cabbage and kidney bean, but inhibited by that of lettuce. Number of inactive resting spores was increased as temperature increases and time prolongs after temperature treatment. However, degree of inactivation of resting spores after 1hr at $40{\sim}65^{\circ}C$ was similar with $40{\sim}60%$, but rapidly increased to 91.5% at $70^{\circ}C$. When root galls were submerged in water, density of inactive resting spores was increased rapidly and reached 60.3% 9 days after treatment. Flooding of infested soil resulted in 30% reduction of survived resting spores 5 months later. Among the two registered fungicides, fluazinam was better for inactivation of resting spores than flusulfamide, but both fungicides were inferior to phosphoric acid.

• Korean Journal Plant Pathology
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• v.13 no.4
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• pp.210-214
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• 1997

The experiment was conducted to obtain basic informations on the effects of key environments and fungicides on the sporulation, conidial germination and hitial growth of the hyphae of grape powdery mildew fungus Uncinula necator. Maximum sporulation occurred at RH 75~96% in vitro adiusted with sulfuric acid solution. Conidial germination and initial growth of the hyphae were better at 5% water agar than distilled water, and best at $26^{\circ}C$ and pH 5.0 of the substrates. Germination occurred equally well at light intensity of below 100 lux or dark condition, which was better at water agar supplemented with leaf extract 30% than pure water agar. The water agar supplemented with triazole fungicides reduced conidial germinations and initial growth of the hyphae signifcantly, in proportion to the increase in concentration of the fungicides, but the maguitude of reduction depended on the fungicides. Particularly in myclobutanil, reduction rate was very low as increased in concentration.

• 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.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2001.12a
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• pp.87-87
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• 2001

• Proceedings of the Zoological Society Korea Conference
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• 2001.10a
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• pp.148.4-149
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• 2001

• The Korean Journal of Mycology
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• v.12 no.3
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• pp.99-103
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• 1984

Hyphal growth by Fusarium moniliforme was best at -14 bars osmotic water potential. Hyphal growth was prevented at -94 bars. The production of microconidia was best at -14 bars osmotic potential and prevented at -84 bars regardless of Strain. In contrast, this fungus sporulated macroconidia best at -1.4 bars and progressively less with each increment drop in water potential below that of basal media. The rate of spore germination followed a similar pattern with all of the spores; uniformly maximal at about -1.4 bars and progressively slower as the water potential was lowered from -1.4 bars to -42 bars. Under the natural conditions, plants infected by F. moniliforme produce microconidia on the dead tissues instead of producing macroconidia. This phenomenon agrees well with the water potential experiment since the dead plant tissues have a lower water potential than the living plant.