• Korean Journal of Agricultural Science
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• v.17 no.2
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• pp.77-81
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• 1990

Effects of buprofezin, an inhibitor of chitin synthesis, on mycelial growth, protoplast formation and reversion of Pleurotus ostreatus and P. sajor-caju were investigated. The mycelial growth of Pleurotus ostreatus and P. sajor-caju was the inhibited by buprofezin treatment, and the inhibition rate was severer as the concentration of the buprofezin increased. Aerial mycelium formation was increased by buprofezin treatment, but mycelial morphology was not changed. Protoplast formation of Pleurotus ostreatus and P. sajor-caju. was significantly increased when buprofezin was added to the culture medium at the concentration of 200~500 ppm and the protoplast reversion of the mushrooms was also increased by the treatment of the buprofezin.

• Mycobiology
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• v.47 no.4
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• pp.506-511
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• 2019

We investigated the antifungal activities of an endophytic fungus identified as Acaromyces ingoldii, found on a loblolly (Pinus taeda L.) pine bolt in Louisiana during routine laboratory microbial isolations. The specific objectives were to determine the inhibitory properties of A. ingoldii secondary metabolites (crude extract) on the mycelial growth of a brown-rot fungus Gloeophyllum trabeum and a white-rot fungus Trametes versicolor, and to determine the effective concentration of A. ingoldii crude preparation against the two decay fungi in vitro. Results show the crude preparation of A. ingoldii from liquid culture possesses significant mycelial growth inhibitory properties that are concentration dependent against the brownrot and white-rot fungi evaluated. An increase in the concentration of A. ingoldii secondary metabolites significantly decreased the mycelial growth of both wood decay fungi. G. trabeum was more sensitive to the inhibitory effect of the secondary metabolites than T. versicolor. Identification of specific A. ingoldii secondary metabolites, and analysis of their efficacy/specificity warrants further study. Findings from this work may provide the first indication of useful roles for Acaromyces species in a forest environment, and perhaps a future potential in the development of biocontrol-based wood preservation systems.

• Mycobiology
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• v.35 no.2
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• pp.76-81
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• 2007

Lactobacillus casei KC-324 was tested for its ability to inhibit aflatoxin production and mycelial growth of Aspergillus flavus ATCC 15517 in liquid culture. flatoxin $B_{1}$ biosynthesis and mycelial growth were inhibited in both simultaneous culture and individual antagonism assays, suggesting that the inhibitory activity was due to extracellular metabolites. produced in cell-free supernatant fluids of the cultured broth of L. casei KC-324. In cell-free supernatant fluids of all media tested, deMan, Rogosa and Sharpe broth, potato dextrose broth, and Czapek-Dox broth+1% yeast extract showed higher antiaflatoxigenic activity. In these case, fungal growths, however, was not affected as measured by mycelial dry weight. The antiaflatoxigenic metabolites from L. casei KC-324 were produced over wide range of temperatures between $25^{\circ}C$ and $37^{\circ}C$. However, these metabolites were not thermostable since the inhibitory activity of the supernatant was inactivated within 30 minutes at $100^{\circ}C$ and $121^{\circ}C$. The inhibitory activity was not influenced by changing pH of supernatant between 4 and 10. However, the antiaflatoxigenic activity was slightly reduced at pH 10.

• Mycobiology
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• v.37 no.4
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• pp.277-285
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• 2009

In this study, dual culture, poison agar, and direct methods were used to assess the ability of Trichoderma virens IMI-392430, T. pseudokoningii IMI-392431, T. harzianum IMI-392432, T. harzianum IMI-392433, and T. harzianum IMI-392434 to control Ceratocystis paradoxa, which causes the pineapple disease of sugarcane. The highest percentage inhibition of radial growth (PIRG) values were observed with T. harzianum IMI-392432 using two dual culture methods, 63.80% in Method I and 80.82% in Method II. The minimum colony overgrowth time was observed with T. harzianum IMI-392432 and the maximum was observed with T. pseudokoningii IMI-392431. Different concentrations of different day-old metabolites of Trichoderma isolates were tested against mycelial growth of C. paradoxa. The highest PIRG (84.685%) exhibited at 80% concentration of 30-day-old metabolites of T. harzianum IMI-392432 using the modified bilayer poison agar method. In the direct assay method the maximum mycelial growth weight (PIGW) was observed at the same concentration and the same day-old metabolites of T. harzianum IMI-392432. This study showed that Trichoderma isolates have a good antagonistic effect on C. paradoxa mycelial growth and T. harzianum IMI-392432 has the most potential to control the pineapple disease pathogen.

• Mycobiology
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• v.28 no.4
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• pp.190-192
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• 2000

Antifungal bacteria for biological control of plant diseases or production of novel antibiotics to plant pathogens were isolated in 1997 from various soils of Ansung, Chunan, Koyang, and Paju in Korea. Sixty-four bacterial strains pre-screened from approximately 1,400 strains were tested on V-8 juice agar against eight plant pathogenic fungi using in vitro bioassay technique for inhibition of mycelial growth. Test pathogens were Alternaria mali, Colletotrichum gloeosporioides, C. orbiculare, Fusarium oxysporum f. sp. cucumerinum, F. oxysporum f. sp. lycopersici, Magnaporthe grisea, Phytophthora capsici, and Rhizoctonia solani. A wide range of antifungal activity of bacterial strains was found against the pathogenic fungi, and strain RC-B77 showed the best antifungal activity. Correlation analysis between inhibition of each fungus and mean inhibition of all eight fungi by 64 bacterial strains revealed that C. gloeosporioides would be best appropriate for detecting bacterial strains producing antibiotics with potential as biocontrol agents for plant pathogens.

• Journal of Microbiology and Biotechnology
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• v.5 no.6
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• pp.341-345
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• 1995

Seventy four microorganisms, which have antagonistic activity against to Fusarium culmorum, were tested for their inhibitory effect on colony development of obligate biotroph Erysiphe graminis f. sp. hordei Marchal, the causal agent of powdery mildew on barley plants. Of these, 13 actinomycetes isolates were shown to reduce the colony development of mildew completely by application of their 10% cell-free culture filtrates on barley leaves. An Isolate, A252, was the most powerful antagonist and its antifungal activity was further assessed. The colony development of mildew was significantly reduced by application of the 1% cell-free culture filtrate of isolate A252. In comparison to the control, the protective and curative application of 10% cell-free culture filtrate from A252 showed 88.5% and 96.1% reduction of colony numbers respectively. By the protective application, 68.3% of the inhibition was observed after 9 days of treatment, thus showed prolonged inhibitory effect. In vitro test, complete inhibition of the mycelial growth of Microdochium nivale was achieved by the treatment of 1% A252 culture filtrate and 80.2% of inhibition was observed by the 0.1% treatment.

• Journal of Mushroom
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• v.11 no.1
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• pp.24-31
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• 2013

As a result of advenced research, Penicillium growth inhibition effect in media of cauliflower mushroom by different LED lighting color inhibited all treated groups, but blue wavelength treatment group was unfitted for culture of cauliflower mushroom due to lots of spore of penicillium. So, to investigated characteristics of mycelial growth of cauliflower mushroom according to different LED wavelength and LED wavelength color. As a results, all red wavelength treatment groups found highest mycelial growth tendency. Thus, mycelial growth investigated different quantity of red lighting wavelength conditions. The quantity of lighting wavelength was low intention, 1.41 ${\mu}mol/m^2S$ treatment group found highest mycelial growth. Effects of mycelial growth by subculture found difference of statistical in one time to carry out a subculture treatment group. Mycelial growth by different quantity of LED lighting in different media composition of wood chip media indicated highest trend in the Korean pine treatment groups. To cultured treatment group for 84th days found difference of statistical, when a quantity of LED lighting red wavelength 2.11 ${\mu}mol/m^2S$ treated in wood chip of the Korean pine media. In conclusion, good culture condition of cauliflower mushroom estimated quantity of red lighting wavelength 2.11 ${\mu}mol/m^2S$ in wood chip media of the Korean pine for 84th days.

• The Plant Pathology Journal
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• v.36 no.2
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• pp.133-147
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• 2020

Hexanal, a C-6 aldehyde has been implicated to have antimicrobial properties. Hence, this study was conducted to determine the antifungal activities of hexanal vapor against major postharvest pathogens of banana viz., Colletotrichum gloeosporioides and Lasiodiplodia theobromae. The pathogens were cultured in vitro and exposed to hexanal vapor at 600, 800, 1,000 and 1,200 ppm. Mycelial growth of both fungal pathogens were inhibited completely at 800 ppm and the incidence of anthracnose and stem-end rot diseases reduced by 75.2% and 80.2%, respectively. The activities of peroxidase, polyphenol oxidase, phenylalanine ammonia-lyase and glucanase had transiently increased in hexanal vapor treated banana by 5 to 7 days and declined thereafter. Postharvest treatment of banana with hexanal vapor resulted in phospholipase D inhibition and also resulted in cell wall thickening of the treated fruit, which impeded the penetration of the pathogenic spores. This was further confirmed by scanning electron micrographs. The defense-related protein intermediaries had increased in hexanal vapor treated banana fruit, which suggests induced resistance against C. gloeosporioides and L. theobromae, via., the phenylpropanoid pathway which plays a significant role in hindering the pathogen quiescence. Delayed ripening due to inhibition of phospholipase D enzyme, inhibition of mycelial growth and induced systemic resistance by defense enzymes collectively contributed to the postharvest disease reduction and extended shelf life of fruit.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.271.2-271.2
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• 2003

The ${\gamma}$- and ${\beta}$-secretase are one of the most important proteases, which cleave amyloid precursor protein (APP) into neurotoxic A${\beta}$ peptide in Azheimer's type dementia. In the course of screening for anti-dementia agents from natural products, the mycelial culture of mushroom Phellinus linteus showed potent inhibition againt ${\beta}$-secretase (BACE1). (omitted)

• Korean Journal of Environmental Agriculture
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• v.37 no.1
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• pp.34-40
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• 2018

BACKGROUND: In order to select a fungicide that can effectively control anthracnose disease in Japanese plum fruit, mycelial growth inhibition effect and spore germination inhibition effect of six fungicides were tested in vitro against six isolates of Colletotrichum acutatum and five isolates of C. gloeosporioides that were isolated from diseased Japanese plum fruit. METHODS AND RESULTS: Inhibitory effects of fungicides on mycelial growth were investigated after inoculating each isolate on potato dextrose agar amended with four discriminatory concentrations of each fungicide for 7 days at $25^{\circ}C$. For spore germination inhibitory effect, each isolate of the Colletotrichum spp. was cultured in potato dextrose agar for 7-14 days at $25^{\circ}C$. After adjusting the concentration of spores of each isolate to $1{\times}10^6mL^{-1}$ by diluting with 0.025% PDB, the spore suspension was mixed with each fungicide (1:4, v/v), and $60{\mu}L$ aliquots were dispensed to sterile hole slide glass. Hole slide glasses were placed in a humidified box and incubated for 15 hours at $25^{\circ}C$. Then, spore germination was observed under an optical microscope. At recommended concentration of fungicide prochloraz manganese showed the highest mycelial growth inhibitory effect and dithianon showed the lowest mycelial growth inhibition. The $EC_{50}$ values for the inhibition of spore germination by dithianon and pyraclostrobin were $0.069-0.126{\mu}g/mL$ and $0.37-1.59{\mu}g/mL$, respectively. Although benomyl, prochloraz manganese, azoxystrobin, and tebuconazole did not inhibit the spore germination, they appeared to restrain mycelial growth by abnormal growth of germ tube and mycelium after germination. CONCLUSION: Dithianon seemed to have preventive effect. Prochloraz manganese, azoxystrobin, and tebuconazole were likely to have control effect. Pyraclostrobin is considered to have both preventive and control effect against anthracnose disease of Japanese plum fruit.