The growth rate method was adopted to measure the inhibitory effect of curcumin,tetrahydrocurcumin,demethoxycurcumin,and bisdemethoxycurcumin on the mycelial growth of Botrytis cinerea and Colletotrichum gloeosporioid...The growth rate method was adopted to measure the inhibitory effect of curcumin,tetrahydrocurcumin,demethoxycurcumin,and bisdemethoxycurcumin on the mycelial growth of Botrytis cinerea and Colletotrichum gloeosporioides.The results showed that the four curcuminoids inhibited the mycelial growth of the two pathogens in a concentration-dependent manner.Bisdemethoxycurcumin at 600 mg/L exerted the strongest inhibitory effect on the mycelial growth of B.cinerea and C.gloeosporioides,with the relative inhibition rates of 98.19%and 100%,respectively;followed by demethoxycurcumin;curcumin exerted the worst inhibitory effect.Toxicity test results also showed that four curcuminoids all had a certain toxicity to B.cinerea and C.gloeosporioides,among which,bisdemethoxycurcumin exhibited the strongest toxicity,with the EC_(50)of 131.125 and 122.235 mg/L,respectively;while curcumin had the lowest toxicity,with the EC_(50)of 273.143 and 194.943 mg/L,respectively.展开更多
For exploring the influences of application and residue of chemical fungi- cides on chlamydospore preparations of Trichoderma spp., the effects of seven chemical fungicides on chlamydospore germination and mycelia gro...For exploring the influences of application and residue of chemical fungi- cides on chlamydospore preparations of Trichoderma spp., the effects of seven chemical fungicides on chlamydospore germination and mycelia growth of two bio- control fungi T. harzianum 610 and T. Iongibrachiatum 758 were studied. Carben- dazim, tebuconazole and difenoconazole showed strong toxicities, thiram and car- bexin showed moderate toxicities, and metalaxyl showed Mycelia growth of the two strains was more sensitive to most tested fungicides than those of chlamydospore germination. Chlamydospore germination of 610 was more sensitive to tested fungicides than those of 758, and mycelia growth of 758 was more sensitive to most tested fungi- cides than those of 610. Among the seven fungicides, 98% carbendazim had the strongest effects （ECru values were 1.64 and 0.05μpg/ml）, and 70% pentachloroni- trobenzene had the weakest effects （EC50 values were 1.64 and 0,05 μg/ml） for chlamydospore germination and mycelia growth of 610. As for 758, 98% carbendaz- im had the strongest inhibitory effects and 95% metalaxyl had the weakest inhibitory for chlamydospore germination of 756 （EC50 values were 0.62 and 1 108.61 μg/ml respectively）, whereas 96.2% tebuconazole showed the strongest inhibitory effects for mycelia growth of 758 （EC= value was 0.32μg/ml）, and 95% metalaxyl was the weakest （EC= value was 1 206.29 μg/ml）. According to the applied concentration of different fungicides in practice, we concluded that chlamydospore preparations of 610 and 758 could not be combined with carbendazim, tebuconazole, thiram and carboxin for controlling plant diseases, and the pesticide residues to the biocontrol effects should be kept in mind. Chlamydospore preparations of 610 and 758 can be and difenoconazole for controlling plant dis- eases, 758 chlamydospore preparations and germinated chlamydospore of 610 can be combined with metalaxyl for controlling plant diseases, and pesticide residue risk was not serious.展开更多
The drug-containing culture medium method for the test of toxicity was adopted to compare inhibitive effects of original nano-Cu2O drug and nano-Cu2O suspension, and nano-Cu2O drug has better inhibitive effects on sna...The drug-containing culture medium method for the test of toxicity was adopted to compare inhibitive effects of original nano-Cu2O drug and nano-Cu2O suspension, and nano-Cu2O drug has better inhibitive effects on snake melon Botry- tis cinerea than original nano-Cu2O drug with the same mass concentration, and inhibitory effects are positively correlated with concentration. Correlation coefficients of the toxicity regression equation are 0.892 2 and 0.996 1, effective concentration EC50 of original nano-Cu2O drug and that of nano-Cu2O suspension are 3 948.9 and 167.9 mg/kg. Original nano-Cu2O drug has an inhibitive effect on snake melon Botrytis cinerea, but the inhibition of nano-Cu2O suspension is more obvious.展开更多
[Objective] This study was to screen out endophytic fungal strains from the bark of Juglans regia L. [Method] The bark of J. regia was washed with running water and placed on medium to let the fungi grown; the fungal ...[Objective] This study was to screen out endophytic fungal strains from the bark of Juglans regia L. [Method] The bark of J. regia was washed with running water and placed on medium to let the fungi grown; the fungal colonies were studied via morphological observation and anti-microbial activity. [Result] An endophytic fungus showing broad-scope, highly active anti-microbial activity was screened out. This fungus showed anti-microbial activity seven Gram-positive and four Gram-negative bacterial indicators, six skin pathogenic fungi and seven pathogenic fungi to different extent. Morphological observation on the ITS sequence showed that this fungus is consistent with Paecilomyces lilacinus in genus Paecilomyces bainier（with homology of over 99%）. Accordingly this fungus was designated as Paecilomyces lilacinus JY-1024. [Conclusion] This study for the first time reported the isolation of P. lilacinus from J. regia and its in vitro antimicrobial activity to several pathogens.展开更多
Thirty-six strains of marine actinomycetes were isolated from a sample of marine sediment collected from the Yellow Sea and evaluated in terms of their inhibitory activity on the growth of Aspergillus parasiticus and ...Thirty-six strains of marine actinomycetes were isolated from a sample of marine sediment collected from the Yellow Sea and evaluated in terms of their inhibitory activity on the growth of Aspergillus parasiticus and the production of norsolorinic acid using dual culture plate assay and agar diffusion methods.Among them,three strains showed strong antifungal activity and were subsequently identified as Streptomyces sp.by 16 S rRNA gene sequencing analysis.The supernatant from the fermentation of the MA01 strain was extracted sequentially with chloroform and ethyl acetate,and the activities of the extracts were determined by tip culture assay.The assay results show that both extracts inhibited mycelium growth and toxin production,and the inhibitory activities of the extracts increased as their concentrations increased.The results of this study suggest that marine actinomycetes are biologically important for the control of mycotoxins,and that these bacteria could be used as novel biopesticides against mycotoxins.展开更多
Phenazine antibiotics phenazine-l-carboxylic acid （PCA） and l-hydroxyphenazine （1-OH-PHZ） were purified from culture broth and mycelia ofStreptomyces griseoluteus P510, Both PCA and 1 -OH-PHZ exhibit strong antifu...Phenazine antibiotics phenazine-l-carboxylic acid （PCA） and l-hydroxyphenazine （1-OH-PHZ） were purified from culture broth and mycelia ofStreptomyces griseoluteus P510, Both PCA and 1 -OH-PHZ exhibit strong antifun- gal activity against six plant pathogens, especially Fusarium oxysporium, with minimal inhibition concentrations less than I and 2/ag, ml- 1 for PCA and 1-OH-PHZ, respectively, The presence of PCA and 1 -OH-PHZ indicates that S. griseoluteus PSlO can be used as a potential source of pesticides,展开更多
文摘The growth rate method was adopted to measure the inhibitory effect of curcumin,tetrahydrocurcumin,demethoxycurcumin,and bisdemethoxycurcumin on the mycelial growth of Botrytis cinerea and Colletotrichum gloeosporioides.The results showed that the four curcuminoids inhibited the mycelial growth of the two pathogens in a concentration-dependent manner.Bisdemethoxycurcumin at 600 mg/L exerted the strongest inhibitory effect on the mycelial growth of B.cinerea and C.gloeosporioides,with the relative inhibition rates of 98.19%and 100%,respectively;followed by demethoxycurcumin;curcumin exerted the worst inhibitory effect.Toxicity test results also showed that four curcuminoids all had a certain toxicity to B.cinerea and C.gloeosporioides,among which,bisdemethoxycurcumin exhibited the strongest toxicity,with the EC_(50)of 131.125 and 122.235 mg/L,respectively;while curcumin had the lowest toxicity,with the EC_(50)of 273.143 and 194.943 mg/L,respectively.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(201303057)948 Program(2011-G4)~~
文摘For exploring the influences of application and residue of chemical fungi- cides on chlamydospore preparations of Trichoderma spp., the effects of seven chemical fungicides on chlamydospore germination and mycelia growth of two bio- control fungi T. harzianum 610 and T. Iongibrachiatum 758 were studied. Carben- dazim, tebuconazole and difenoconazole showed strong toxicities, thiram and car- bexin showed moderate toxicities, and metalaxyl showed Mycelia growth of the two strains was more sensitive to most tested fungicides than those of chlamydospore germination. Chlamydospore germination of 610 was more sensitive to tested fungicides than those of 758, and mycelia growth of 758 was more sensitive to most tested fungi- cides than those of 610. Among the seven fungicides, 98% carbendazim had the strongest effects （ECru values were 1.64 and 0.05μpg/ml）, and 70% pentachloroni- trobenzene had the weakest effects （EC50 values were 1.64 and 0,05 μg/ml） for chlamydospore germination and mycelia growth of 610. As for 758, 98% carbendaz- im had the strongest inhibitory effects and 95% metalaxyl had the weakest inhibitory for chlamydospore germination of 756 （EC50 values were 0.62 and 1 108.61 μg/ml respectively）, whereas 96.2% tebuconazole showed the strongest inhibitory effects for mycelia growth of 758 （EC= value was 0.32μg/ml）, and 95% metalaxyl was the weakest （EC= value was 1 206.29 μg/ml）. According to the applied concentration of different fungicides in practice, we concluded that chlamydospore preparations of 610 and 758 could not be combined with carbendazim, tebuconazole, thiram and carboxin for controlling plant diseases, and the pesticide residues to the biocontrol effects should be kept in mind. Chlamydospore preparations of 610 and 758 can be and difenoconazole for controlling plant dis- eases, 758 chlamydospore preparations and germinated chlamydospore of 610 can be combined with metalaxyl for controlling plant diseases, and pesticide residue risk was not serious.
文摘The drug-containing culture medium method for the test of toxicity was adopted to compare inhibitive effects of original nano-Cu2O drug and nano-Cu2O suspension, and nano-Cu2O drug has better inhibitive effects on snake melon Botry- tis cinerea than original nano-Cu2O drug with the same mass concentration, and inhibitory effects are positively correlated with concentration. Correlation coefficients of the toxicity regression equation are 0.892 2 and 0.996 1, effective concentration EC50 of original nano-Cu2O drug and that of nano-Cu2O suspension are 3 948.9 and 167.9 mg/kg. Original nano-Cu2O drug has an inhibitive effect on snake melon Botrytis cinerea, but the inhibition of nano-Cu2O suspension is more obvious.
基金Supported by Science Research Fund from Yunnan Provincial Education Department(09Y0503)~~
文摘[Objective] This study was to screen out endophytic fungal strains from the bark of Juglans regia L. [Method] The bark of J. regia was washed with running water and placed on medium to let the fungi grown; the fungal colonies were studied via morphological observation and anti-microbial activity. [Result] An endophytic fungus showing broad-scope, highly active anti-microbial activity was screened out. This fungus showed anti-microbial activity seven Gram-positive and four Gram-negative bacterial indicators, six skin pathogenic fungi and seven pathogenic fungi to different extent. Morphological observation on the ITS sequence showed that this fungus is consistent with Paecilomyces lilacinus in genus Paecilomyces bainier（with homology of over 99%）. Accordingly this fungus was designated as Paecilomyces lilacinus JY-1024. [Conclusion] This study for the first time reported the isolation of P. lilacinus from J. regia and its in vitro antimicrobial activity to several pathogens.
基金Supported by the China Ocean Mineral Resources Research and Development Association Project(No.DY125-15-R-01)the National Natural Science Foundation of China(Nos.30870003,31100090)
文摘Thirty-six strains of marine actinomycetes were isolated from a sample of marine sediment collected from the Yellow Sea and evaluated in terms of their inhibitory activity on the growth of Aspergillus parasiticus and the production of norsolorinic acid using dual culture plate assay and agar diffusion methods.Among them,three strains showed strong antifungal activity and were subsequently identified as Streptomyces sp.by 16 S rRNA gene sequencing analysis.The supernatant from the fermentation of the MA01 strain was extracted sequentially with chloroform and ethyl acetate,and the activities of the extracts were determined by tip culture assay.The assay results show that both extracts inhibited mycelium growth and toxin production,and the inhibitory activities of the extracts increased as their concentrations increased.The results of this study suggest that marine actinomycetes are biologically important for the control of mycotoxins,and that these bacteria could be used as novel biopesticides against mycotoxins.
基金Supported by the National High Technology Research and Development Program of China(2012AA022107)the National Basic Research Program of China(2012CB722105)+1 种基金the National Natural Science Foundation of China(20706037)the Ph.D.Programs Foundation of Ministry of Education of China(20090073110052)
文摘Phenazine antibiotics phenazine-l-carboxylic acid （PCA） and l-hydroxyphenazine （1-OH-PHZ） were purified from culture broth and mycelia ofStreptomyces griseoluteus P510, Both PCA and 1 -OH-PHZ exhibit strong antifun- gal activity against six plant pathogens, especially Fusarium oxysporium, with minimal inhibition concentrations less than I and 2/ag, ml- 1 for PCA and 1-OH-PHZ, respectively, The presence of PCA and 1 -OH-PHZ indicates that S. griseoluteus PSlO can be used as a potential source of pesticides,
