Factors of influence on conidium germination and appressorium formation of Setosphaeria turcica,such as light condition,conidial concentration,nutrient resources and pH value of conidial suspension were studied.There ...Factors of influence on conidium germination and appressorium formation of Setosphaeria turcica,such as light condition,conidial concentration,nutrient resources and pH value of conidial suspension were studied.There was no significant difference among light treatments.The optimal pH for conidium germination and appressorium formation was 5.0 to 7.0.The exogenous nutrient sources were not the indispensable factors for conidium germination,but 5% sugar solution were more favorable for appressorium formation than the others.Low conidial concentration in suspension(conidia ≤104/mL)was propitious to conidium germination and appressorium formation,which were inhibited significantly in higher concentration.It was suggested that the phenomenon was due to the self-inhibitor,a kind of lipophilic substance,existing in the site of conidium germination.展开更多
The EC50 values of matrine and oxymatrine against five forest pathogenic fungi （Fusarium oxysporum, Valsa pini, Cladosporium oxysporum, Sphaeropsis sapinea, Marssonina brunnea） were examined by bioassay methods. The...The EC50 values of matrine and oxymatrine against five forest pathogenic fungi （Fusarium oxysporum, Valsa pini, Cladosporium oxysporum, Sphaeropsis sapinea, Marssonina brunnea） were examined by bioassay methods. The results demonstrated that matrine and oxymatrine had strong inhibitory activities to the conidium germination of the tested fungi. The ECso values of matrine for inhibiting the conidium germination of Marssonina brunnea, Cladosporium oxysporum, Sphaeropsis sapinea were 123μg·mL^-1, 272 μg·mL^-1, 1133 μg·mL^-1, respectively, and the EC50 values of oxymatrine for inhibiting the conidium germination of Fusarium oxysporum, Sphaeropsis sapinea were 532μg·mL^-1, 601μg·mL^-1, respectively. The hyphal growth of the fungi was also significantly inhibited by matrine and oxymatrine. The ECs0 values of matrine inhibiting the conidium germination of Sphaeropsis sapinea, Valsa pini, Fusarium oxysporum were 428μg·mL^-1, 535 μg·mL^-1, 592 μg·mL^-1, respectively. The EC50 values of oxymatrine inhibiting the conidium germination of Valsa pini, Fusarium oxysporum were 323, 618μg·mL^-1, respectively. In the synergetic tests the ECs0 values of the mixtures of thiophanate methyl （or chlorthalonil） and matrine （or oxymatrine） were lower than 34 μg·mL^-1 while their co-toxicity coefficients were significantly higher than 1130 It indicated that the mixture of the alkaloids and the chemical had potential practical utilization in controlling certain forest fungal diseases.展开更多
文摘Factors of influence on conidium germination and appressorium formation of Setosphaeria turcica,such as light condition,conidial concentration,nutrient resources and pH value of conidial suspension were studied.There was no significant difference among light treatments.The optimal pH for conidium germination and appressorium formation was 5.0 to 7.0.The exogenous nutrient sources were not the indispensable factors for conidium germination,but 5% sugar solution were more favorable for appressorium formation than the others.Low conidial concentration in suspension(conidia ≤104/mL)was propitious to conidium germination and appressorium formation,which were inhibited significantly in higher concentration.It was suggested that the phenomenon was due to the self-inhibitor,a kind of lipophilic substance,existing in the site of conidium germination.
基金This work was supported by a project of NationalNatural Science Foundation of China (No. 30170776)
文摘The EC50 values of matrine and oxymatrine against five forest pathogenic fungi （Fusarium oxysporum, Valsa pini, Cladosporium oxysporum, Sphaeropsis sapinea, Marssonina brunnea） were examined by bioassay methods. The results demonstrated that matrine and oxymatrine had strong inhibitory activities to the conidium germination of the tested fungi. The ECso values of matrine for inhibiting the conidium germination of Marssonina brunnea, Cladosporium oxysporum, Sphaeropsis sapinea were 123μg·mL^-1, 272 μg·mL^-1, 1133 μg·mL^-1, respectively, and the EC50 values of oxymatrine for inhibiting the conidium germination of Fusarium oxysporum, Sphaeropsis sapinea were 532μg·mL^-1, 601μg·mL^-1, respectively. The hyphal growth of the fungi was also significantly inhibited by matrine and oxymatrine. The ECs0 values of matrine inhibiting the conidium germination of Sphaeropsis sapinea, Valsa pini, Fusarium oxysporum were 428μg·mL^-1, 535 μg·mL^-1, 592 μg·mL^-1, respectively. The EC50 values of oxymatrine inhibiting the conidium germination of Valsa pini, Fusarium oxysporum were 323, 618μg·mL^-1, respectively. In the synergetic tests the ECs0 values of the mixtures of thiophanate methyl （or chlorthalonil） and matrine （or oxymatrine） were lower than 34 μg·mL^-1 while their co-toxicity coefficients were significantly higher than 1130 It indicated that the mixture of the alkaloids and the chemical had potential practical utilization in controlling certain forest fungal diseases.
