28 soil samples were collected from the rhizosphere of 16 plant species in six different districts in Hunan. As a result of isolation and purification, 122 fungus strains were obtained of which the antagonistic activi...28 soil samples were collected from the rhizosphere of 16 plant species in six different districts in Hunan. As a result of isolation and purification, 122 fungus strains were obtained of which the antagonistic activity was tested against six fungus pathogens in tomato, cotton, cucumber, chilli, rice and rape, and 17 strains were found antagonistic to one or more pathogenic fungi.展开更多
Objective:Fusarium oxysporum is a common pathogenic fungus in ginseng cultivation.Both pathogens and antagonistic fungi have been reported to induce plant resistance responses,thereby promoting the accumulation of sec...Objective:Fusarium oxysporum is a common pathogenic fungus in ginseng cultivation.Both pathogens and antagonistic fungi have been reported to induce plant resistance responses,thereby promoting the accumulation of secondary metabolites.The purpose of this experiment is to compare the advantages of one of the two fungi,in order to screen out more effective elicitors.The mechanism of fungal elicitor-induced plant resistance response is supplemented.Methods:A gradient dilution and the dural culture were carried out to screen strains.The test strain was identified by morphology and 18 s rDNA.The effect of different concentrations(0,50,100,200,400 mg/L)ofPenicillium sp.YJM-2013 and F.oxysporum on fresh weight and ginsenosides accumulation were tested.Signal molecules transduction,expression of transcription factors and functional genes were investigated to study the induction mechanism of fungal elicitors.Results:Antagonistic fungi ofF.oxysporum was identified as Penicillium sp.YJM-2013,which reduced root biomass.The total ginsenosides content of Panax ginseng adventitious roots reached the maximum(48.95±0.97 mg/g)treated with Penicillium sp.YJM-2013 at 200 mg/L,higher than control by 2.59-fold,in which protopanoxadiol-type ginsenosides(PPD)were increased by 4.57 times.Moreover,Penicillium sp.YJM-2013 activated defense signaling molecules,up-regulated the expression of PgWRKY 1,2,3,5,7,9 and functional genes in ginsenosides synthesis.Conclusion:Compared with the pathogenic fungi F.oxysporum,antagonistic fungi Penicillium sp.YJM-2013 was more conducive to the accumulation of ginsenosides in P.ginseng adventitious roots.Penicillium sp.YJM-2013 promoted the accumulation of ginsenosides by intensifying the generation of signal molecules,activating the expression of transcription factors and functional genes.展开更多
文摘28 soil samples were collected from the rhizosphere of 16 plant species in six different districts in Hunan. As a result of isolation and purification, 122 fungus strains were obtained of which the antagonistic activity was tested against six fungus pathogens in tomato, cotton, cucumber, chilli, rice and rape, and 17 strains were found antagonistic to one or more pathogenic fungi.
基金The work was supported by National Natural Science Foundation of China NSFC(No.81703639).
文摘Objective:Fusarium oxysporum is a common pathogenic fungus in ginseng cultivation.Both pathogens and antagonistic fungi have been reported to induce plant resistance responses,thereby promoting the accumulation of secondary metabolites.The purpose of this experiment is to compare the advantages of one of the two fungi,in order to screen out more effective elicitors.The mechanism of fungal elicitor-induced plant resistance response is supplemented.Methods:A gradient dilution and the dural culture were carried out to screen strains.The test strain was identified by morphology and 18 s rDNA.The effect of different concentrations(0,50,100,200,400 mg/L)ofPenicillium sp.YJM-2013 and F.oxysporum on fresh weight and ginsenosides accumulation were tested.Signal molecules transduction,expression of transcription factors and functional genes were investigated to study the induction mechanism of fungal elicitors.Results:Antagonistic fungi ofF.oxysporum was identified as Penicillium sp.YJM-2013,which reduced root biomass.The total ginsenosides content of Panax ginseng adventitious roots reached the maximum(48.95±0.97 mg/g)treated with Penicillium sp.YJM-2013 at 200 mg/L,higher than control by 2.59-fold,in which protopanoxadiol-type ginsenosides(PPD)were increased by 4.57 times.Moreover,Penicillium sp.YJM-2013 activated defense signaling molecules,up-regulated the expression of PgWRKY 1,2,3,5,7,9 and functional genes in ginsenosides synthesis.Conclusion:Compared with the pathogenic fungi F.oxysporum,antagonistic fungi Penicillium sp.YJM-2013 was more conducive to the accumulation of ginsenosides in P.ginseng adventitious roots.Penicillium sp.YJM-2013 promoted the accumulation of ginsenosides by intensifying the generation of signal molecules,activating the expression of transcription factors and functional genes.
