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Endophytic fungus (endophytic fungi) is the survival of the healthy plant roots, stems, leaves, fruit internal formation of pathological infringement or has not yet formed a class of fungi obvious infection of the host plant . Plants and their endogenous fungal mutualism , plant endophytic fungi survive the photosynthetic products and essential minerals , that the endogenous fungal secondary metabolites directly stimulate or indirectly conducive to plant growth and development , thus improving the host plant to biotic stress and abiotic the stress of the stress resistance . Rosaceae Pyracantha stem , leaf , fruit isolated 15 endophytic fungi , isolated stem 4 (S1-S4), leaves 8 ( L1 -L8 ) , fruit 3 (F1- F3); nine species common disease pathogens ( tobacco brown spot , apple anthracnose fungus , fusarium head blight bacteria ) as the target bacteria , antibacterial activity detection Pyracantha endogenous fungal secondary metabolites , obtained with higher suppression bacterial activity within endophytic fungi S4 . 15 endophytic fungi as test material after liquid shaker culture , the total culture fermentation broth and mycelium dry grinding with acetone extraction , determination of the total culture acetone crude extracts of nine plant pathogenic fungi antibacterial activity and virulence equations , qualitative detection of the chemical composition of the liquid culture of S4 . The results showed that the 15 endophytic fungi , antibacterial activity strains accounted for 86.67% . The S4 strain liquid cultures acetone extract of nine kinds of pathogenic fungi tested showed significant antibacterial activity , antibacterial rate of 50 % , up 97.14%, and the broader antibacterial spectrum ; strains S1, S3 , L1 acetone crude extract had higher inhibition rate . Experiments show that the chemical composition of the S4 metabolites may contain reducing sugars, organic acids , flavonoids , lactones , coumarins , and other ingredients . CTAB extraction genomic 18S rDNA PCR amplification , amplification products were purified , sequenced by molecular identification of significant antibacterial activity of metabolites of endophytic fungal strains (S4) , and results show that the S4 strain ascus Block genus of bacteria Amon fungus (Diaporthe) . Pyracantha endophytic fungi S4 antibacterial the structure of the active ingredient to be further studied .
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