Study On Endophytic Fungi Resources And Biological Control Dry-rot Bacteria Of Chestnut

An plant endophytic fungis colonizes symptomlessly the living,internal tissues of the host plant. The plant endophytic fungi plays an important role in ecosystem. Its diversity of secondary metabolites deserved comprehensive attention and made great progress in the world. So the plant endophytic fungis are regarded as rich resources of natural active materials and to be great using potential in some aspects,such as preventing and curing some kinds of plant diseases,producing medicines and curing human diseases.Chinese Chestnut plants are important economic trees.They distribute widely and are planted popularly,so they occupy an important station in our national economy.Chest nut dry rot is one of the common diseases seriously affected the quality of Chinese chestnut during storage period, therefore, it is of great significance to cure the chestnut stem rot disease. for it is a lot of control research, and the use of endophytic fungi of chestnut for the biological control of dry rot has not yet been reported. In order to know the population composition of endophytic fungi living in Chinese Chestnut plants,microecological function and some important metabolite,which are produced in their growth,as well as to provide a theory direction,Chinese Chestnut garden samples were selected to survey the species of endophytic fungi which live in different Chestnut organs.The fungi of biological function were tested and metabolite of some fungi were preliminary studied.The study showed that there were abundant resoures of endophytic fungi living in Chinese Chestnut plants in the country.they were constituted with ascomycetes and deuteromycetes.In the paper,339 stains of endophytic fungi were isolated Chinese Chestnut.They were identified Phomopsis sp.,Alternia sp.,Peni. cillium spp., Aspergillus spp. and so on based on morphological taxonomy.There were different endophytic fungis in the different Chestnut plantations.It was related with their entironment.The endophytic fungi in a kind of Chestnut organ were different from those of other kinds.Abundance of endophytic fungi was the highest in Chestnut leaves,there were no ones or few ones in Chinese Chestnut seeds and xylem,there were endophytic bacteria in Chinese Chestnut seeds and xylem.The species of endophytic fungi in different tissues were different for the same organ too.The study showed that fermentation liquid 4 stains can inhabit dry-rot bacteria well. Mycelial growth by observing the shape and weigh the dry weight of mycelium research chestnut stem rot bacteria and fungi within the B2, P1 and C1 of the interaction effects. The results show that the endophyte mycelium of B2,P1 and Cl extracts have significant inhibitory effect on pathogenic bacteria.The test was done at 25℃and 120r/min on the mycelial biomass. After the single factor experiments the most suitable carbon source, nitrogen source and the most suitable pH were decided.Experiments show that the most suitable carbon source for B2 is glucose, the most suitable nitrogen source for B2 is yeast cream,and the most suitable PH for B2 is PH 5.0. Besides experiments show that the most suitable carbon source for D1 is sucrose, the most suitable nitrogen source for D1 is peptone,and the most suitable PH for D1is pH 6.2.The most suitable solid medium compounding is the first compounding for B2, the most suitable solid medium compounding is the second compounding for D1.