Community Diversities Of Endophytic Fungi In Poplar And Preliminary Screening Of Biocontrol Endophyte To Ctyospora Chrysosperma

In China, Poplar was considered as the major species for afforestation whereendophytic fungi were abundant. It was found that some endophytic fungi not onlyabsorbed nutrients from Poplar for their growth, but also promoted the growth of Poplarand had the ability of resisting to certain diseases to enhance the resilience of the tree. Inthis study, endophytic fungi were isolated from leaves, twigs, tree barks and roots of freshand healthy Poplar collected randomly by the method of tissue isolation to discuss thecommunity diversity of endophytic fungi in Poplar. The methods of dual culture,antagonism of active materials, germination of spores, artificial inoculation experimentwere used for screening endophytic fungi which resists to Ctyospora chrysosperma.1.941strains of endophytic fungi were isolated from fresh and healthy Poplar.Through classification identification, it was found that888strains of these fungi belongedto two subphylum, four classes, six orders, seven families, sixteen genera. Others with nosporulation were classified as unknown fungi.The sixteen genera were Capnodium sp.，Phomopsis sp.，Phyllosticta sp.，Phoma sp.，Cytospora sp.，Fusicocum sp.，Sphaeropsissp.，Croyneum sp.，Alternaria sp.，Cladosporium sp.，Penicillium sp.，Trichoderma sp.，Aspergillus sp.，Cephalosporium sp.，Nigrospora sp.，Chaetomium sp..Alternaria sp. andPhoma sp.were the dominant strains in Poplar and their separation frequency was62.81%and19.77%, respectively.2.The results showed that endophytic fungi in Poplar were diverse. The componentand number of endophytic fungi in Poplar were related with parts, ages, species and placesof Poplar. The component and number of endophytic fungi in leaves and phloem of twigswere most abundant. The composition of endophytic fungi in Poplar were changeddynamically with the increasing of ages. Compared with other species, the diversity indexof P．Canadensis Moench was the highest. The number and component of endophyticfungi were affected by different parts, species of Poplar and the environmental factors, sothe endophytic fungi were specificity to the parasitifer and tissue which they parasitized. 3.With the methods of the dual culture, antagonism of active materials, germination ofspores and inoculation experiment,11Y1、16GR3、17GR7、CD.ZR5were selected becausetheir strongest antifungal effectiveness to Ctyospora chrysosperma.11Y1、16GR3、CD.ZR5were Chaetomium sp..17GR7was unknown for none spores.