| Endophytic fungi involving in many kinds of gramineous plants complete their parts or whole lifecycles within plants, but do not cause any symptom, which is a kind of new-type bioresources that play more and more attention. Endophytic fungi distribute in above 80 genuses, 290 species gramineous plants and show rich diversity. It has relatively strict host specificity, which makes artificial inoculation with endophytes more difficult.Firstly, 291 gramineous plant samples belong to 3 genra were selected from 4 cities of 3 provinces in China. 17 Roegneria spp. samples were collected from Tanshan, Hebei, with endophyte level of 23.5%; 38 Roegneria spp. samples were collected from Huaian, Jiangsu, with endophyte level of 21.1%; 139 Roegneria spp. samples were collected from Nanjing, Jiangsu, with endophyte level of 35.3%; 27 Roegneria spp. samples were collected from Fuzhou, Fujian, with endophyte level of 55.6%; 50 Agrostis alba samples were collected from Nanjing, Jiangsu, with endophyte level of 78%; 20 Festuca arundinacea samples were collected from Nanjing, Jiangsu, with endophyte level of 33.3%. There are abundant endophytic fungus resources in China.Secondly, from plant samples containing endophytic fungus indicated above, 26 isolates were isolated and cultured on PDA plates. These 26 isolates were morphologically identified as 4 species in 2 genera due to their cultural properties, morphological characteristics and the species of each host . 13 isolates from Roegneria kamoji were identified as "Epichloe sp.", 6 from Roegneria spp. were "Neotyphodium typhinum ", 1 from Roegneria sp. and 3 from A. alba were "N. starrii", and the remaining 3 isolates from F. arundinacea were "N. coenophialum". It indicated that endophytic fungi inhabiting in gramineous plants grown in China diverse in their species. With microscopic examination, endophytic mycelia show some tissue specificity, ie, it presents in leaves, stems and aleuron cells of seeds, and host specificity, ie, it presents only in specific hosts. All isolates cultured on PDA and MM plates show physiological diversity. N. typhinum and N. starrii show some regiondiversity. Different isolates of same species show significent morphological diversity: Epichloii sp. on colony morphology and growth speed, N. typhinum and N. starrii on colony morphology, growth speed and the shape and size of conidiospores and conidiophialides, N. coenophialum show less diversity. N. starrii were firstly obtained in Roegneria sp. in China and Epichloe sp.maybe a new species which different with others. This study indicates that the endophytic fungus resouces of China show extensive biodiversity.Thirdly, 4 kinds of endophyte-free seeds including Rustmaster (Lolium prenne), Jiamei (Festuca arundinacea), Gaodi (Agrostis sp.) and Cristatum (Agropyron cristatum cv. Kirk) were used for plant materials of artificial inoculation and 14 endophyte isolates obtained in this study were selected as endophyte inoculum. Artificial inoculation was proceed by following 4 methods: seedling injection, seedling slit, seed slit and callus culture. Seedling injection and seed slit were failed for successful endophyte inoculation. The successful endophyte inoculation was achieved for the first time in China through callus culture inoculation and seedling slit inoculation, with inoculation efficiency of 5.1% and 1% respectively, lower than international level. Several novel endophyte-grass associations were obtained as follow: N. typhinum-L perenne, Epichloe sp.- L. perenne and Epichloe sp.-F. arundinacea.At last, we examined endophyte compatibility with plants through inoculation. Demonstrated that the mycelium of N. typhinum in L. perenne, F. arundinacea, Agrostis sp. and Agropyron crislatum cv. Kirk that was appeared curl, fewness embranchment, showed well compatibility and less host specificity. N. starrii in L perenne and Agrostis sp. which mycelium appeared curl, fewness embranchment, showed well compatibility and some host specificity. Epichloe sp. in L perenne and F. arundinacea which mycelium appeared hig...
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