| Tibet is the main part of the Tibeten Plateau, covering 1/8 of national territory area ,and its average elevation is over 4000m. The climate, topography and vegetation in this area are complicated. The soil can contains special group of the soil fungi. The study of the moniliaceous hyphomycetes of this area proved to be favorable to the diversity of soil-inhabiting fungi. The following are results:1.This study clarified the diversity at genus and species level, the survival and distribution status and the ecological significance of the soil moniliaceous hyphomycetes form the Himalayas to the Yarlung Zangbo River, Tibet. In this study, the 96 soil samples were collected from this area, and the 674 fungal isolates were got from those soil samples by soil plate methods and dilution plate methods. Determination of the isolates belonged to 14 genera including Acremonium, Beauveria, Chrysosporium, Gliocladium, Aspergillus, Trichoderma, Stachybotrys, Penicillium, Paecilomyces, Mariannaea, Fusarium, Metarhizium, Volutella, Verticillium and Fusarium. Detailed descriptions and illustrations of the above genera and 17 species and three undeterminated species inside isolated are given and the locus, altitude and entironment of all soil samples are registered except Fusarium. All specimens (dried cultures) and living cultures studid have been deposited in the Herbarium of Shandong Agricultural University: Plant Pathology (HSAUP).2. Based on the morphological taxonomy, 5.8S rDNA–ITS partial sequences from from two species in Acremonium, one species in Beauveria, one species in Chrysosporium, fourteen species in Gliocladium, one species in Trichoderma, one species in Stachybotry, two species in Penicillium, three species in Mariannaea, three species in Paecilomyces, one species Metarhizium, and three species in Volutella were determined and compared. Phylogenetic trees of the 5.8S rDNA–ITS about Gliocladium, Paecilomyces and its two kinds of similar genera including Penicillium and Mariannaea, and the other six genus were seted by NJ method. The results showed that 5.8S rDNA–ITS could separate most of genera and species clearly of the soil moniliaceous hyphomycetes which were consistent with results of morphological taxonomy. But different isolates of Gliocladium had different cultural characters and morphological characteristics while 5.8S rDNA–ITS sequences were hightly conserved, not enough variability present to distinguish species clearly.3.The population dominance index, Shannon-Wiener index, evenness, niche breadth and community similarity were used to analyze the diversity and echo-niche of soil moniliaceous hyphomycetes in five ecosystem-types of the middle reach of Yarlung Zangbo River of Tibet.. The results showed that the amount and species (genus species) distribution of soil moniliaceous hyphomycetes had an obvious variability in different ecosystem-types. The diversity index of farmland was the highest and the evenness was higher while the diversity index of shelter belt was the lowest and the evenness was lowest too. For the analysis of similarity between different ecosystem-types showed that the farmland and shelter belt ecosystem-type had the highest similarity, which indicated that the soil moniliaceous hyphomycetes in this two ecosystem-types had more common species. And the similarity coefficient between wetland and garden ecosystem-type was the lowest. The results of niche breadth analysis indicated that Paecilomyces, Volutella, Aspergillus and Penicillium had wider niche breadth and were widely adaptive species. While Beauveria and Metarhizium had narrower niche breadth and were narrowly adaptive species in the five ecosystem-types.
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