Species Diversity Of Dematiaceous Hyphomycetes From Soil In Northern Qinghai Provice

The species of Fungi Imperfeci are most abundant in the soil, of which dematiaceous hyphomycetes account for about or more than one half of it. China spans warm temperate zone, temperate zone, subtropical zone and tropical zone. Therefore, soil and vegetation types are very plentiful. Soil as a complex ecosystem, may contain plenty of fungi resource. Qinghai province located in the Northwest of China is plateau continental climate. The altitude of its most area is about 3,000 to 5,000m, and the natural ecosystem is complex. The natural ecosystem in northern Qinghai can be divided into many types, such as, mountain, desert, gobi, farmland, grassland, saline, forest, swamp, and so on. The species diversity of soil dematiaceous hyphomycetes is deeply influenced by the condition of natural ecosystem, especially by the soil environment which they live in.This study is a part of a project on fungal diversity of dematiaceous hyphomycetes from soil in China. It aimed at clarifying the diversity at genus and species level, the distribution status and the ecological significance of the soil dematiaceous hyphomycetes in the northern area of Qinghai province, and exhuming fungi resources to accumulate information for the latter research.For this purpose 171 soil samples were collected from representative sites in the northern area of Qinghai province in 2006-2007. From which, 305 fungal isolates were got by soil plate methods and dilution plate methods. A total of 82 species belonged to 27 genera of dematiaceous hyphomycetes were identified. Among them, 68 species in 22 genera are Hyphomycetales, 8 species in 3 genera are Stilbellales and 6 species in 2 genera belong to Tuberculariales. The fungi mentioned above include 12 new species, 2 undeterminated spp., 3 new records for China and 1 new record for the mainland of China. All genera and species are fully described and illustrated morphologically. Distribution sites, habitat and altitude are also cited. Latin descriptions are given for the new species.New species: Drechslera citrea, Gliomastix brachypodi, Gliomastix tuberculatum, Humicola irregularis, Monodictys qaidamensis, Scolecobasidium ellipsoideum, Scolecobasidium levis, Scopulariopsis interseminata, Scopulariopsis microspora, Scopulariopsis verrucaria, Stachybotrys variabilis, Myrothecium macrospora.The two undeterminated species: Hansfordia sp.1, Helicoma sp.1.New records for China are: Cirrenalia macrocephala (Kohlm.) Meyers & R.T. Moore, Veronaea simplex M.C. Papendorf, Myrothecium indicum Rama Rao.The new records for the mainland of China is Chloridium phaeosporum W. Gams & Hol.–Jech. var. cubense Hol.–Jech..All specimens (dried cultures) and living cultures studied are deposited in the Herbarum Shandong Agriculture University, Plant Pathology (HSAUP), at the same time all isolates are deposited properly. Based on those works, we studied and thought the culture methods and taxonomic criteria of genera and species of soil fungi, then advanced our viewpoints.Duing to various ecosystem types and special geographical position, We used species dominance, Shannon-Wiener index, evenness and niche width to study the diversity of genus species of soil dematiaceous hyphomycetes in different ecosystem types of Qaidam Basin, aiming at studying the influence of human activity to distribution of the soil microbes in relative isolation environment. The results showed that the dominance of different genus species in the four ecosystem types had a distinct difference. The index of genus species diversity and the evenness were closely related to the soil humidity, vegetation and human factor. And the indexes of gobi and desert were distinctly lower than in town-oasis. In the four ecosystem-types, the niche breadth of genus species had a great difference. Some genus species had wider niche breadth and were widely adaptive species. However, some had narrower niche breadth and were narrowly adaptive species.