Diversity and Spatial Heterogeneity of Arbuscular Mycorrhizal Fungi in the Rhizosphere of Ammopiptanthus nanus

The study was used to discuss the change law of diversity and spatial heterogeneity of AM fungi in the Ammopiptanthus nanus.Four genera and 44species of AM fungi were isolated and determined from the soil samples of four different sites,which there were Glomus 28species,Acaulospora11species,Scutellospora4species,Gigaspora1species,G.reticulatum was the predominant species.The spore was characterized by its low density,small shape,thick wall and un-full overall shape,that indicated AM fungal spore had the obvious ecological adaptability.The highest spore density of AM fungi was at Biaoertuokuoyi(yin)site,and was significantly higher than other sites.The species richness of Kangsu,Biaoertuokuoyi and Shangatushi sites increased successively and had significant difference.The Simpson's diversity index at Kangsu,Biaoertuokuoyi(yang)and Shangatushi sites hadn't significant difference.The Shannon-wiener diversity index at Bieoertuokuoyi(yin)and Shangatushi sites were significantly higher than others.The evenness at Biaoertuokuoyi(yang),Biaoertuokuoyi(yin),Kangsu and Shangatushi sites increased significantly in turns.Available P had significantly negative correlations with species richness.Soil pH had significantly positive correlations with species richness.Soluble salt had significant negative correlations with Shannon diversity and Evenness indices.Total N had significant negative correlations with species richness.Our results suggest that the species diversity of AM fungi in the rhizosphere of A.nanus had obvious spatial heterogeneity and had close correlations with its soil environment,so that pH was the most important,and pH was the most important soil factor that affect the species diversity of AM fungi in the rhizosphere of A.Nanus.