Abstract: In order to elucidate the morphological structure and ecological adaptability of arbuscular mycorrhizal fungi in arid environment, some soil samples were collected from the rhizosphere of Hippophae rhamnoides L. at four sapling sites in a farmingpastoral ecotone in a region between Inner Mongolia and Hebei Province in July 2009. Seventeen AM fungal species in three genera were isolated and identified with optical microscope and scan electricity microscope. In which 11 species were in Glomus, 5 in Acaulospora and 1 was in ]Scutellospora. The results indicated that AM fungal spore had the obvious ecological adaptability, and the spore was characterized by its small shape, deep color, thick wall and un-full overall shape. SEM showed that fungal spore morphology was different among the 17 species, especially in surface veins, which can be used as a reference index for AM fungal identification.

Key words: Hippophae rhamnoides L., AM fungi, morphological structure, ecological adaptability, farming-pastoral ecotone