Abstract:

AM fungi infection rate, spore density, diversity and distribution in the main plant species at different vegetation restoration stages in Loess Hilly Gully Region were studied. The results showed that 18 AM fungus species, belonging to Gigaspora, Scutellospora and Glomus, were identified from the rhizospheres of the main plant species. Glomus constrictum and Glomus geosporum of Glomus were the common species at different vegetation restoration stages, and they are also the dominant species in the region. Distribution of the other 16 species varied at different stages. There were significant differences in the average infection frequencies of host plants between the first and second stages on sunny slopes. However, the spore density had no significant difference among the five stages. By contrast, there was no significant difference in the infection frequencies among the five stages on shady slopes, and the spore density at the fourth and fifth stages was higher than that at the first and second stages. Richness and diversity of the fungus species were higher at the fourth and fifth stages, and lower at the first and third stages regardless of slope aspect. On sunny slopes, evenness of AM fungi at the second, third and the fourth stages were higher than that at the fifth stage. However there was no significant difference in the evenness on shady slopes. These results are important for further studying the relationships between AM fungi diversity and plant community species diversity in the region, and even greater important for sieving AM applying fungi species with adaptive ability and applying mycorrhizal biotechnology to vegetation restoration in Loess Plateau.

Key words: arbucsular mycorrhizal fungi, spore density, infected frequencies, diversity, Loess Hilly Gully Region