Diversity of arbuscular mycorrhizal fungi in the rhizosphere of three host plants in the farming-pastoral zone, north China

The spatial diversity and distribution of AM fungi were investigated in three plots located in farming-pastoral zone, north China. The rhizospheres of Caragana korshinskii, Artemisia sphaerocephala and Salix psammophila were sampled and thirty AM fungal species belonging to five genera were isolated. The study demonstrated that AM fungal diversity and distribution differed significantly among the three host plants and the three studied plots. Spore density of AM fungi ranged between 2 and 22 spores per g(-1) of soil and species richness between 8 and 23. Correlation coefficient analysis demonstrated that spore density was significantly and positively correlated with soil organic matter and available N (P < 0.01). Species richness was significantly and positively correlated with soil organic matter and available P (P < 0.01), but significantly and negatively correlated with soil pH (P < 0.01). Finally, the Shannon-Weiner index was significantly and positively correlated with soil organic matter (P < 0.05). In this farming-pastoral zone, Glomus reticulatum and G.melanosporum may be more adaptable to the arid conditions than other AM fungal species. This research into AM fungal diversity may lead to exploitation of AM fungi for the mitigation of soil erosion and desertification using mycorrhizal plants, such as C.korshinskii, A.sphaerocephala and S. psammophila. The results of this study support the conclusion that diversity and distribution of AM fungi might be useful to monitor desertification and soil degradation.