Molecular Diversity of Arbuscular Mycorrhizal Fungi in a Chronosequence of Caragana korshinskii Plantation
不同演替阶段人工柠条林丛枝菌根真菌分子多样性研究

We used PCR-DGGE, DNA cloning and sequencing techniques to study the community structure and diversity of arbuscular mycorrhizal fungi (AMF) in a chronosequence of Caragana korshinskii plantation in gully region of the Loess Plateau. Phylogenetic analysis of all DNA sequences revealed four sequence groups, of which all grouped in the genus of Glomus. The four sequence groups showed high similarity to Genbank sequences of G. intraradices, G. fasciculatum, Glo18 and G. sp. respectively. Our results indicated an extremely low diversity of AMF presented in the C. korshinskii roots in a sampling time point. All of the four sequence groups presented in 5, 13 and 20-year sites, but G. sp. were not distinctly detected in 42-year site. It suggested AMF community composition in a chronosequence of C. korshinskii plantations was stable, and implicated the restoration of AMF community was not successful with the succession of C. korshinskii plantations. The little edaphic variation and the positive feedback relationship between AMF and plant communities in C. korshinskii plantation maybe result in such a phenomenon.