岷江干旱河谷小马鞍羊蹄甲根围丛枝菌根真菌群落的研究

丛枝菌根真菌（arbuscular mycorrhizal fungi,AMF）在促进植物生长及土壤改良等方面的积极作用使其在退化生态系统的植被重建过程中发挥着关键作用。本研究采用建立克隆文库及测序的分子方法对四川省岷江干旱河谷乡土优势灌木小马鞍羊蹄甲Bauhinia faberi var. microphylla根围AMF的群落组成进行了探讨,以期为该地区乡土植被的保存与恢复提供理论依据。本研究中共检测到53个AMF类群（OTUs）,通过系统发育分析,将其划分为球囊菌门Glomeromycota的7科10属。Glomus、Diversispora与Funneliformis 3个属为小马鞍羊蹄甲根围土壤中的优势属,其中Glomus具有最高多度,其序列数及OTUs数均占总数的50%以上;Rhizophagus与Archaeospora为稀有属,其余各属为常见属。本研究表明,自然条件下研究区优势灌木小马鞍羊蹄甲根围具有相对丰富的AMF类群,同时也反映了AMF在干旱河谷区可能发挥着重要的生态功能。

The community composition of arbuscular mycorrhizal fungi in the rhizosphere of Bauhinia faberi var.microphylla in the dry valley of Minjiang River

Arbuscular mycorrhizal fungi (AMF) can effectively improve plant fitness and soil quality, thus they play an essential role in soil remediation and revegetation in these degraded ecosystems. Using cloning and sequencing methods, we examined the AM fungal assemblages in the rhizosphere of Bauhinia faberi var. microphylla which is a dominant shrub species in the dry valley of Minjiang River of Sichuan Province for facilitating theoretical studies on preservation and recovery of native vegetation. We detected 53 AMF operational taxonomic units (OTUs) which were assigned to 7 families and 10 genera of Glomeromycota based on phylogenetic analysis of sequences. Glomus, Diversispora and Funneliformis were dominant genera in the rhizosphere of the plant. Glomus taxa were most abundant, accounting for more than 50% of the total OTUs and sequences, respectively. Rhizophagus and Archaeospora were relatively rare, and the rest were common genera. Our results reveal that there is a high level of AMF diversity in the rhizosphere of the target plant species, and these abundant AMF taxa may play an important ecological role in this arid region.