Diversity And Community Composition Of AM Fungi In Rhizosphere Of Hedysarum Leave In Saibei Sandland,North China

In the present study,we expect to elucidate the diversity and ecological distribution of AM fungi associated with clonal plants Hedysarum leave Maxim at Qinggeletu in Inner Mongolia,China.Soil samples were collected in the rhizospheres of H.leave Maxim at three different altitude gradients habitats: the foot-slop,middle-slop and top-slop of the terrace.The community composition and diversity of AM fungi were analyzed based on nested-PCR-DGGE fingerprint and high-throughput sequencing(18S rDNA).The main results are as follows:1.The results of DGGE fingerprint revealed significant differences in the composition,richness,dominance and diversity of the AM fungi communities between different soil layers and habitats.The richness of AM fungi community recorded in the 0-10 cm layer at the middle-slop and top-slop of the terrace,which was the highest among the sampling habitats.The highest diversity index was recorded in the 0-10 cm layer at the middle-slop of the terrace.Sequencing and phylogenetic analysis showed that all the sequences were closely related to 15 species belonging to 5 genus,i.e.,Glomus(10 species),Funneliformis(2 species),Paraglomus(1 species),Rhizophagus(1 species),and Septoglomus(1 species).Clustering analysis showed that greatly differed from each other as the highest similarity index was merely 0.54.This meant that the diversity of AM gungi community in the rhizospheres of H.leave Maxim was significantly influenced by the heterogeneity of the three habitats.Due to the dominance of Glomus and Funneliformis in the AM fungi communities in the deserts of Inner Mongolia,high-efficiency species or stains belonging to the two genus may be selected for improving plant establishment and vegetation rehabilitation in this area.2.The results of Illumina HiSeq 2500 platform revealed,through the 97% similarity of sequence clustering,we obtained total 486 OTUs,252 belonged to Glomeromycota across all 3 classes,4 orders,10 families,and 18 genera.The abundance of Glomeromycota was higher in foot-slope than in top-slope,and Glomeraceae presented the highest relative abundance in all the samples.Sclerocytis and Glomus were the most abundant genera in all the samples,Clarodeoglomus,Rhizophagus,and Gigaspora exhibited higher relative abundances.Paraglomeraceae was not found in the foot-slope,Geosiphonaceae was not noted in the mid-slope,and Ambisporaceae and Pacisporaceae were not detected in the top-slope.3.Canonical redundancy analysis suggested that soil pH,soil organic carbon(SOC),total N(TN),total P(TP),available N(AVN),and available P(AVP)were significant factors that shaped the AM fungal composition and diversity.The different slope sites might influence AM fungal diversity and composition,providing the basis for elucidating their ecological function in desert ecosystem.