Fungal community diversity and driving factors in rhizosphere soil of Caragana species across semi-arid regions

Abstract

To investigate fungal community diversity in rhizosphere soil of Caragana species, and their relationships with ecological factors in the semi-arid regions of China, we collected soil samples from Caragana liouana and C. microphylla in different habitats. By using Illumina MiSeq high-throughput sequencing technology, we analyzed fungal diversity, community composition, and the driving factors. Results showed that 7 phyla, 20 classes, 43 orders, 66 families, and 78 genera were recorded from the rhizosphere soil. The dominant phyla in all sample sites were Ascomycota (37.7%), Basidiomycota (13.7%), and Zygomycota (4.3%). At the genus level, Penicillium, Geomyces, and Mortierella were dominant, and Rhizophagus and Glomus were also found in rhizosphere soil. The fungal Chao1 index, ACE index, and Simpson index of C. microphylla were significantly higher than those of C. liouana. There was significant difference between the two species in the composition of fungal communities. Results of redundancy analysis showed that soil organic carbon, total nitrogen, electrical conductivity, available potassium, altitude, total phosphorus and aridity index exhibited significant impacts on soil fungal diversity. Overall, those results enhanced our understanding of the relationships between rhizospheric microbial community diversity of Caragana species and ecological factors, and provided important information on the adaptive mechanisms of desert plants in semi-arid regions.