Plant Diversity and Root Traits Shape Rhizosphere Microbial Communities in Natural Grasslands and Cultivated Pastures

The rhizosphere microorganisms are essential for plant nutrition and protection. The rhizosphere composition is passively or actively selected by root plants. Plant diversity can shape rizhospheric recruitment, but little is known about the influence of root traits. Here, we used bacterial 16S rRNA and fungal ITS region, to test the hypothesis that plant diversity and root traits influence the diversity and microbial composition of the rhizosphere of natural grasslands and cultivated pastures. We evaluated whether Bacteria and Fungi have different responses to changes in plant diversity and root traits. The rhizosphere and bulk soil were collected in two subtropical highland grasslands: improved-natural grassland (IG) and annual-cultivated pasture (AP). Our results have indicated that the bacteria and fungi community structure differed between grassland systems and rhizosphere and bulk soil. No differences were found in bacterial richness and alpha diversity between grassland systems, while the fungal alpha diversity was higher in the AP rhizosphere. The diversity, composition, and root characteristics of grassland plants have influenced the selection of specific groups of soil bacteria and fungi.