The effects of ectomycorrhizal fungi on heavy metals’ transport in Pinus massoniana and bacteria community in rhizosphere soil in mine tailing area

Abstract

Pinus massoniana is one of the potential tree species of afforestation in barren mine tailing area, and ectomycorrhizal fungi contributes remarkably to its survival. However, how ectomycorrhizal fungi interacts with Pinus massoniana under heavy metals’ stress is unknown. Two systems (Pinus massoniana inoculated with and without ectomycorrhizal fungi) were designed, and each system contained rhizosphere and non-rhizosphere, while bulk soil was sampled as control. The results showed that treatment of ectomycorrhizal fungi inoculation could obviously improved the absorption of soil moisture, total carbon/total nitrogen and nutrients, while reduced the bulk density and heavy metals of soil when compared with control (p＜0.05). The heavy metals accumulating in plants’ roots with ectomycorrhizal fungi were greater than that without ectomycorrhizal fungi. Conversely, they were lower in shoots with ectomycorrhizal fungi. The bacterial community were affiliated with 23 bacterial phyla, 70 classes, 115 orders, 201 families, and 363 genera. Constrained Principal Coordinate Analysis and redundancy analysis demonstrated that bacterial communities structure in the soil inoculated with or without ectomycorrhizal fungi and bulk soil were distinguishable, but no difference between rhizosphere and non-rhizosphere. The LEfSe analysis showed Acidobacteria, Actinobacteria, and Proteobacteria were the dominant phyla that contributed to the difference among treatments.