Phytoremediation of diphenylarsinic-acid-contaminated soil by <i>Pteris vittata</i> associated with <i>Phyllobacterium myrsinacearum</i> RC6b

<p>A pot experiment was conducted to explore the phytoremediation of a diphenylarsinic acid (DPAA)-spiked soil using <i>Pteris vittata</i> associated with exogenous <i>Phyllobacterium myrsinacearum</i> RC6b. Removal of DPAA from the soil, soil enzyme activities, and the functional diversity of the soil microbial community were evaluated. DPAA concentrations in soil treated with the fern or the bacterium were 35–47% lower than that in the control and were lowest in soil treated with <i>P. vittata</i> and <i>P. myrsinacearum</i> together. The presence of the bacterium added in the soil significantly increased the plant growth and DPAA accumulation. In addition, the activities of dehydrogenase and fluorescein diacetate hydrolysis and the average well-color development values increased by 41–91%, 37–78%, and 35–73%, respectively, in the treatments with <i>P. vittata</i> and/or <i>P. myrsinacearum</i> compared with the control, with the highest increase in the presence of <i>P. vittata</i> and <i>P. myrsinacearum</i> together. Both fern and bacterium alone greatly enhanced the removal of DPAA and the recovery of soil ecological function and these effects were further enhanced by <i>P. vittata</i> and <i>P. myrsinacearum</i> together. Our findings provide a new strategy for remediation of DPAA-contaminated soil by using a hyperaccumulator/microbial inoculant alternative to traditional physicochemical method or biological degradation.</p>