Abstract
Arsenic hyper-accumulators such as Pteris vittata have been known applicable to purify arsenic pollution from the soil. The present study focuses on the phytoextraction of arsenic and aims to clarify the participation of microbes in the arsenic absorption by Pteris vittata. The cultivation experiments of Pteris vittata have been performed to investigate the transition of arsenic from the soil to Pteris vittata. The results show that the arsenite in the soil is promptly oxidized to arsenate and subsequently absorbed by Pteris vittata. The arsenic oxidation experiment in the soil with soil bacteria addition has been peformed, and the speciation of arsenic in the soil has been investigated. The results suggest that soil bacteria are responsible for the arsinite oxidation. T-RFLP analysis targeting to arsenite oxidase genes, aroAs, has been applied to analyze the microbial community in the rhizoshpere of Pteris vittata. The results suggest that specific aroA containing bacterial strains are involved in the arsenite oxidation prior to being absorbed by Pteris vittata.
