The role of arsenate reductase (AR) in As accumulation in four Pteris species

摘要

Arsenlc (As) contamination of soil/water has imposed health hazards. Using As hyperaccumulators to extract As from contaminated solls is a good way. Most of the known As hyperaccumulators are belonged to Pteris species. Present study aims to explore the responses and role of arsenate reductase (AR) in As hyperaccumulators fern species (Pteris vittata, P. multifida) and no As hyperaccumulators species (Pteris ensiformis, P. semipinnata) when grown in soils added 0 (control), 100, and 200mg/kg of arsenic. The results show that (1) except for P. semipinnata, the AR activity and total As concentration in roots of all fern Plants is increased with the Increase of As in soils, (2) the AR activity is significant higher in roots than in fronds. These results suggest that most of arsenate taken up by the Pteris plants is reduced to arsenite in root tissues, and enhanced AR activity is related to the increased As accumulation in these plants. Based on previous and present results, we conclude that arsenate reduction isa very importam step tor As transporting and accumulation in fronds, and the AR in roots plays as a very important role in this step in Pteris species.