ABSTRACT

A potential plant species suitable for As bioaccumulation and phytoremediation of water environments could be the macrophyte Berula erecta. The objective of the present study was to investigate the effect of arsenate (As(V), C2H6AsNaO2∙3 H2O), predominant in freshwater systems, on the growth, development and low molecular weight thiols of Berula erecta under controlled tissue culture conditions in vitro. Uptake of total arsenate increased with increasing arsenate treatments, at a higher percentage in the roots than in the aboveground parts of the plants. Lower concentrations of As(V) (0.1, 1, 10 mg L−1) had a positive effect on growth, dry weight, length of roots and shoots and number of buds. High concentrations of arsenate (50 and 100 mg As(V) L−1) significantly inhibited all growth parameters and decreased the photochemical efficiency of PSII. Evaluation of thiols revealed the critical As level (146 µg g−1 DW; 50 mg As(V) L−1 treatment) above which the As concentration can be toxic.

摘要

适合 As 生物富集和水环境植物修复的潜在植物物种可能是大型植物 Berula erecta。本研究的目的是研究淡水系统中主要的砷酸盐 (As(V)、C2H6AsNaO2∙3 H2O) 在体外受控组织培养条件下对Berula erecta生长、发育和低分子量硫醇的影响. 总砷酸盐的吸收随着砷酸盐处理的增加而增加，根部吸收的百分比高于植物的地上部分。较低浓度的 As(V)（0.1、1、10 mg L−1）对生长、干重、根和芽的长度以及芽数有积极影响。高浓度砷酸盐（50 和 100 mg As(V) L-1）显着抑制所有生长参数并降低 PSII 的光化学效率。硫醇的评估揭示了临界 As 水平（146 µg g−1 DW；50 mg As(V) L−1 处理），高于该水平 As 浓度可能有毒。