铜镉复合胁迫下硫素对小麦幼苗铜镉吸收、亚细胞分布及毒性的影响

采用水培的方法,研究了不同硫素供应水平对铜镉复合胁迫(Cu+Cd:10μmol·L-1+10μmol·L-1)下,小麦幼苗铜镉吸收、亚细胞分布及生理毒性的影响.结果表明,缺硫和高硫处理均降低了小麦幼苗根系和叶片中铜和镉的含量,不同硫水平处理对小麦幼苗根系亚细胞各组分中镉的分配比例没有产生影响,而对铜亚细胞组分的分配比例...

Influence of Sulfur on Subcellular Distribution,Uptake and Toxicity of Cu and Cd to Wheat Seadlings

A solution culture experiment was carried out to investigate the effects of sulfur on the uptake, subcellular distributions and toxicity of copper (Cu) and cadmium (Cd) to wheat seedlings. The result indicates that both the high sulfur and no sulfur treatment could decrease Cu and Cd content in the roots and leaves of wheat seedlings. Different sulfur supply levels did not affect the subcellular distributions of Cd in the roots of wheat seedlings, while it induced significant changes on the subcellular distribution of Cu. The treatment supplied with sulfur increased the allocation proportion of Cu in soluble fraction and decreased it in cell wall fraction, while opposite results were concluded in no sulfur treatment experiments. Combined treatment of Cu and Cd generated obvious toxicity to wheat seedlings. Specifically, they made decrease in plant biomass, chlorophyll content, reduced glutathione (GSH) content and the activities of superoxide dismutase (SOD) and catalyses (CAT), and increase in the content of MDA in wheat seedlings roots. Compared with moderate sulfur treatment, high sulfur treatment significantly increased the plant growth, the content of chlorophyll and reduced glutathione (GSH), and the activity of superoxide dismutase (SOD) and catalyses (CAT), whereas clearly decreased the content of MDA in wheat seedlings. The non-sulfur treatment results were adverse.