硅对镉胁迫下水稻幼苗体内镉分布规律的研究

Study on the Cadmium Distribution Regulation of Cadmium Stress by Silicon in Oryza sativa Seedlings

采用溶液培养,研究不同浓度(0、30、80、130、180mg/L)的SiO2在4.0mg/LCdCl2浓度胁迫下对水稻幼苗体内镉(Cd)的分布规律。结果表明,在Cd胁迫下Si降低了水稻幼苗根、茎、叶、鞘、共质体和质外体Cd含量,其分布规律为:根>茎叶>茎鞘>叶片,呈现出末端分布规律。说明Si促使大量的Cd累积在根中,根是Cd累积的主要部位,而茎、叶中Cd累积量较少。可见,Si可抑制水稻体内Cd由地下部分向地上部分运输,且能抑制地上部分Cd向叶片运输,并能减少Cd进入共质体。

The cadmium distribution regulation of cadmium stress by silicon in the Oryza sativa seedlings was studied by hydroponic culture method. Oryza sativa seedlings were treated with CdC12 at 4.0mg/L and SiO2 at 0,30,80,130,180mg/L concentrations. The results showed that silicon reduced cadmium content in the root, stem, leaf, symplast and apoplast of the Oryza sativa seedlings under cadmium stress. The distribution of Cd was root〉stems and leaves〉stem sheath〉leaves, showing the terminal distribution. A great deal of Cd was accumulated in root. So the root was the main site of Cd accumulation, and the stems and leaves accumulated less Cd. This indicated that silicon could inhibit the transportation of cadmium from underground part to above ground part, and from above ground part to leaves of rice plant. Silicon could also reduce Cd transported into the symplast.