硅缓解小麦镉毒害的效应研究

ALLEVIATION OF CADMIUM TOXICITY OF WHEAT PLANTS BY SILICON

采用水培试验研究了不同S i,Cd水平下,小麦幼苗生长及Cd在小麦幼苗体内积累的变化。结果表明,营养液中加入硅可缓解小麦幼苗的镉毒害症状,增加小麦的生物量。提高溶液中的S i浓度可降低小麦根、茎、叶的Cd含量,降低幅度为叶>茎>根,营养液中的S i水平愈高,小麦Cd含量降低程度愈大,但高Cd水平下S i的作用减弱。从整株看,S i能减少小麦镉的积累量,且能抑制低镉处理(0,5μmol/L)下Cd向地上部运转,但高Cd条件下S i的抑制作用亦减弱,当营养液中的Cd浓度为10μmol/L时,S i有促进Cd向小麦地上部运转的趋势。

Solution culture was conducted to investigate the influence of Si on Cd toxicity and Cd accumulation in wheat plants. Si application significantly alleviated the toxicity of Cd to wheat, decreased Cd content in the leaves, stem and roots, and increased the biomass of the plants. The alleviation of Si on Cd content increased with Si concentration in the nutrient solution. However, with high Cd concentration in the solution, such an alleviating effect decreased. Si supplementation decreased Cd accumulation of the whole plants and inhibited the transfer of Cd from the root to the shoot in the low Cd treatment （0 and 5 μmol/L}. Such an effect decreased with higher concentration of Cd. With Cd at 10μmol/L in the solution, the addition of Si tended to promote the transfer of Cd from the root to the shoot of the plants.