硅对水稻幼苗铝毒的缓解效应

Effects of Silicon on Alleviating Toxicity to Rice Seedlings under Aluminum Stress

在铝胁迫处理的基础上,通过添加不同浓度的K2SiO3,研究了硅对水稻幼苗铝毒的缓释效应。结果表明,1.5 mmol/L Al3+处理对水稻幼苗根系和叶片均产生了较大伤害,根系质膜透性显著增大,光合电子传递受到限制,叶片光合作用减弱;在铝胁迫条件下,添加硅可降低根系的相对电导率,改善叶片的叶绿素荧光参数,提高净光合速率,促进铝胁迫下水稻幼苗的生长。1.0mmol/L K2SiO3处理对缓解水稻幼苗铝毒的效果较好。

The effects of silicon （Si） on alleviating the aluminum toxicity to rice seedlings were studied by adding different concentrations of K2 SiO3 under aluminum （A1） stress. The results showed that the A1 stress treatment with 1.5 mmol/L A13＋ solution had a damaging effect on the growth of roots and leaves of rice seedlings with a significant increase of the membrane permeability of roots and a great decrease of photosynthesis for the inhibition of pho-tosynthetic electron transport. Addition of 0.1 -1.5 mmol/L K2SiO3 into the 1.5 mmol/L Al3＋ solution could de- crease the relative electric conductivity of roots, improve leaf fluorescence parameters （Fo, Fm, and Fv/Fm） and increase the net photosynthetic rate, and finally enhance the growth of rice seedlings. Among all treatments, the treatment with addition of 1.0 mmol/L K2SiO3 showed the best effect on alleviating the A1 toxicity to rice seedlings under A1 stress.