硒对镉胁迫下水稻幼苗生长及生理特性的影响

Effects of Se on growth and some physiological characteristics of rice seedling under Cd stress

采用溶液培养 ,研究不同浓度的硒和镉处理对稻苗的株高、叶片干重、叶绿素、还原糖、叶片丙二醛含量以及保护酶 SOD、POD、CAT活性的影响。结果表明 ,镉胁迫下稻苗矮化 ,镉毒害使叶片失绿 ,干重降低 ,还原糖含量下降 ,叶片 MDA含量增加 ,POD活性增强 ,而 SOD、CAT活性降低 ;硒可减轻镉对水稻的毒害 ,表现为 :减轻镉胁迫对株高增加的抑制 ,提高叶绿素含量 ,增加叶片干物质积累 ,提高叶片还原糖含量 (Cd0 .5 mg/ L加 Se 0 .1 0～ 0 .5 0 mg/ L例外 ) ,降低 MDA含量与 POD活性 ,提高 SOD。

The nutrient solution culture experiment was conducted to study physiological effects of Se on the plant height,chlorophyll, dry weight and reducing sugar content of leaves, malon dialdehyde concentration and activities of superoxide dismutase(SOD), catalase(CAT)and guaiacol peroxidase(POD)in rice( Oryza sativa L.)seedling under Cd stress. The results indicated that plants under Cd stress without Se supply showed wilt, chlorosis, necrosis in leaves and black in roots, decreased in biomass, SOD and CAT activities of leaves and increease in seedling height, malondialdehyde concentration and POD activities in leaves. The addition of Se to solution with Cd could increase the dry matter weight of leaves, retard the inhibition of Cd to the increase of seedling height and alleviate the Cd toxicity, increase chlorophyll and reducing sugar content(except Cd 0 5 mg/L plus Se 0 10～0 50 mg/L), decrease MDA concentration and POD activities, enhance SOD and POD activities in leaves.