镉、锌、铜胁迫对向日葵早期幼苗生长的影响  

Effects of Cadmium,Zinc and Copper-induced Stresses on the Early Seedling Growth of Sunflower(Helianthus annuus L.)

作　　者：殷恒霞[1,2] 李霞[2] 米琴[1] 王文颖[1] 张文胜[2] 徐进[2] 

机构地区：[1]青海师范大学生命与地理科学学院,西宁810008 [2]中国科学院遗传与发育生物学研究所农业资源研究中心,石家庄050021

出　　处：《植物遗传资源学报》2009年第2期290-294,299,共6页Journal of Plant Genetic Resources

基　　金：中国科学院知识创新工程青年人才领域前沿项目(0707013603)

摘　　要：分析了3种重金属离子(Cd2+、Cu2+、Zn2+)对向日葵种子胚根伸长和早期幼苗生长的影响。结果表明,3种重金属离子对向日葵胚根伸长的抑制作用依次为:Cd2+>Cu2+>Zn2+。3种重金属胁迫明显降低了幼苗生长和叶绿素含量,并显著提高了H2O2水平。其中Cd2+胁迫引起幼苗H2O2爆发高于Cu2+和Zn2+胁迫。进一步分析植株抗氧化系统的变化发现,随着重金属离子浓度的增加,向日葵幼苗酶类抗氧化物质SOD和CAT的活性表现为先增加后降低的趋势;重金属胁迫提高了非酶类的抗氧化物质脯氨酸和GSH的含量。其中Cd2+和Zn2+胁迫对脯氨酸含量变化的影响大于Cu2+胁迫;而Cu2+胁迫对GSH含量变化的影响大于Cd2+和Zn2+胁迫。Heavy metals have different effects on seed germination and early seedling growth of plants. Toxicity of three types of heavy metal ions （ Cd^2 ＋ , Cu^2 ＋ and Zn^2＋ ） on the initial growth of sunflower were investigated. The results showed that all heavy metals were toxic to sunflower, and the toxicity order to primary root elongation was Cd^2＋ 〉 Cu^2＋ 〉 Zn^2＋ Heavy metal stress significantly decreased the seedling growth and chlorophyll content, and increased the H2O2 level. Cadmium-induced H2O2 burst was higher than copper and zinc stresses. The activities of antioxidative enzymes （SOD and CAT） increased rapidly and then decreased during heavy metal stresses. In addition, heavy metal treatments significantly induced accumulation of proline and GSH. Cd^2＋ and Zn^2＋ stresses induced higher proline accumulation than that of Cu^2＋ stress; whereas, Cu^2＋ stress resulted in higher GSH level in seedlings than Cd^2＋ and Zn^2＋ stresses.

关 键 词：重金属胁迫 向日葵 幼苗生长 脯氨酸 

分 类 号：S565.5[农业科学—作物学]