通过土壤盆栽研究了不同浓度镉(Cd,0、2.5、50mgkg^-1)、锌(Zn,0、100、500mgkg^-1)胁迫下红树植物秋茄的幼苗体内可溶性蛋白、可溶性糖、脯氨酸、有机酸含量的变化.结果表明,Cd、Zn单一处理下,秋茄体内渗透调节物质含量随重金属浓度升高而增加;Cd、Zn复合处理对秋茄体内可溶性蛋白质含量的复合效应主要表现为协同作用:Cd的加入减弱Zn对秋茄体内可溶性糖含量的刺激作用,低Cd浓度处理TZn的加入导致可溶性糖含量增加,而高Cd浓度处理TZn的加入反而降低其含量.低浓度Zn(或Cd)的加入与土壤中Cd(或Zn)发生拮抗作用,秋茄体内脯氨酸、有机酸含量下降;高浓度Zn(或Cd)的加入与土壤中的Cd(或Zn)发生协同作用,导致渗透调节物质脯氨酸、有机酸的积累量增加,从而缓解高浓度重金属的胁迫.植物组织或部位不同,Cd与Zn浓度和比例不同,Cd、Zn之间的复合作用存在一定的差异.
Potted culture experiment was used to investigate the effects of co-contamination of Cd (0, 2.5, 50 mg kg^-1) and Zn O, 100, 500 mg kg^-1) on the contents of osmotic adjustment substances in Kandelia candel (L.) Druce seedlings. The interaction effect of Cd-Zn combined stress on the content of soluble protein was mainly mutual. The content of soluble sugar decreased with the addition of Cd when Zn concentration was 100 and 500 mg kg^-1. Low Zn concentration increased the soluble sugar content, while high Zn concentration decreased it when Cd (2.5 and 50 mg kg^-1) was added. The interaction effect of Cd- Zn combined stress with low concentration on the contents of proline and organic acid was as also mutual, and it showed antagonism at high level of the combined stress. It was suggested that the compound pollution of Cd and Zn was not simply an additive or antagonistic effect. It depended on the Cd and Zn concentrations and their combinations in soil, as well as on the different parts of the plant.