菖蒲幼苗对Cd胁迫的响应及其Cd富集能力分析

研究了菖蒲（Acorus calamus L．）幼苗对不同浓度Cd胁迫的响应及其Cd富集能力。结果表明，随Cd浓度的提高（0～25mg·L^-1），菖蒲幼苗的株高、根长、干质量、叶绿素含量和对Cd的耐性指数均逐渐下降，脯氨酸含量逐渐升高；各处理组的SOD和POD活性均高于对照，且以15mg·L^-1Cd处理组最高。随胁迫时间延长（1—10d），叶绿素含量持续下降，而SOD和POD活性及脯氨酸含量则先升高后下降。菖蒲幼苗体内Cd含量随Cd浓度的提高而增加，根系对Cd的富集能力高于地上部分。在Cd胁迫条件下，菖蒲幼苗对Cd的转移系数小于1，根系对Cd的滞留率为89．5％-93．9％，表明菖蒲幼苗根系对Cd有较强的滞留作用和富集能力。

Analyses on responses of Acorus calamus seedling to Cd stress and Cd accumulation ability

The responses of Acorus calamus L. seedling to Cd stress with different concentrations and the Cd accumulation ability were studied by the water culture method. The results showed that with the increasing of Cd concentration （ 0 - 25 mg · L^-1 ） , gradually, plant height, root length, dry weight, chlorophyll content and the tolerance index to Cd of A. calamus seedling decreased, the proline content increased, and the activities of SOD and POD were all higher than that of the control and the highest was 15 mg · L^-1 Cd treatment group. With the Cd stress time prolonged （1 -10 d） , the chlorophyll content decreased and the proline content and the activities of SOD and POD increased firstly and then decreased. The Cd content in A. calamus seedling increased with the rising of Cd concentration, and the Cd accumulation ability of root was higher than that of the above-ground part, Under Cd stress condition, the biological transfer coefficient of A. calamus seedling to Cd was less than one and the Cd retention rate in root reached 89.5% - 93, 9% , which indicated that the root of A. calamus seedling has stronger retention action and accumulation ability to Cd.