《植物生理学报》 2015, 51(11): 1969-1974

重金属镉(Cd)胁迫对水芹生长及生理特性的影响

张静, 赵秀侠, 汪翔, 卢文轩^*

安徽省农业科学院水产研究所, 合肥230031

通信作者：卢文轩；E-mail: ahfishery@163.com；Tel: 0551-65147122

摘　要：

采用水培试验, 在不同镉(Cd)浓度条件下, 研究镉在水芹各个器官内的积累及生长规律, 同时检测镉对水芹的生理生化指标的影响, 包括水芹根部细胞的超微结构、叶绿素含量、可溶性蛋白含量、根系活力指标。结果表明, 在低浓度Cd²⁺处理下, 实验组与对照组株高和根数无区别(P>0.05); 高浓度处理下, 水芹株高和根数都显著减少, 鲜重生物量也明显降低, 地上生物量与地下生物量比值升高。当Cd²⁺达到2 mg•L^-1时根部细胞逐渐失去原有基本形态, 胞浆内容物密度增大, 细胞壁部分出现断裂等特征。根、茎和叶三种器官镉元素含量随着Cd²⁺浓度升高而增加, 当 Cd²⁺浓度为10 mg•L^-1时, 根、茎和叶中镉元素含量达到最大, 分别为(422.726±0.023)、(78.645±0.012)和(49.118±0.041) mg•kg^-1; 吸收效率和转运效率随着Cd²⁺浓度升高而逐渐增高, 富集系数在Cd²⁺浓度为1 mg•L^-1时达到最大, 随后呈递减趋势。此外, 在高浓度Cd²⁺的作用下, 叶绿素总量、叶绿素a和可溶性蛋白总体均呈现下降趋势。

关键词：水芹; 镉; 富集系数; 超微结构; 根

收稿：2015-08-14   修定：2015-11-10

资助：安徽省院士工作站项目(科人[2014] 12号)、院长青年基金项目(14B0533)、院创新团队项目(11c0505)和省工程中心项目(皖科[2010]123号)。

Effects of Cadmium Stress on the Growth and Physiological Property of Oenanthe javanica

ZHANG Jing, ZHAO Xiu-Xia, WANG Xiang, LU Wen-Xuan^*

Fisheries Research Institute, Anhui Academy of Agricultural Sciences, Hefei 230031, China

Corresponding author: LU Wen-Xuan; E-mail: ahfishery@163.com; Tel: 0551-65147122

Abstract:

A solution culture was carried out to study growth pattern of cadmium accumulation in various organs and examined the effect of cadmium on physiological property of Oenanthe javanica, including cell ultrastructure of root, chlorophyll content and root activity in Oenanthe javanica at different concentrations of cadmium (Cd). The results showed that the treatment with low concentration of Cd²⁺ in the experimental groups and control group plant height and the number of root had no difference (P>0.05). Instead, plant height and the number of the root significantly reduced, as well as fresh weight biomass at high concentrations. In addition, aboveground biomass and underground biomass ratio value increased, indicating obvious influence on the root of Oenanthe javanica with the Cd²⁺ concentration increasing. Cell form of the root had gradually loss, cytoplasm contents density increased and part of cell wall was broken at Cd²⁺ concentration of 2 mg•L^-1. Cd content of the three organs increased in the overall trend with the Cd²⁺ concentration increasing. The maximum cadmium content of roots, stems and leaves were (422.726±0.023), (78.645±0.012) and (49.118±0.041) mg•kg^-1 at Cd²⁺ concentration of 10 mg•L^-1. The absorption efficiency and transport efficiency were gradually increased, while the concentration coefficient reached maximum at Cd²⁺ concentration of 1 mg•L^-1, then gradually decreased with the Cd²⁺ concentration increasing. Finally, the results also showed Cd²⁺ lead to a downward trend of the total chlorophyll, chlorophyll a and soluble proteins.

Key words: Oenanthe javanica; cadmium; concentration coefficient; ultrastructure; root