摘要
为探究植物对重金属铅(Pb)的积累和耐性,以锦葵科(Malvaceae)植物蜀葵(Althaea rosea Cavan.)为材料,研究了不同Pb浓度(0、50、100、200、500 mg·kg-1)处理对蜀葵叶片抗氧化酶活性及生理特性的影响。结果发现:蜀葵对于重金属Pb胁迫有较强的耐受性,低浓度Pb处理促进蜀葵地上生物量的积累,抑制了蜀葵根的生长,且根为主要积累Pb的部位;Pb浓度的增加导致相对叶绿素含量(SPAD)降低,过氧化氢(Hydrogen peroxide,H2O2)、超氧阴离子(Superoxide anion,O-2·)、丙二醛(Malondialdehyde,MDA)含量及电解质外渗率(Electrolyte leakage,EL)增加;Pb浓度为100 mg·kg-1时,超氧化物歧化酶(Superoxide dismutase,SOD)、过氧化物酶(Peroxidase,POD)、过氧化氢酶(Catalase,CAT)、抗坏血酸过氧化物酶(Ascorbate peroxidase,APX)活性比对照分别增加了5.6%、29.36%、22.48%和54.19%。研究表明,蜀葵可以通过调节自身的生理生化机制来适应Pb胁迫环境,可用于Pb污染地区的土壤修复。
In the present study, Althaea rosea Cavan. was exposed to different concentrations of lead（Pb）（0, 50, 100, 200, and 500 mg·kg-1）for 70 d to evaluate its morphological, physiological, and biochemical responses. The results showed that Pb stress inhibited the growth of different parts of A. rosea, but lower concentrations stimulated an increase in biomass of the shoots. In addition, the accumulation of Pb was found to increase in a concentration-dependent manner, with a maximum of 13.44 μg·g-1in the shoots and 17.72 μg·g-1in the roots at 500mg·kg-1. Leaf electrolyte leakage, hydrogen peroxide, superoxide anion, and malondialdehyde contents accumulated significantly as the concentration of Pb increased. In contrast, the content of chlorophyll decreased with increasing Pb concentration. In addition, the activities of antioxidant enzymes increased under lower Pb levels, but decreased at higher Pb levels. At the Pb concentration of 100 mg·kg^-1, the activity of superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase increased by 5.6%, 29.36%, 22.48%, and 54.19%, respectively.This study signifies that A. rosea can adjust its own physiological and biochemical mechanisms to adapt to Pb stress, thus A. rosea can be used for soil remediation in contaminated areas.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2017年第9期1746-1752,共7页
Journal of Agro-Environment Science
基金
科技部科技基础性工作专项(2011FY110300)~~
关键词
铅胁迫
蜀葵
抗氧化酶
积累特性
植物修复
lead stress
Althaea rosea Cavan
antioxidant enzymes
accumulation characteristics
phytoremediation
