Abstract:

Four wild Pennisetum alopecuroides germplasms were treated with different cadmium concentrations (0, 10, 20, 50, 100, 200 mg·kg^-1) at seedling stage in greenhouse. The antioxidant enzyme activities, Cd²⁺ accumulation, and cadmium-tolerance of the four germplasms were analyzed by the evaluation of growth parameters. The results showed that the survival rates of the four germplasms were gradually reduced with the increase of Cd²⁺ concentration. However, the plant heights, tillering numbers, shoot and root biomasses of tested germplasms had no significant difference compared to controls. The material of P4 treatment was more tolerant to Cd toxicity than others. The SOD and CAT activities of the four germplasms increased and the POD activities changed irregularly with the increase of Cd²⁺ concentration. The material of P1 had the strongest cadmium absorption and accumulation ability compared with others when Cd²⁺ concentration was 200 mg·kg^-1, and it will have a good prospect in the restoration of cadmium-contaminated soil.

Key words: Cd, Pennisetum alopecuroides L., Growth, Antioxidases activity, Cd accumulation

摘要：

采用温室盆栽试验,对4份野生狼尾草(Pennisetum alopecuroides)材料进行不同浓度镉(Cd)(0,10,20,50,100,200 mg·kg^-1)胁迫处理,通过对苗期生长指标、抗氧化酶(SOD,POD,CAT)活性、地上部与根的Cd²⁺积累量等指标的测定与分析,对4份材料的耐Cd性与Cd富集能力进行研究.结果表明:随着Cd²⁺浓度的升高,4份材料的存活率呈现逐渐降低的趋势,而株高、分蘖数、地上与地下生物量与对照相比无显著变化,SOD与CAT活性均呈现逐渐升高的趋势,POD活性则呈现无规律的波动性变化,材料P4耐Cd性最强.当Cd²⁺浓度为200 mg·kg^-1时,材料P1对Cd的吸收富集能力最强,在Cd污染土壤的修复上具有较好利用前景.

关键词: 镉, 狼尾草, 生长, 抗氧化酶活性, Cd积累量