Effect of Lead Stress on Growth Characteristics and Physiological Indexes of Alternanthera philoxeroides

[Objective] The paper aimed to discuss effects of different concentrations of lead stress on Alternanthera philoxeroides growth and physiological indices,to explore phytoremediation methods for removal of lead pollution. [Method] A. philoxeroides in water culture was treated with different concentration of lead,and then,its external injury was observed,its growth and physiological indexes were measured. [Result] A. philoxeroides biomass and chlorophyll content decreased; conductivity and malonaldehyde （MDA ） content were increased; the SOD,POD and CAT activities showed a trend of first increase and then decrease with increase in concentration of lead stress. [Conclusion] With increase in lead concentration,the cell membrane permeability increased and MDA had a higher accumulation,antioxidant enzymes activity decreased,the normal oxidative metabolism of A. philoxeroides was severely affected,leading it to wilt.

铅胁迫对空心莲子草生长和生理指标的影响

[目的]研究铅胁迫对空心莲子草生长和生理指标的影响,探究重金属铅污染的植物修复方法。[方法]采用不同浓度铅胁迫水培空心莲子草后,观察其外伤症状,并测定其生长指标和生理指标。[结果]随着铅胁迫浓度的增加,空心莲子草生物量和叶绿素含量逐渐降低,茎叶电导率和丙二醛含量持续增加,而SOD、POD和CAT活性则先增加后降低。[结论]当铅浓度不断增加时,空心莲子草茎叶细胞膜透性增大,丙二醛含量高度积累,抗氧化酶系统活力下降,正常氧化代谢受到严重影响,导致植株枯萎。