不同生长时期碱蓬在Pb²⁺、Cd²⁺单一及复合胁迫下的生理生化响应

Physiological and Biochemical Responses of Suaeda salsa to Pb²⁺,Cd²⁺ in Single and Combined Stress at Different Growth Stages

摘要: 由于人类活动及工业化的迅速发展，沿海滩涂湿地正在遭受前所未有的污染和破坏，其中铅、镉污染是主要的污染之一，而碱蓬有较强的重金属耐受性和耐盐性，在修复污染的同时也具有较高的经济价值。为研究不同生长时期碱蓬在Pb²⁺、Cd²⁺胁迫下的生理生化响应，采用蛭石室外培养，对碱蓬进行Pb²⁺、Cd²⁺单一及复合污染处理，结果表明：Pb²⁺、Cd²⁺单一及复合胁迫下，碱蓬幼苗期与花期的株高、超氧化物歧化酶(SOD)活性、脯氨酸(Pro)含量、丙二醛(MDA)含量均呈显著差异(P<0.05)。碱蓬在抵御外界Pb²⁺、Cd²⁺胁迫时，以SOD活性的快速响应为先，Pro的渗透调节抵御为后，MDA的无序变化实时表征植物的受损状况。总之，碱蓬对Pb²⁺、Cd²⁺的胁迫有较强的自我调节能力，具有修复Pb²⁺、Cd²⁺污染的潜力，这为进一步利用盐生植物碱蓬修复滨海滩涂等高盐碱土壤，以及抵御Pb²⁺、Cd²⁺等重金属复合污染的损伤机制研究提供了理论依据。

Abstract: Due to the rapid development of human activities and industrialization, tidal wetlands are suffering from unprecedented pollution and destruction b which lead and cadmium pollution is one of the heavy metal pollution. While Suaeda salsa has strong heavy metal tolerance, in the removal of pollution at the same time also has high economic value. In order to study the growth and physiological and biochemical responses of Suaeda salsa under different Pb²⁺ and Cd²⁺ concentration, the plant was cultured by vermiculite outdoors, single and combined pollution of Pb²⁺ and Cd²⁺ was carried out. The results showed that the plant height and contents of SOD, Pro and MDA in seedling stage and flowering stage of Suaeda salsa were significantly different. When the Suaeda salsas were responded to the Pb²⁺, Cd²⁺ single and combined stress, SOD activities responded quickly at first, Pro’s osmotic adjustment would be activated after SOD, the disorderly MDA contents real-time indicated the damaged conditions of cell membrane. In conclusion, Suaeda salsa had strong self-adjustable mechanism when under the Pb²⁺, Cd²⁺ stress treatment and which have potential for restore the Pb²⁺, Cd²⁺ pollution, which provide a theoretical basis for injury mechanism in which halophytes Suaeda salsa restore high saline areas, such as coastal wetlands and resist the heavy metals contamination.