镉胁迫对盐地碱蓬二型种子幼苗生长及抗逆生理的影响

To explore the adaptation strategy and response mechanism of Suaeda salsa dimorphic seedlings under Cd stress,and to select the seed type with potential to repair Cd polluted saline soil.The seedlings growth,Cd accumulation in different organs,antioxidant enzyme specific activity and osmotic regulator contents were examined by soil culturing Suaeda salsa in Liaohe Estuary wetland with 0、0.04、0.2、0.4 and 0.8 mg?kg-1 Cd stress.The results showed that:(1)the plant height and fresh weight of black seed seedlings were more inhibited than that of brown seed seedlings under Cd stress.The root,stem and leaf biomass of brown seed seedlings were higher than that of black seed seedlings under Cd stress.(2)The antioxidative responses of SOD,POD and CAT in brown seed seedlings were stronger than those in black seed seedlings.The contents of osmotic regulator increased significantly,and the contents of soluble sugar and proline in brown seed seedlings were significantly higher than those in black seed seedlings.(3)The Cd accumulation of brown seed seedlings was higher than that of black seed seedlings,and the distribution of Cd accumulation in different organs was root>leaf>stem.(4)Cd accumulation and osmotic regulator contents had a positive correlation(P<0.01),as well as between plant growth and antioxidant enzyme activity(P<0.05).In conclusion,under different conditions of Cd pollution,brown seed seedlings had stronger Cd tolerance than black seed seedlings,and brown seed seedlings had better ability to repair Cd polluted saline soil.