盐和重金属复合胁迫对翅碱蓬萌发与生长的影响及调控措施

为探究Zn、Cu与盐复合胁迫对翅碱蓬(Suaeda salsa)萌发生长的影响机理及其调控措施，以翅碱蓬为研究对象，采用水培试验方法，测定Zn、Cu和盐复合胁迫条件下翅碱蓬种子发芽率、萌发速率和幼苗渗透调节物质含量等指标，分析1.5 mg/L吲哚乙酸(IAA)、100 mg/L赤霉素(GA)和0.3%硝酸钾(KNO₃)处理对Zn、Cu与盐复合胁迫条件下翅碱蓬萌发与生长的影响。结果表明：(1) Zn、Cu与高盐复合胁迫极显著降低翅碱蓬种子的发芽率，中高浓度的Zn、Cu与盐复合胁迫极显著降低翅碱蓬种子的萌发速率，Zn、Cu和盐复合胁迫对翅碱蓬种子的萌发生长影响表现为低促高抑效应，影响因子间存在明显的协同效应；(2)Zn、Cu和盐复合胁迫条件下，随着盐浓度的升高，翅碱蓬幼苗体内过氧化氢酶(CAT)、过氧化物酶(POD)和超氧化物歧化酶(SOD)3种抗氧化酶活性呈先升高后降低的变化趋势，Zn、Cu和高盐复合胁迫使翅碱蓬幼苗体内丙二醛(MDA)含量增加近2.5倍；(3)1.5 mg/L IAA溶液浸种12 h可显著提高Zn、Cu与高盐复合胁迫条件下翅碱蓬种子的发芽率和萌发速...

Effects of combined stress of salt and heavy metals on germination and growth of Suaeda salsa and regulation measures

To explore the influence mechanism and regulation measures of the combined stress of Zn, Cu, and salt for the germination and growth of Suaeda salsa, Suaeda salsa was taken as the research object of this paper. Taking the method of hydroponic experiment, the germination percentage, germination rate and osmotic adjustment substance content of Suaeda salsa seeds under the combined stress of Zn, Cu and salt were determined. The effects of 1.5 mg/L indoleacetic acid (IAA), 100 mg/L gibberellin (GA) and 0.3% potassium nitrate (KNO₃) on the germination and growth of Suaeda salsa under the combined stress of Zn, Cu and salt were studied. The results showed that: (1) the combined stress of Zn, Cu, and high concentration salt could significantly reduce the germination percentage of seeds of Suaeda salsa. The combined stress of Zn, Cu, and salt with the medium and high concentrations could significantly inhibit the germination rate of seeds of Suaeda salsa. The effect of Zn, Cu and salt combined stress on the germination and growth of Suaeda salsa seeds showed the effect of low concentration promotion and high concentration inhibition. There were obviously synergistic effects among the influencing factors. (2)The activity of catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD) in Suaeda salsa seedlings increased first and then decreased with the increase of salt concentration under the combined stress condition of the treatment of Zn, Cu, and salt. The content of malondialdehyde (MDA) in Suaeda salsa seedlings increased by nearly 2.5 times under the combined stress condition of Zn, Cu, and high concentration salt. (3)The 1.5 mg/L IAA solution for 12 h could significantly increase the germination percentage and germination rate of seeds under the combined stress of Zn, Cu, and excess salt, reduce the MDA content and significantly enhance the activity of POD and CAT, thereby reducing the damage of the combined stress to Suaeda salsa. It is suggested that under the combined stress of Zn, Cu and high salt, seeds of Suaeda salsa should be soaked in 1.5 mg/L IAA solution for 12 hours before replanting in coastal degraded wetland to improve the ecological restoration efficiency of Suaeda salsa wetland.