Cu^(2+)、Zn^(2+)单一及复合胁迫对木槿种子萌发及抗氧化特性的影响

Effects of Cu^(2+) and Zn^(2+) Single and Combined Stress on Seeds Germination and Antioxidant Characteristics of Hibiscus syriacus L.

以木槿种子为试验材料,通过3种重金属胁迫处理,测定了不同质量浓度的铜、锌单一胁迫及铜锌复合胁迫对种子发芽指标、生长指标、抗氧化特性的影响。结果表明:木槿种子的发芽率、发芽势、发芽指数随着3种胁迫处理液质量浓度的提高呈先升后降的趋势。胚根长度随着3种胁迫处理液质量浓度的提高呈逐渐下降的趋势。回归方程预测,木槿种子铜单一胁迫的半致死质量浓度和极限质量浓度最低,锌单一胁迫的半致死质量浓度和极限质量浓度最高,铜锌复合胁迫的半致死质量浓度和极限质量浓度居于两者之间。木槿幼苗的丙二醛(MDA)质量摩尔浓度与处理液质量浓度呈正比。随着3种胁迫处理液质量浓度的提高,过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性呈先升后降的趋势。隶属函数法综合分析,木槿种子对3种重金属胁迫的耐受能力依次为锌单一胁迫、铜锌复合胁迫、铜单一胁迫。

The seeds of Hibiscus syriacus L. were treated with three kinds of heavy metals, and the effects of different mass concentrations of copper, zinc single stress and copper and zinc compound stress on germination index, growth index and antioxidant characteristics of seeds were measured. The germination rate, germination potential and germination index increased firstly and then decreased with the increase of the mass concentration of three stress treatment solution. Radicle length decreased gradually with the increase of the mass concentration of three stress treatment solution. The regression equation predicted that the semi-lethal mass concentration and limit mass concentration of copper under single stress were the lowest, while that of zinc under single stress were the highest, and that of copper and zinc under combined stress werein the middle. The malondialdehyde(MDA) molality of seedlings was proportional to the mass concentration of treatment solution. The peroxidase(POD) and superoxide dismutase(SOD) activities increased firstly and then decreased with the increase of the mass concentration of three stress treatment solution. According to the comprehensive analysis of subordinate function values, the tolerance of seeds to three kinds of heavy metal stress was followed by zinc single stress, copper and zinc combined stress, and copper single stress.