铅、锌诱导的高羊茅叶片过氧化物酶活性变化

Pb,Zn-induced Changes of Peroxidase Activities in Tall Fescue Leaves

采用水培方法,研究了铅、锌诱导下的高羊茅叶片过氧化物酶活性变化.结果表明:高羊茅对Pb2+、Zn2+胁迫有一定的耐受能力,低浓度(0.5 mmol/L)的Pb2+、Zn2+胁迫均会使高羊茅叶片POD活性随处理时间的延长先升高后下降,但10天时还保持在高于对照的水平;高浓度Pb2+、Zn2+胁迫POD活性无论开始是否上升,至10天时均下降至对照水平以下.试验同时表明高羊茅对Zn2+耐受能力要大于Pb2+.

Tall rescue （Festuca arundinacea Schreb. ）cultured in Hoagland nutrition solution were treated with different concentrations of Pb（NO3）2 and ZnSO4 from 0 to 8 mmol/L. After 2,4,6,8, and 10 days＇ treatment, activities of peroxidase（POD, EC 1.11.1.7） were measured. Tall rescue had tolerance to heavy meatal. POD activities in leaf extracts were increased with 0.5 mmol/L Pb^2＋ and Zn^2＋ and then decreased while time was prolonged. But POD activities with 0.5 mmol/L were higher than the control level on the tenth day. POD activities with high concentration Pb^2＋ and Zn^2＋ were lower than the control level whether they were enhanced or reduced at the beginning and were lower than the control level on the tenth day. The tolerance of tall rescue to heavy metals followed the sequence： Zn^2＋〉 Pb^2＋ .