高温胁迫过程中欧洲报春叶片抗氧化酶活性的变化

Dynamic changes of antioxidant enzymes activity in Primula vulgaris Huds.'LIRA' under heat stress

为研究报春属植物在高温胁迫时抗氧化系统的反应,分别以营养生长期和花期的欧洲报春‘里拉’为试材,观察在42℃胁迫过程中叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性的变化。结果表明,在高温胁迫下,叶片的3种抗氧化酶活性变化大致呈现先升高后下降的趋势,并在胁迫8～10h后保持较低水平。营养生长期的叶片SOD和POD活性变化趋势与花期的基本一致,但前者抗氧化酶活性变化幅度高于后者。这说明,欧洲报春‘里拉’营养期的叶片比花期的叶片更耐高温,在42℃下连续胁迫8～10h可能会对叶片产生不可逆的伤害。

To study the changes of Primula antioxidant system under high temperature stress, the activitis of superoxide dismutase （SOD）, peroxidase （POD）, catalase （CAT） were measured at 42 ℃ at vegetative growing stage and flowering stage of Primula vulgaris Huds. ＇LIRA＇ leaves. The results showed that the activities of three antioxidant enzymes firstly increased and then lessened, and then kept in lower level after 8-10 h at 42 ℃. The change trend of SOD and POD activitis at vegetative growing stage was almost same as that at flowering stage, but the range of former is larger than that of the latter. These results demonstrated that leaves at vegetative growing stage of Primula vulgaris LIRA had higher heat-resistance than that at flowering stage, and the continuous stress is most likely to cause irreversible injury on leaves of this plant at 42 ℃ for 8-10 h.