高温胁迫下两种藓类植物过氧化物酶活性的变化

在不同的高温胁迫条件下 ,对湿地匍灯藓 (Plagiomnium acutum)和大羽藓 (Thuidium cymbifolium)过氧化物酶 (POD)活性及其与处理时间和处理温度的关系进行了初步研究。结果表明 ,在一定的温度范围内 ,随着温度的升高 ,POD活性增加 ,二者成线形关系。在一定温度条件下 ,一般随着处理时间的延长 ,POD活性增加。但是当超过一定的温度 (4 5～ 5 0°C)以及一定的处理时间 (4～ 6h) ,POD活性有所下降。结果还表明 ,湿地匍灯藓的POD活性显著高于大羽藓。而且在高温胁迫下 ,湿地匍灯藓 POD活性变化比大羽藓活跃 ,其变化幅度也比大羽藓大。

Effect of high temperature stress on the activity of peroxidase of two species of mosses

The effect of high temperature stress on the activity of peroxidase(POD)in Plagiomnium acutum(Lindb.)T. Kop. and Thuidium cymbifolium(Doz. & Molk.)Doz. & Molk. were studied. The activity of POD increased with the severity of higher temperature stress. A linear correlation was found between the changes of enzyme activity with the temperature. Beyond 45～50 °C,the enzyme activity decreased. In natural condition(25 °C),enzyme activity nearly unchanged. In 35～40(45) °C,the enzyme activity increased with the time of high temperature stress. In 45～50 °C,from 0 5 h to 4 h,the enzyme activity increased with the time of high temperature stress. Four hours later,the enzyme activity decreased. The results also showed that the POD activity of Plagiomnium acutum was stronger markedly than that of Thuidium cymbifolium.