高温对椰心叶甲啮小蜂保护酶系活性的影响

采用分光光度法测定椰心叶甲啮小蜂（Tetrastichus brontispae）幼虫、 蛹和成蜂经 30、 33、 36、 39、 42 ℃处理后体内 3 种保护酶活性的变化。 结果表明： （1）经不同高温处理后， 椰心叶甲啮小蜂幼虫、 蛹和成蜂体内过氧化氢酶（Catalase， CAT）活性随着温度升高而先升高后降低， 其中幼虫、 蛹体内 CAT 活性高于对照。 39 ℃为CAT 清除 H2O2 的最适温度， 高于 39 ℃则 CAT 活性受抑制。 （2）经不同高温处理后， 椰心叶甲啮小蜂幼虫体内过氧化物酶（Peroxidase， POD）活性高于对照， 蛹和成蜂体内 POD 活性低于对照。 幼虫在 33 ℃时体内 POD 活性达最大值， 之后随着温度的升高逐渐下降； 蛹和成蜂体内 POD 活性随温度的升高而升高。 （3）经不同高温处理后，椰心叶甲啮小蜂幼虫和蛹体内超氧化物歧化酶（Superoxide dismutase， SOD）活性随温度升高而升高， 其体内 SOD活性均高于对照。 成蜂体内 SOD 活性随温度升高而先升高后降低， 在 39 ℃时达到最大值， 但低于对照。

Effect of High Hemperature on the Protective Enzymes of Tetrastichus brontispae

The activity of protective enzymes in larvae, pupa and adult of Tetrastichus brontispae was determined after exposed to 30, 33, 36, 39, 42 ℃ with spectrophotometric method. The results showed that: (1) The activity of catalase （CAT） in the larvae, pupa and adults of T. brontispae after exposed to different high temperatures increased first and decreased later while temperature rising. The activity of CAT in the treated larvae and pupa of T. brontispae were higher than that of the control. 39 ℃ was the most suitable temperature at which H2O2 was scavenged by CAT, and the activity of CAT was inhibited after the temperature was higher than 39 ℃. (2) The activity of peroxidase (POD) in the larvae of T. brontispae after exposed to different high temperatures was higher than that of the control ， while that of the pupa and adult of T. brontispae were lower. The activity of POD in the larvae of T. brontispae was stimulated initially when the temperature reach to 33 ℃, and then decreased with the raise of temperature. The activity of POD in the pupa and adult of T. brontispae increased with the raise of temperature. (3) The activity of superoxide dismutase (SOD） in the larvae and pupa of T. brontispae after exposed to different high temperatures increased with the raise of temperature, and the activity of SOD were higher than that of the control. The activity of SOD in the adult of T. brontispae was the highest when the temperature reached 39 ℃ and lower than that of control. The research above layed a basis to further study the heat-tolerant mechanism of T. brontispae.