低温胁迫对桉树代谢的影响

Effects of Chilling Stress on the Metabolism of Eucalyptus

以5种桉树幼苗为材料,测定了低温胁迫对其生理生化等的影响。试验结果表明:随温度的降低几种桉树幼苗的相对电导率和游离脯氨酸含量与对照相比都呈升高趋势;总体上可溶性蛋白质含量与对照相比有所下降;可溶性糖含量与对照相比呈上升趋势,但在0～-3℃之间表现出下降的趋势,可溶性糖的下降率与桉树的抗寒性有关;超氧化物歧化酶活性呈现先降低后升高再降低的趋势,但总体上,随着温度的降低,酶活性是下降的;而膜脂过氧化的主要产物丙二醛,随着温度的降低呈增加的趋势。

The effect of low temperature stress on the physiology and biochemistry of five species of Eucalyptus was tested. The results showed that compared with the control, the relative conductance rate and the content of free praline increased under low temperature. As a whole, the content of protein decreased with the decreasing of low temperature. The soluble sugar content increased under low temperature, but displayed a decreasing trend at 0～-3℃. The falling rate of soluble sugar was related to the cold-tolerance of eucalyptus. The activity of SOD showed the trend of declining-rising-declining with the decreasing of low temperature, but as a whole, the SOD activity was declining. The content of MDA increased with the decrease of temperature, which indicated that the membrane lipid peroxidization was enhanced under low temperature.