尾巨桉幼苗对低温胁迫的生理生化反应

The physiological and chemical changes of Eucalyptus uorphylla×E. grandis seedlings stressed by low temperature

以尾巨桉无性系幼苗为材料，研究了低温胁迫对其生理生化的影响。试验结果表明，3℃低温胁迫对尾巨桉幼苗的电解质渗出率，随着胁迫持续时间的延长呈逐渐上升的趋势；叶绿素a的含量、叶绿素b的含量及叶绿素总量均随胁迫时间的延长而呈下降的趋势；SOD酶活性随胁迫时间呈先上升（1～3d）而后下降（3～9d）；可溶性糖的含量随低温胁迫时间的延长而随之上升。

The physiological and chemical changes of Eucalyptus uorphylla ×E. grandis seedlings stressed by low temperature were studied in this paper. The results indicated that electrolytic leakage rate of Eucalyptus uorphylla × E. grandis seedlings increased with 3℃ cold stress, and the longer duration it was, the more it increased. The longer stress it was, the less the contents of chlorophyll a, b and a ＋ b got. But the SOD activity of Eucalyptus uorphylla x E. grandis seedlings increased within 1 - 3 days, and decreased in 3 - 9 days after the stress. The soluble sugar of Eucalyptus uorphylla × E. grandis seedlings was increased immediately under low temperature stress.