重金属胁迫下桉树种子发芽与根伸长的响应与生态毒性效应研究

以南方重要造林树种邓恩桉、本沁桉、巨桉、直杆蓝桉为研究对象，采用溶液培养方法，在20d试验期中分别研究了不同质量分数的铜、锌、镉对这4种桉树种子发芽与根伸长的污染效应。结果表明，不同质量分数的铜、锌、镉对邓恩桉、本沁桉、巨桉与直杆蓝桉的种子发芽与根伸长均存在抑制效应，其中对种子的发芽具有明显的抑制性，但对种子发芽过程（发芽高峰期）影响较小。4种桉树在试验所设计的3种重金属Cu、Zn、Cd中均表现出对Cu具有较高敏感性。另外，重金属质量分数与种子发芽抑制率之间普遍存在着显著的回归关系，且对根伸长的抑制效应明显大于对种子发芽的影响，高质量分数重金属对根伸长的抑制率均达80%以上，甚至达到100%。

Eco-toxicology of Heavy Metals on the Inhibition of Seed of Eucalyptus

The ecological effects of copper，zinc and cadmium on the inhibition of seed germination and root elongation of Eucalyptus dunnii，Eucalyptus benthamii，Eucalyptus grandis，Eucalyptus labill were studied in this paper in 20 days of the trial period．Results indicated that the inhibition effects of heavy metals on seed germination and root elongation were all obvious in each concentration of heavy metals，heavy metals decreased the rate of seed germination，but these are the eucalyptus seed germination process less affected. And also，the result indicated that eucalyptus in the four tests designed by three kinds of heavy metals Cu，Zn，Cd than in the three show they are more sensitive to the Cu．In addition， the regression relationships between heavy metal concentration and the inhibition rates of seed germination and root elongation of Eucalyptus were remarkable，eucalyptus seed more sensitive to heavy metal pollution，inhibition of root elongation generally reach 100 percent，significantly higher than inhibit seed germination rate．