几个杨树品种低温与变温胁迫对比试验

以几种常见杨树品种为试材,在不同时期进行了低温胁迫试验,通过相对电导率测试及生长恢复情况调查,分析了不同时期低温对杨树发生冻害的影响,结果显示：在冬季树木深休眠期持续的低温对杨树具有一定的伤害,但伤害程度不大;初春树木萌动期低温对杨树伤害较大。根据此结论,进一步开展变温胁迫试验,结果显示：高温和低温的变温对不同杨树伤害较大,而且变化幅度越剧烈,造成伤害越严重。

Comparison Experiments on Stress with Low Variable Temperature on Several Varieties of Poplar

Taking several common poplar species as test materials ,experiments of low temperature stress under dif-ferent periods were conducted .Through the relative conductivity test and growth recovery investigations ,the effects of low temperature under different periods on freeze injury occurred in poplar were analyzed .Result shows that ：continued low-temperature in the period of deep dormancy for trees in the winter have certain damages on poplar ,but the damage is not high;low-temperature cause greater damages on poplar in the sprout period for trees in early spring .Based on the above conclusions ,further variable temperature stress experiments were conducted .Result shows that ：variable temperatures of high temperature low temperature cause greater damages on different pop-lar ,and the more serious changes in the amplitude ,the more serious harm .