常绿阔叶灌木富贵草越冬过程中抗寒性生理指标的动态变化

Dynamic Changes of Physiological Indexes Related to Cold Resistance in Evergreen Broad-leaved Shrub Pachysandra terminalis During Winter

以常绿阔叶灌木富贵草5a生扦插苗为试材,研究其在越冬过程中叶片相对电导率、MDA含量、保护酶活性、渗透调节物含量的动态变化,以探究富贵草在引种地的抗寒性生理特征。结果表明:随田间气温的自然变化,富贵草叶片相对电导率和MDA含量先增加后减少;SOD、POD活性也基本遵循先上升后下降的变化规律,在日最低气温降至最低时活性均达到最大值;脯氨酸、可溶性糖含量均先上升后下降,在低温胁迫加剧时脯氨酸迅速积累,在气温回升逆境解除时含量迅速降低至较低水平。整个越冬过程中,各抗寒指标对气温自然变化的动态响应说明富贵草具有很好的抗寒生理基础,是长春等寒冷地区极具开发应用潜能的常绿阔叶植物。

Taking 5-year-old cuttage seedlings of evergreen broad-leaved shrub P. terminalis as test materials,dynamic changes of relative conductivity, MDA content, SOD activity,POD activity,proline content and soluble sugar content were investigated,the physiological characteristics of cold resistance of P. terminalis during winter were studied. The results showed that with the variation of natural temperature, relative conductivity and MDA content increased first and then decreased;the activity of SOD and POD probably followed the regularity that increased first and then decreased,and the activities were the highest when daily minimum air temperature reached the lowest during winter; proline content and soluble sugar content increased first and then decreased,proline accumulated rapidly with the strengthened chilling stress and decreased markedly when the climate was warmer. In the overwintering period, the dynamic response of the above indexes to the variation of natural temperature showed that P. terminalis had good physiological basis to resist low temperature,it was an evergreen broad bush that equipped with large potential of development and utilization in Changchun and other places where the air temperature was very low in winter.