地被菊露地越冬期间的抗寒性研究

On the cold resistance of ground-cover chrysanthemum growing in the open field during the autumn-winter

以地被菊(Dendranthema×grandiflorum Kitamura)‘紫勋章’品种为植物材料,对其在北京秋冬季自然降温过程中叶片、脚芽、根进行测定分析,并运用相关分析法对各生理指标间相关性进行分析。结果表明:在露地越冬过程中,地被菊的根系活力随温度缓慢下降;叶片、脚芽的相对含水量及根的含水量随温度降低而下降;叶片、脚芽的SOD、CAT酶活性总体呈升降趋势,POD则相反,而根的酶活性只在突然降温的短期内及1月份出现显著变化,总体受低温影响较小;叶片的可溶性糖含量显著增加,可溶性蛋白和脯氨酸含量总体呈下降趋势;脚芽和根的渗透调节物质含量总体呈升降趋势。相关分析表明,地被菊的抗寒性与相对含水量、SOD、可溶性蛋白、可溶性糖、根系活力密切相关。

The ground-cover chrysanthemum （Dendranthema X grandiflorum, Kitamura） was used as the experimental material in this study. The physiological and biochemical indexes of leaves, emergent rhizomes and roots from ＇Zi Xunzhang~ which grew in the open field during the autumn and winter in Beijing area were determined. The results showed that root activity de- creased slowly with the drop of the temperature. The relative water contents of leaves, emergent rhizomes and the water con- tent of roots decreased. The activities of SOD and CAT from leaves and emergent rhizomes increased firstly, and then de- creased. The activities of POD were in contrast. The changes of the enzyme activities of roots were little, expect in January and the periods in which the temperature dropped in suddenly. With the significant increasing of the content of soluble sugar from leaves, the contents of soluble protein and proline declined overall; and the contents of osmotic regulation substances of emer- gent rhizomes and roots increased at first and then decreased. Correlation analysis indicated that the cold resistance of ground- cover chrysanthemum ＇Zi Xunzhang＇ was related closely to SOD, soluble protein, soluble sugar and root activity.