几种沙生植物水分代谢问题探讨

Water Metabolism of Several Psammophyte

采用野外采集与室内实验相结合的方法,对磴口地区8种沙生植物的水分代谢进行了相关研究。结果表明:沙生植物的水势与抗脱水能力呈负相关,与蒸腾日变幅呈正相关,可溶性糖、盐含量对沙生植物的水势起决定作用,蛋白质含量和亲水基团的多少决定束/自比的大小。出现与无贮水组织的沙生植物中的束/自比与日蒸腾强度之间的相关性,在具贮水组织的沙生植物中未出现。叶中具贮水组织的沙生植物的蛋白氮含量与束/自比呈负相关,在无贮水组织的沙生植物中却呈正相关关系。在无贮水组织的类型中水势与束/自比的关系不明显。

By use of field collection and indoor test, the water metabolism of eight kinds of psammophyte distributed in Dengkou have been studied. The results show that there is a negative correlation between water potential and an- ti-dehydration of psammophyte, there is a positive correlation between water potential and transpiration daily varia- tion amplitude, the content of soluble sugar and salt have played a decisive role on water potential of psammophyte, and the protein content and quantity of hydrophilic group can decide the ratio of bound water to free water. The cor- relation between the ratio of bound water to free water and transpiration intensity in psammophyte without water stor- age parenchyma doesn＇ t appear in psammophyte with water storage parenchyma. There is a negative correlation be- tween the protein content and the ratio of bound water to free water in psammophyte with water storage parenchyma in leaves, which is a positive correlation in psammophyte without water storage parenchyma. There isn＇ t obvious relationship between water potential and the ratio of bound water to free water in psammophyte without water storage parenchyma.