本文用三种自旋标记物5NS、12NS和16NS及荧光偏振探剂DPH~1分别对四种抗冷与不抗冷水稻线粒体膜流动性进行了比较。实验结果表明,抗冷水稻品种线粒体膜脂不同层次的流动性都大于不抗冷水稻品种,而抗冷或不抗冷水稻品种之间的线粒体膜的流动性则差异不大。用DPH比较不同抗冷性程度水稻线粒体膜流动性也得到相似的结果,即抗冷程度越弱,膜的流动性越小。这些结果表明,水稻线粒体膜流动性与它们的抗冷性具有一定的相关性。这提示测定植物线粒体膜的流动性可能为鉴定农作物的抗冷性提供一些生物物理指标。 In this paper, three kinds of spin labels 5NS, 12NS and 16NS and DPH ~ 1 were used to compare the fluidity of mitochondrial membranes of four cold-resistant and non-cold-resistant rice, respectively. The experimental results showed that the fluidity of mitochondrial membrane lipid of cold-resistant rice varieties was higher than that of non-cold-resistant rice varieties, while the mobility of mitochondrial membrane between cold-resistant and non-cold-resistant rice varieties was not different. DPH was used to compare the mitochondrial membrane fluidity with different degrees of chilling tolerance. Similar results were obtained, ie, the weaker the degree of chilling resistance, the smaller the membrane mobility. These results indicate that there is a certain correlation between the mitochondrial membrane fluidity and their cold resistance in rice. This suggests that determining the fluidity of plant mitochondrial membranes may provide some biophysical indicators for identifying the chilling resistance of crops.