以福鼎大白为材料,通过钙过量处理诱导出茶树荧光性绿斑病,研究茶树荧光性绿斑病叶膜系统损伤、电渗率以及与膜透性有关的渗透调节物质和活性氧酶清除系统的变化。研究结果表明:茶树荧光性绿斑病叶的细胞质膜以及叶绿体、线粒体、内质网、液泡的膜系统均遭到不同程度的损伤,随着病害程度加重,丙二醛、电解质渗透率逐渐升高;与此同时可溶性糖、可溶性蛋白、脯氨酸等渗透调节物质含量也逐渐升高,超氧化物歧化酶、过氧化物酶活性在发病初期显著升高,后期降低,但活性均高于对照。以上结果说明:茶树荧光性绿斑病叶在发病期间虽然启动了活性氧清除的膜保护机制,但仍然无法逆转膜系统损伤的发生。
In order to probe the membrane structure and its related physiological changes in the tea leaves with fluorescent green spot disease, the diseased tea leaves were picked from the Fu Ding Da Bai tea plant cultivated in the nutritional solution with excessive calcium, and cellular membrane system was observed by transmission electron microeope, the electrolytic leakage, the contents of osmosis and the antioxidative enzyme activities of diseased tea leaves were determined. The results showed that the plasma membrane, chloroplast membrane, mitochondrion membrane, endoplasmic reticulum membrane and vacuole membrane in diseased tea leaves were damaged in different degree. With the extending of stress and the disease, the malondialdehyde (MDA) content and the electrolytic leakage increased, meanwhile the soluble sugar content, the soluble protein content and the free proline content increased rapidly in the diseased tea leaves. The activity of superoxide dismutase (SOD), peroxidase (POD) increased significantly at the initial stage of the diseased tea leaves, subsequently decreased, but their activities were higher than normal tea leaves. On the basis of above results, although the antioxidative enzyme activities were increased, it was incapable of reversing the damage of membrane system of the diseased tea leaves.