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紫外线B对水稻叶组织中活性氧代谢及膜系统的影响

晏斌, 戴秋杰

江苏省农业科学院农业生物遗传生理研究所.江苏,南京 210014

摘要

增强UV-B处理下,水稻叶片的O~(.)_(2)净产生速率、H_(2)O_(2)和MDA含量以及膜透性都显著增加,敏感性弱的品种O~(.)_(2)净产生速率和膜伤害程度较低。在UV-B处理初期活性氧清除系统的水平增高,但随着处理时间的延长,SOD、CAT和AP活性以及ASA含量降低,其中AP和SOD活性的下降最为明显,而敏感性弱的品种SOD活性始终高于敏感性强的品种。处理14d后去掉UV-B,再经则14d上述各指标均恢复到与对照相近的水平。根据这些结果推测,水稻的UV-B伤害可能主要是由于SOD活性的降低而导致O~(.)_(2)增生和膜脂过氧化。

关键词： 水稻; 紫外线B; 膜透性; 膜脂过氧化 ; 活性氧代谢

Effects of ultraviolet-B radiation on active oxygen metabolism and membrane system of rice leaves

Yan Bin, Dai Qiujie

The Institute of Agrobiological Genetics and Physiology, Jiangsu Academy of Agricultural Sciences. Nanjing 210014, Jiangsu

Abstract

Two rice cultivars (IR74 and Dular) were grown in a greenhouse for ten days and then treated with four levels of UV-B (0.0, 6.0, 13.0, 19.1 kJ m~(-2) d~(-1)) for 28 days in a glasshouse. UV-B radiation caused significant increased in electrolyte leakage, malindialdehyed (MDA) content and the net rate of O_(2) generation. These increases were greater in the sensitive cultivar Dular than in the less-sensitive cultivar IR74 under high radiation (13.0 and 19.1 kJ m~(-2) d~(-1)) and long UV-B exposure (28 days). The extents of the changes in O_(2) and MDA content were greater than those of electrolyte leakage and H_(2)O_(2) content. Ascorbate peroxidase activity was significantly reduced and other antioxidants (superoxide dismutase, catalase, ascorbic acid and glutathione) were enhanced during short exposure to UV-B radiation (14 days). SOD activity, however, was reduced after 14 day treatment. The less-sensitive cultivar retained a higher SOD activity than the sensitive one under high radiations. The parameters described above returned to levels similar to those of the control (0.0) after UV-B radiation (13.0) had been stopped for 14 days. Based on these results, it is deduced that UV-B injury to membrane may be correlated to excessive production of O~(.)_(2) which induces an increase in lipid peroxidation, while O~(.)_(2) accumulation may be caused by the inhibition of SOD. The varietal difference in UV-B sensitivity of rice cultivars may involve the difference in SOD level, which affects the rate of breakdown of O~(.)_(2).

Key words: Dryza sativa L;Ultraviolet-B;Membrane permeability;Lipid peroxidation;Active oxygen metabolism

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引用本文：

晏斌, 戴秋杰. 紫外线B对水稻叶组织中活性氧代谢及膜系统的影响[J]. 生理学报 1996; 48 (4): .

Yan Bin, Dai Qiujie. Effects of ultraviolet-B radiation on active oxygen metabolism and membrane system of rice leaves. Acta Physiol Sin 1996; 48 (4): (in Chinese with English abstract).