异质性UV-B辐射下NO在活血丹光合特性中的作用研究

The Effects of NO on Photosynthetic Characteristic in Glechoma longituba under Heterogeneous UV-B Radiation

我们前期研究发现异质性UV-B辐射下NO参与克隆植物紫外吸收物和抗氧化酶活力的整合过程。光合作用在植物生长过程中十分重要,但异质性UV-B辐射下NO在克隆植物光合特性中是否发挥作用仍不清楚。本研究模拟同质(克隆分株片段均处于自然背景辐射)和异质(克隆分株一端处于自然背景辐射,另一端处于补加的UV-B辐射)UV-B辐射,以克隆植物活血丹为材料,研究异质性UV-B辐射下,NO清除剂在克隆整合提高活血丹气体交换参数和叶绿素含量中的作用。结果表明:与处于同质UV-B辐射环境相比,异质UV-B辐射下连接处理中的活血丹UV-B辐射端气体交换参数和叶绿素含量显著增加,但NO清除剂改变了这一趋势,说明NO作为信号分子在克隆植物生理整合提高了活血丹光合生理特性中发挥重要作用,有助于全面认识UV-B辐射在克隆植物生长调控中的作用,为了解异质性UV-B环境下克隆植物生理整合的机理提供理论依据。

Our research has found that NO was involved in and the activity of antioxidant enzymes among clonal plants the integration process of UV-B absorbing compounds under heterogeneous UV-B conditions. Photosynthesis played a key role in the growth process of plants, while it was unknown whether or not NO played an important role in photosynthesis of cloned plants under heterogeneous UV-B conditions. In this study, pairs of connected ramets of the stoloniferous herb Gleehoma longituba were grown under the homogeneity （both oframets received only natural background radiation） and heterogeneity of UV-B radiation （one of the ramet received only natural backgro- und radiation and the other was exposed to supplemental UV-B radiation）, and we studied the effects of NO scavenger on increased of the gas exchange parameters and contents of chlorophyll in cloned integration under heterogeneous UV-B conditions. The result showed that in comparison with clones under homogeneous ultraviolet-B radiation, the gas exchange parameters and contents of chlorophyll increased notably if heterogeneous ultraviolet-B stressed connected treatment of Glechoma longituba, and the results were reversed by NO scavenger. This indicated that NO, as a signal molecule, had important effect on physiological integration of cloned plant which increased the photosynthetic physiological characteristic of Glechoma longituba. The results could be helpful for further understanding of the effect of UV-B radiation on growth regulation of cloned plants and provided the theoretical foundation about mechanism of heterogeneous UV-B radiation on physiological integration in clonal plants.