不同冬小麦品系对UV-B的生理响应

Research on the Different UV-B Resistance of Two Winter Wheat

为了解不同小麦基因型对UV-B增强响应的生理差异,以植株生长对UV-B呈正响应的冬小麦品系农大6081和呈负响应的冬小麦品系9305031-2为材料,在人工气候室内于出苗后每天用强度为15μW·cm-2的UV-B照射6h,比较了两个品系生长、光合、UV吸收物质、膜透性、H2O2积累量与清除能力等指标的差异。结果表明,UV-B辐射处理后,农大6081株高、干重、PSII活性、SOD和CAT活性,以及叶片可溶性蛋白、类胡萝卜素和类黄酮等UV吸收物质的含量增加,叶片H2O2含量降低,膜系统的电解质渗漏有所缓解,活性氧的生成得到有效控制;而9305031-2的SOD、CAT活性没有提高,类胡萝卜素含量、叶绿素含量、株高、叶面积、干重、PSII活性下降。说明农大6081与9305031-2生长对UV-B辐射的响应差异可能与活性氧生成和清除能力不同有关。

In this study,the winter wheat Nongda 6081 whose growth was promoted by a certain intensity of UV-B in seedling stage and the winter wheat 9305031-2 whose growth was inhibited were used as materials.These two cultivars were irradiated by UV-B（15 μW·cm-2,6 h per day） after the emergence in the phytotron and then related indexes of growth,photosynthesis,UV-absorbing materials,membrane permeability,H2O2 accumulation and removal ability were all compared and analyzed.The results showed that,UV-B treatment promoted the plant height,dry weight,PSII function,SOD activity,CAT activity,content of soluble protein,and content of UV-absorbing materials such as carotenoids and flavonoids of resistant winter wheat Nongda 6081,but decreased the content of H2O2 and the electrolyte leakage of membrane systems,suggesting that the producing or removal of ROS and H2O2 was effectively controlled.But,the activities of SOD and CAT of sensitive winter wheat 9305031-2 were not improved and the content of carotenoids was inhibited,resulting that a great quantity of H2O2 was accumulated and content of chlorophyll,plant height,leaf area,dry weight,PSII function and membrane system were inhibited.It was concluded that,the resistance difference between Nongda 6081 and 9305031-2 was mainly caused by the difference in the metabolism of ROS.