He-Ne激光和增强UV-B辐射对小麦幼苗多酚代谢3种酶活性的影响

Effect of He-Ne laser and enhanced ultraviolet-B radiation on the activities of three polyphenol metabolism enzymes in wheat seedling

为探讨He-Ne激光和增强UV-B辐射对小麦幼苗多酚代谢相关酶活性的影响,利用5mW·mm-2的He-Ne激光和增强UV-B(10.08kJ·m-2·d-1)辐射处理"晋麦8号"小麦幼苗,分别在不同时段测定苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)及过氧化物酶(POD)的活性。结果表明,增强UV-B辐射使小麦幼苗叶片PAL活性升高,PPO与POD活性降低,且随处理天数的增加,不同处理组小麦幼苗叶片PAL、PPO、POD活性间具有一定相关性。长期增强UV-B辐射,导致多酚类物质的代谢速度降低甚至停止,自由基不能被及时清除,生物膜破坏;经过一定剂量的He-Ne激光辐照可修复增强UV-B辐射对小麦幼苗叶片多酚类物质代谢的损伤。

＂Jinmai No. 8＂ wheat seedlings were exposed to He-Ne laser irradiation （5 mW·mm-2） and enhanced UV-B radiation （10.08 kJ·m-2·d-1） and the effect on the activities of three polyphenol metabolism enzymes （phenylalanine ammonialyase, polyphenol oxidase and peroxidase） in wheat seedling analyzed. The results show that UV-B radiation enhances wheat seedling phenylalanine ammonialyase activity while it limits activities of polyphenol oxidase and peroxidase. The activities among phenylalanine ammonialyase, polyphenol oxidase and peroxidase in different treatment groups get related with treatment time increased. The long-term enhanced UV-B radiation reduces polyphenol metabolic rate, breaking up biomembranes as free radicals accumulate with time. Damage to wheat seedlings induced by the enhanced UV-B radiation on polyphenol metabolism is limited by He-Ne laser irradiation.