分别采用5 mW·mm-2He-Ne激光辐照、10.08 kJ·m-2·d-1增强紫外线-B(UV-B)辐射及二者组合对“晋麦8号”小麦幼苗进行处理,5 d后测定各处理幼苗叶片和根的RNA酶(RNase)和DNA酶(DNase)活性变化。结果表明,经UV-B辐射后,小麦幼苗叶片和根的核酸酶活性均有明显升高,电泳图谱中其酶谱带均没有增加,只是酶活性的升高;复合处理的小麦幼苗其酶活性较之单独UV-B辐射的有显著或极显著降低,电泳后的酶谱带也没有减少,只是活性下降。因此认为一定剂量的He-Ne激光辐照能抑制UV-B辐射后小麦幼苗核酸酶活性的升高。

Wheat seedlings were exposed to He-Ne laser irradiation (5 mW·mm-2 power density),enhanced ultraviolet-B (UV-B) radiation (10.08 kJ·m-2·d-1),and the combination of He-Ne laser irradiation and enhanced UV-B radiation for 5 days. Changes of DNase activity and RNase activity in the leaves and roots of wheat seadlings were measured to test the potential reparative role of He-Ne laser irradiation. The results show that exposing the seedlings to UV-B radiation results in the increase of the nuclease activity of the leaves and roots. The electrophoresis pattern of nuclease shows that enzyme spectrum zones do not increase,whereas enzyme activity increases. After irradiating by UV-B and the He-Ne laser,the nuclease activity of the leaves and roots becomes is lower than their activity under UV-B radiation alone. The electrophoresis pattern of nuclease also shows that enzyme spectrum zones do not decrease,whereas enzyme activity decreases. The results suggest that damage,induced by enhanced UV-B radiation on wheat seedlings,which affects the activity of nuclease in leaves and roots,can be repaired partially by He-Ne laser irradiation.