本文研究EDTA对γ射线诱发水稻突变的修饰效应。结果表明,γ射线和EDTA复合处理对水稻M_1代的损伤效应大于单-γ射线处理。诱发M_2代叶绿素缺失突变、抽穗期和株高突变的频率也高于单一处理。结果还表明,应用椭圆法筛选抽穗期和株高这两个数量性状同时突变的频率,优于突变界限法。前者能更真实地反映诱变效率和突变方向。 This article studies the effect of EDTA on γ-ray-induced rice mutant modification. The results showed that γ-ray and EDTA combined treatment had greater damage effect on M_1 generation than single γ-ray treatment. The chlorophyll deletion mutation was induced in M_2 generation, and the frequency of heading stage and plant height mutation was also higher than that of single treatment. The results also show that the application of ellipse screening heading and height of these two quantitative traits simultaneously mutation frequency, better than the mutation limit method. The former can more truly reflect the mutagenesis efficiency and mutation direction.