辐射诱变是农作物种质创新的重要手段。本研究以杂交稻骨干亲本T98B为研究对象，以300 Gy剂量的60Coγ射线对其成熟种子进行处理，从辐射后代中鉴定出农艺性状变异材料，划分了变异类群，分析了各类型突变频率，为遗传改良奠定了材料基础。结果显示， 经γ射线处理后的M1和M2种子的发芽率受到了显著抑制，分别比对照T98B降低了22.35%和14.67%；从M2群体中初步筛选出了207个变异单株；经M3〖KG-*3〗～M5的遗传稳定性测试后最终获得了168份可稳定遗传的突变体，总突变频率达到了0.673%。按照变异部位将突变体划分成叶变异、茎/蘖变异和穗粒/花变异等3种类群，各类群分别含有34份、37份和97份突变体，占比20.24%、20.02%和57.74%；育性、叶色和株高等性状的突变频率较高，分别达到了0.212%,0.092%和0.088%。此外，本文简要描述了各类群的表型变异特点。结果表明，利用γ射线诱变能产生丰富的农艺性状突变体，本研究为水稻遗传改良提供新的种质资源奠定了基础。

Radiation mutagenesis is available for crops germplasm creation. In this study, gammaray irradiation was used to induce the rice cultivar T98B which is a main maintainer line of hybrid rice, under the treatment of mature seeds at a dose of 300 Gy. It focused on  screening and grouping of agronomic mutants, and the frequency for each type was also investigated. The results showed that, by contrast of T98B, the germination rate for M1 plants and M2 plants were both significantly suppressed, with a decrease of 22.35% and 14.67% respectively. In M2 population, 207 candidate mutants were screened. Of which, 168 were validated steadily inheritable via a phenotyping test from M3 to M5, accounting for a total mutation frequency of 0.673%. Furthermore, they were divided into 3 groups regarding leaf group, stem/tiller group and grain/flower group, according to the part that it occurred to mutate on. Each group above included 34, 37 and 97 mutants respectively, representing a ratio of 20.24%, 20.02% and 57.74%. The common mutants were the ones varied on fertility, leaf color and plant height, and it presented a mutation frequency of 0.212%,0.092% and 0.088% respectively. Moreover, a brief description on the phenotypes for each group was provided. The results indicated that, agronomic mutants in rice could be effectively obtained via gammaray irradiation, and several mutants gained here would be severed as useful germ resources for advancing the work on rice genetic improvement.