粳稻伞穗型突变体的诱发与特性评价

采用60Coγ射线200Gy辐照处理晚粳稻密穗型材料U5纯系干种子,经加代筛选后,获得了粳稻伞状穗型突变体,取名为ET2。与原亲本比较,ET2穗部形态发生了明显变异,其一次枝梗着生角度显著增大,与穗轴的张开角达30°~40°;其未成熟粒、垩白粒率和垩白度分别减少41.8%、39.8%和59.1%;其籽粒产量提高4.15%。分析ET2穗部不同部位籽粒特性表明,在未成熟粒和垩白改良方面,其穗下部显著优于穗中部,而穗中部又优于穗上部。ET2的诱发可能是培育籽粒优良、密穗型高产晚粳稻品种的一条有效途径。

INDUCTION AND EVALUATION OF UMBRELLA TYPE PANICLE MUTANT IN Japonica RICE

The dried seeds of pure Japonica rice,line c.v.U5,with compact type panicle were irradiated by 200Gy()~(60)Co γ-rays.Based on the observation and selection in the following generations,a mutant with umbrella type panicle was developed,and named as ET2.Compared with its parent U5,ET2 showed obvious difference in panicle type,the angle of its primary rachis-branchs was enlargeed to about 30°～40°;unripen grains,chalky grain rate and chalkiness degree decreased by 41.8%,39.8% and 59.1%,respectively,and yield increased by 4.15%.The analysis on traits of grains in different part of panicle showed that in the bottom grains improvement of unripen grains and chalkiness were much better than in the iddle ones,and much better than in the top ones within the panicle.Induction of ET2 might be an effective way for improving quality of grain in japonica rice varieties with compact panicle.