一个新水稻低温敏感叶色突变体tcm11的鉴定及基因定位

Identification and gene mapping of a novel low temperature sensitive leaf color mutant tcm11 in rice (Oryza sativa L.)

对粳稻"嘉花1号"经^(60)Coγ诱变处理获得的稳定遗传低温敏感叶色突变体tcm11(thermo-sensitive chloroplast mutant 11)进行了表型鉴定与遗传分析.在20℃条件下,该突变体三叶期之前幼苗均表现为黄色,光合色素含量明显下降,叶绿体发育不完整,从第4叶开始逐渐转为浅黄绿色直至最后死亡.而在32℃条件下,其表型与野生型相比没有明显差异,具有低温敏感属性.通过对培矮64S与tcm11杂交的F_2代分离群体进行遗传分析,发现该低温敏感突变体性状是受单个隐性核基因(tcm11)控制,利用图位克隆技术对tcm11进行定位,将其定位在第11号染色体的InDel分子标记ID13252与SSR分子标记MM1361之间一个约1 566 kb的区域内.这也为后续的研究奠定了基础.

A stable geneticlow temperature sensitive leaf color mutant tcm l l （thermo-sensitive chloroplast mutantll） derived from Japonicarice variety Jiahua No. 1 treated by 60 Co ^y-rays was used in this study, whichwasidentified the phenotypic character-ization and genetic analysis. Underthe condition of 20 , the tcml 1 mutant was showed the etiolation phenotype before 3-leaf-stage,which were greatly reduced the photosynthetic pigment contents andbroken the chloroplast structure. However, it began to turn the yellow green phenotype after 4-leaf-stageuntil it died. But under the condition of 32 ,its phenotype was no significant difference compared with wild type （ Jiahua No. 1 ） , with low temperature sensitive attributes. Using segregatingindividuals from cross of Peii 64S and t cmll , genetic analysis revealed that the mutant phenotype was controlled by a single recessive nuclear gene. Through map-based cloning, the mutant gene （ tcml1 ） was located to 1 566 kb region between the molecular markers ID13252 and MM1361 on rice chromosome 11, which also the follow-up research laid the foundation for in the future.