水稻穗形态建成基因PMM1的遗传分析与初步定位

在水稻粳稻品种中花11T-DNA插入突变体库中鉴定了3个穗形态突变体,它们均表现为植株半矮、叶夹角变小、一次枝梗轮生、复粒、粒长变短、粒宽变宽等突变表型。基因双突变杂交F1表型考查证明这3个突变体为等位突变体,T-DNA标签共分离检测表明这3个突变体的表型与T-DNA插入无关。通过与籼稻品种珍汕97配置3个杂交组合,由经典的孟德尔遗传分离比显示,突变性状受1对隐性基因(panicle morphological mutant 1,PMM1)控制。采用基因图位克隆的方法,已将基因PMM1定位在第4染色体长臂上的RM3866-1和X4(InDel)标记之间,其两侧物理图距为147kb左右。

Genetic analyses and preliminary mapping of a panicle morphogenesis mutant (PMM1) in rice

Three panicle morphogenesis mutants were identified from a T-DNA insertional mutant library of the japonica rice variety Zhonghua 11.All these mutants exhibited as semi-dwarf,reduced leaf angle,whorled primary branches,shortened and widened grains.The same mutant phenotype of F1 generated by parallel crossing between three mutants verified that they were allelic.Cosegregation analysis of T-DNA tag confirmed that the mutant phenotypes were not caused by T-DNA insertion in the genome.Three F2 mapping populations were generated by individually crossing mutants with Zhenshan 97.The segregation ratio of mutants and wild-types indicated that the mutant traits were controlled by a single recessive gene(panicle morphological mutant 1,PMM1).Through map-based cloning,PMM1 was located between molecular markers RM3866-1 and X4(InDel) on the long arm of chromosome 4,with physical region about 147 kb.This research will provide a foundation for further mapping and characterization of the PMM1 gene in rice.