一个新的水稻半矮化小穗突变体的遗传分析与基因定位

Genetic Analysis and Gene Mapping of a New Semi-Dwarf and Small Panicle Mutant in Rice

从粳稻中花11转基因后代中发现了一个半矮化小穗突变体,表现为植株半矮化、生长势弱、半包茎穗、穗型变小等特点,将其命名为sdsp2(semidwarfandsmallpanicle2)。遗传分析显示,该突变体表型受1对隐性核基因控制。以sdsp2突变体为母本与龙特甫B杂交构建F2分离群体,将该基因定位在水稻第6染色体的RH6-32和RH6-40之间的116kb的物理距离内。通过水稻基因组注释系统在此区域预测到14个开放阅读框,未发现与已报道穗型发育相关基因的同源基因。

A semi-dwarf and small panicle mutant was obtained from a japonica rice variety Zhonghua 11 through T-DNA transformation.The mutant,characterized by semi-dwarf plant,abnormal small and semi-enclosed panicle,and poor growth potential was designated as sd-sp2（semi-dwarf and small panicle 2）.Genetic analysis indicated that the mutant was controlled by a single recessive gene.A genetic linkage map was constructed using an F2 mapping population derived from a cross between the sd-sp2 mutant and an indica variety Longtefu B on chromosome 6.The gene was finally located on a 116-kb region between the STS markers RH6-32 and RH6-40,where 14 ORFs were predicted based on Rice Genome Annotation.