【摘要】 广亲和(WC)是水稻(OryzasativaL.)亚种间杂种优势利用的重要遗传工具。本研究对我国南方大面积推广应用的亚种间两系杂交稻亲本培矮64S的WC基因S-5n进行分子标记定位。从培矮64S//T8/秋光三交F1中选出由263个高育和低育极端类型组成的标记群体,选用来源于CornellSSR连锁图的20个标记和根据GenBank数据库公布的序列合成的9个SSR标记,通过BSA(分离群体分析)法对标记群体进行分析,该S-5位点精确定位于第6染色体上,距SSR标记GXR6和RM276的距离只有0.2cM。培矮64S的S-5n对育性贡献可使小穗结实率从平均43.5%提高到77.5%,贡献率达34.0%,表明它是一个很强的控制广亲和特性的主效基因。本研究所获得的这些紧密连锁标记对分子标记辅助选择培育广亲和水稻品种和基因克隆具有重要的利用价值。更多还原

【Abstract】 Wide compatibility (WC) is an important genetic tool for exploitation of inter-specific heterosis in rice (Oryza sativa L.). In this study, Pei’ai 64S, one of the most popular thermosensitive genic male sterile (TGMS) line widely used for subspecific hybrid rice breeding program in South China, was studied to locate its WC allele S-5n by exploiting SSR markers. A mapping population containing 263 extreme fertile and sterile plants was developed from a three-way cross (Pei’ai 64S/T8//Akihikari). Surrounding the S-5 locus, 29 SSR (simple sequence repeat) markers of which 20 derived from Cornell SSR linkage map and 9 developed using sequences from GenBank database, were employed for the molecular assay. The bulked segregant analysis was performed to tag fine location of the locus. This S-5 locus was mapped on chromosome 6 approximately 0.2cM from both of the SSR markers GXR6 and RM276. The contribution of the S-5n allele to spikelet fertility reached as high as 34.0% in Pei’ai 64S , increasing from 43.5% to 77.5%, indicating it was a main effect gene controlling the wide compatibility. The tight linkage markers would be very useful for efficient marker-assisted selection of rice WC varieties and map-based cloning of the gene.更多还原