In cultivated rice (Oryza sativa L.), F1 pollen sterility is controlled by at least 6 loci of the F1 pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-bj/S-bj and its near-isogenic line TISL2 carrying S-bi/S-bi were used to develop the mapping population. One hundred and fifty-eight microsatellite markers were selected to survey T65 and TISL2. RM13 on chromosome 5 was found to be polymorphic between them. Cosegregation indicated that RM13 was closely linked with locus S-b. Eleven RFLP markers were selected on the corresponding region from the genetic map of Rice Genome Research Program (RGP) of Japan to convert into sequence-tagged site (STS) markers. Amplicon length polymorphism (ALP) was carried out, but none of them was found to be polymorphic between T65 and TISL2. Then PCR-based RFLP (PBR) was done using six 4-nucleotide recognizing restriction endonucleases. Polymorphism was detected when PCR products of R830STS and R2213SSTS were digested with TaqⅠ. Genetic analysis indicated that the distance between locus S-b and markers R830STS, RM13 and R2213SSTS were 3.3 cM (centiMorgan), 5.2 cM and 5.5 cM, respectively. These PCR-based markers could be directly used in marker-assisted selection. The technical system combining genetic mapping and PCR-based marker-assisted selection will facilitate the development of molecular breeding.%栽培稻(Oryza sativa L.)杂种F1花粉不育性至少由6个基因座位所控制.为了定位其中的一个基因座位S-b,选用了158个微卫星标记对粳型品种"台中65"及其近等基因系TISL2之间的多态性进行了分析.结果发现第5染色体短臂上的RM13在亲本间存在多态性.连锁分析表明,RM13与S-b座位紧密连锁.根据微卫星标记分析的结果,在RGP(Rice Genome Research Program of Japan)发表的遗传图谱的相应位置上选取了11个RFLP标记,利用这些标记的末端序列设计特异PCR引物,进行ALP (amplicon length polymorphism)分析,结果11对引物均没有ALP.用6种四碱基识别位点的限制性内切酶进行PBR(PCR-based RFLP)分析,发现由R2213S和R830两克隆设计的STS (sequence-tagged site)标记在T65与TISL2之间存在酶切多态性.R830STS、RM13和R2213SSTS与S-b座位的遗传距离分别为3.3 cM (centiMorgan)、5.2 cM和5.5 cM.这些以PCR为基础的分子标记可以直接应用于分子标记辅助选择中,从而建立了基因定位与分子标记辅助选择一体化的技术体系,使S-b座位在育种中可以得到有效的利用.
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