Hybrid sterility is the main barrier in util-izing the heterosis of subspecies in rice. A knowledge of the underlying molecular mechanism of the hybrid sterility will be useful for overcoming the barrier. In this rese...Hybrid sterility is the main barrier in util-izing the heterosis of subspecies in rice. A knowledge of the underlying molecular mechanism of the hybrid sterility will be useful for overcoming the barrier. In this research, the F1 pollen sterility locus, S-b, was mapped between SSR markers PSM8 and PSM202. To fine map the locus, one F2 mapping population of 3910 plants was developed using the near-isogenic lines of the locus. Ninety-seven recombinants be-tween two markers were selected. Moreover, a series of markers, including two SSR markers, two InDel markers and four CAPS markers, were developed on the region. Linkage analysis showed that marker W4 was co-segregated with locus S-b, while makers A8 and A14 were located on the two sides of the locus with a distance of 0.026 and 0.038 cM, respectively. The markers were then integrated with the se-quences of the clones of the region. Results showed that all the polymorphic markers were anchored on the three end-to-end jointed clones AC093089, AC079021 and AC134931. According to the physical information of the markers, locus S-b was finally de-limited to a region of 27 kb between A8 and A14. Seven ORFs were identified on the region based on the annotation results of RiceGAAS system. These results laid the foundation for further cloning the gene.展开更多
In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its nea...In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its near-isogenic line TIST2 carrying S-b(i)/S-b(i) 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 Taq I. Genetic analysis indicated that the distance between locus S-b and markers, R830STS, RM13 and R2213SSTS were 3.3 cM (centi-Morgan), 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.展开更多
文摘Hybrid sterility is the main barrier in util-izing the heterosis of subspecies in rice. A knowledge of the underlying molecular mechanism of the hybrid sterility will be useful for overcoming the barrier. In this research, the F1 pollen sterility locus, S-b, was mapped between SSR markers PSM8 and PSM202. To fine map the locus, one F2 mapping population of 3910 plants was developed using the near-isogenic lines of the locus. Ninety-seven recombinants be-tween two markers were selected. Moreover, a series of markers, including two SSR markers, two InDel markers and four CAPS markers, were developed on the region. Linkage analysis showed that marker W4 was co-segregated with locus S-b, while makers A8 and A14 were located on the two sides of the locus with a distance of 0.026 and 0.038 cM, respectively. The markers were then integrated with the se-quences of the clones of the region. Results showed that all the polymorphic markers were anchored on the three end-to-end jointed clones AC093089, AC079021 and AC134931. According to the physical information of the markers, locus S-b was finally de-limited to a region of 27 kb between A8 and A14. Seven ORFs were identified on the region based on the annotation results of RiceGAAS system. These results laid the foundation for further cloning the gene.
文摘In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its near-isogenic line TIST2 carrying S-b(i)/S-b(i) 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 Taq I. Genetic analysis indicated that the distance between locus S-b and markers, R830STS, RM13 and R2213SSTS were 3.3 cM (centi-Morgan), 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.
