new fertility restorer locus linked closely to the Rfo locus for cytoplasmic male sterility in radish

• Published in: Theoretical and applied genetics 2008-08, Vol.117 (3), p.313-320
• Main Authors: Wang, Zhi Wei, Zhang, Yu Jie, Xiang, Chang Ping, Mei, Shi Yong, Zhou, Yuan, Chen, Guo Pei, Wang, Ting
• Format: Article
• Language: English
• Subjects: Agriculture; Alleles; Amplified Fragment Length Polymorphism Analysis; Base Sequence; Biochemistry; Biological and medical sciences; Biomedical and Life Sciences; Biotechnology; Classical genetics, quantitative genetics, hybrids; Cloning; Cloning, Molecular; Cytoplasm - genetics; Cytoplasm - physiology; DNA, Plant - genetics; DNA, Plant - metabolism; Fertility; Fertility - genetics; Fundamental and applied biological sciences. Psychology; Gene Expression Profiling; Gene Expression Regulation, Plant; Genes; Genes, Plant; Genetic Markers - genetics; Genetics of eukaryotes. Biological and molecular evolution; Life Sciences; Mitochondrial DNA; Molecular Sequence Data; Original Paper; Plant Biochemistry; Plant Breeding/Biotechnology; Plant Genetics and Genomics; Plant Infertility - genetics; Plant reproduction; Pollen - genetics; Polymerase Chain Reaction; Proteins; Pteridophyta, spermatophyta; Radio frequency; Raphanus - genetics; Sequence Alignment; Transcription, Genetic; Vegetals
• ISSN: 0040-5752; 1432-2242
• DOI: 10.1007/s00122-008-0776-5

In this study, we have investigated a new fertility restorer (Rf) locus for cytoplasmic male sterility (CMS) in radish. We have obtained a CMS-Rf system consisting of sterile line '9802A1', maintainer line '9802B1' and restorer line '9802H'. F₁ plants from cross between sterile line '9802A1' and restorer line '9802H' were all male fertile, self pollination of F₁ plants produced an F₂ segregating population consisting of 600 individuals. The segregating population was found to fit a segregation ratio 3:1 for male fertile and sterile types, indicating that male fertility is restored by a single dominant gene (termed Rfo2) in the CMS-Rf system. Based on the DNA sequence of Rfo/Rfk1 (AJ535623), just one full length gene in the sterile line '9802A1', in the restorer line '9802H' and in the male fertile line '2006H', was cloned, respectively. The three sequences correspond to the same gene with two alleles: Rfob in '9802H' and rfob in '9802A1' and '2006H'. These two alleles differ from Rfo/Rfk1 and rfk1 (AJ535624) alleles by two synonymous base substitutions, respectively. Based on the differences between the Rfob and rfob genes, one PCR-based marker was developed, and designated Marker 1, which is identical to the corresponding region of Rfob by sequence analysis. In the F₂ segregating population described above, the Marker 1 was present in 5 sterile plants and in 453 fertile plants, absent in 4 fertile plants and in 138 sterile plants, and was found to fit a segregation ratio 3:1 indicating that Rfob was single copy in '9802H'. Linkage analysis showed that the Rfo2 locus for our CMS-Rf system was distant from the Rfo locus by about 1.6 cM. The sterile line '9802A1' was pollinated by the male fertile line '2006H' and the resulting F₁ plants were all male fertile. These results indicated that the male fertility of radish CMS can be restored by a new Rf locus, which linked tightly to the Rfo locus.