Genetic Analysis And Mapping Of Fertility-restorer Genes For HL,CL Type Cytoplasmic Male Sterility In Japonica Rice

Now, varieties of japonica hybrid rice are mainly developed basing on Chinsurah Boro(BT)-type CMS. Because of unstability of sterility of BT-CMS, researches on developing new type CMS for japonica hybrid rice with are very important. Two sterile cytoplasm sources from Hainan Red Awned Wild Rice(HL type) and Hunan Chaling Wild Rice(CL type) have been confirmed to be used for japonica hybrid rice in the former studies, So genetic analysis and mapping of fertility-restorer genes in japonica rice with HL、CL type CMS are important to promote the breeding of HL, CL-CMS lines and their corresponding restorer lines for solving the problems of single type sterile cytoplasm used in current japonica hybrid rice and unstable sterility of BT-CMS lines.In this paper, work was taken to genetic analysis and mapping of fertility-restorer genes for HL, CL type CMS in japonica rice by using HL-LiuqianxinA, CL-LiuqianxinA and HL-SuqiuA and their corresponding maintainer lines, two restorer lines(SiR2982, SWR78). And the results show:1. According to the fertility segeration of three populations (HL-LiuqianxinA//LiuqianxinB/SiR2982, CL-LiuqianxinA//LiuqianxinB/SiR2982, HL-SuqiuA//SuqiuB/SWR78), it could be speculated that the fertility restoration of HL, CL type CMS in japonica rice was controlled by a pair of dominant major gene with χ2test.2. By the fertility of plants in F2populations derived from three combinations (HL-LiuqianxinA/SiR2982, CL-LiuqianxinA/SiR2982, HL-SuqiuA/SWR78), it could be concluded that HL, CL type CMS in japonica rice were gametophytic male sterility.3. The sterile plants derived from the three-cross populations of HL-LiuqianxinA//LiuqianxinB/SiR2982and CL-LiuqianxinA//LiuqianxinB/SiR2982were used to map the fertility-restoring gene. The Rf genes were mapped on the longarm of chromosome10, localized between STSh-52and STS10-19, indicating that the Rf genes in SiR2982for HL, CL type CMS in japonica rice were the same.4. The sterile plants derived from the three-cross population of HL-LiuqianxinA//LiuqianxinB/SiR2982were used to map the fertility-restoring gene. The Rf gene was mapped on the longarm of chromosome10, localized between STSh-52and STS10-19, and the physical distance of the interval between the two markers was about208kb. Then, the fertile plants of the populations were chose to map the fertility-restoring gene. Two genes(Rf-hl-al (t)、Rf-hl-a2(t)) were located at the same location. Rf-hl-al(t) was localized between STSh-52and STS10-69, and the physical distance of the interval between the two markers was about142kb, and Rf-hl-a2(t) was localized between STSh-13and STS10-19, the distance was about55Kb.5. The sterile populations plants derived from the three-cross population of HL-SuqiuA//SuqiuB/SWR78were used to map the fertility-restoring gene. The Rf gene was mapped on the longarm of chromosome10, localized between STSh-46and STS10-75, and the physical distance of the interval between the two markers was about210kb. Then, Then, the fertile plants of the population were chose to map the fertility-restoring gene too.Two genes(Rf-hl-bl (t)、Rf-hl-b2(t))were located at the same location. Rf-hl-b1(t) was localized between STSh-46and STS10-75, and the physical distance of the interval between the two markers was about72kb, Rf-hl-b2(t) was localized between STSh-65and STS10-79, the distance was about96Kb. 6. Compared with the mapping results of Rf genes for other type CMS gained in former studies, we speculated that Rf-hl-al(t) and Rf-hl-b2(t) might be the same gene as Rf1a cloned in BT type CMS in japonica rice.