Characterization And Molecular Mapping Of Reverse Thermo-sensitive Genic Male Sterile Lines Derived From The Progeny Of Distant Cross Between Cultivated Rice(Oryza Sativa L.)and Wild Rice(Oryza Rufipogon Griff.)

Within the scope of the whole world, over half of population was feed on rice as a staple food, so its yield and quality impose a direct influence on food security. Three-line breeding system developed in1970s had brought the second revolution in the history of rice breeding, gave rise to a great enhancement of rice yield. With the progress of technology, three-line has gradually exhibited some disadvantages, including low quality in rice, limitation on further enhancement of yield, negative effects of sterile cytoplasm and potential dangerous from single cytoplasm and so on, during its course of application and commercial extension. Two-line breeding has a wide application in practice as which can overcome the shortcomings in three-line system, while we haven’t gotten a clear and thorough understanding of photoperiod or thermo-sensitive genic male sterility, hindering the consummation and further application of two-line system. Hence, our research on fertility identification, genetic analysis and molecular mapping of reverse thermo-sensitive genie male sterile lines81S and N13S has both theoretical and practical significance.The results showed that81S is a reverse TGMS line with the critical temperature for fertility transformation of25-26℃. The panicle, anthers and pollen fertility exhibited distinct differences with comparison to normal cultivar. In the cross combination of81S/Zhong1159, the segregation ratio fitted well with3:1, revealing a single recessive gene, designated as rtms2, conferring the sterility. In addition, previous study within our group showed that the sterility of N13S was also controlled by a single recessive gene, named as rtms3.In the cross combination of81S/Zhong1159, a total of13SSR/STS markers,11InDels and5CAPs/dCAPs markers from newly developed61InDels and13CAPs/dCAPs showed polymorphism between the two parents. PCR analysis of sterile plants with polymorphic molecular markers located rtms2within an interval of130kb between InDe153and InDe112and co-segregated with InDe160. According to public information of rice genome annotation project, there were12genes within the130kb interval. Four genes, protein phosphatase2C, glucan1,3-p-glucosidase precursor, pollen specific protein C13precursor and AP2domain transcriptional regulator seems interesting to us for their particulars. These results from RGAP will be useful for our further study.In another combination between N13S and Zhong1159, rtms3was mapped between E61552and S15528with8polymorphic markers, with genetic distance of2.22cM and4.45cM, respectively.