The objective of this project is to evaluate the efficacy of the FLP/F2T site-specific recombinase in excising a transgenic tapetum-specific promoter driving an inverted (antisense) Arabidopsis fertility gene, bet l . Plants containing the antisense of bell (flanked by FRT sites) will be male sterile and when crossed to plants containing the FLP site-specific recombinase, FLP should excise the sterility gene thus restoring fertility and producing a hybrid. In addition, the relative effectiveness of different structural alterations in the FRT sites will be assessed with respect to the efficiency of transgene excisions. If this FLP/FRT system functions at sufficient efficiencies, it will confirm the feasibility that it can be used as a new method for making hybrid plants. During Phase II of this SBIR, it will be our intention to use the same system, if it proves to be feasible during Phase I research, for the development of corn hybrids.Applications:It is anticipated that this research will establish that the site-specific recombinase system (FLP/FRT) will be sufficiently Ancient when two plants are crossed (and the two components of the FLP/FRT system reside in different plants), to excise a male-sterility system, and thus to provide a new method for producing plant hybrids. The first application would be for the production of hybrid maize and will provide an alternative to detasselling or the use of ems maize. It is possible that the same system could be extended to other crops of economic importance such as wheat, soybeans, etc.
