Effectiveness of usage inducible site-specific recombinase and a bifunctional selectable gene for production of marker-free fruit crops

The generation of transgenic plants without any foreign genetic material, especially bacterial and viral origin relieves public concerns and facilitates future commercialization of GM crops. Some strategies have been developed to eliminate the marker gene from the plant nuclear genome after selection. In our study, we used the pMF vector system (PRI, Wageningen) containing the R recombinase and a CodA-nptII bifunctional selectable gene for produce tomato and apple plants carrying the supersweet thaumatin II gene from tropical plant Thaumatococcus daniellii under the control of tomato fruit-specific ELIP or E8 gene promoter and tomato Rubisco terminator. By using different strategies of early and delay selection we developed a protocol and fully marker-free tomato and apple plants were obtained.