Abstract: It is of great importance for field yield of fruit trees to generate flower buds. Recently, FT protein has been proved to be a florigen in higher plants. In this study, full-length cDNA of MdFT gene, a homolog of Arabidopsis AtFT, was amplified from apple leaf cDNAs with RT-PCR. Subsequently, a plant expression construct containing MdFT gene driven by cauliflowermosaic virus 35S promoter was obtained and introduced into tomato cultivar ‘Zhongshu 4 ’with Agrobacterium-mediated transformation. In parallel, Arabidopsis AtFT gene was transformed as a positive control. Finally, transgenic tomato lineswere regenerated from selection medium plus kanamycin. PCR amp lification verified the integration of exogenous genes into the host genome, and semiquantitative RT-PCR disp layed their ectopic overexpression in transgenic tomatoes. Furthermore, morphological observation found that transgenic tomato lines flowered earlier than the non-transgenic control, suggestive of our successful cloning of florigen gene MdFT from apple, which has the
potential as a target gene to shorten juvenility in apple tree.

Key words: apple, FT gene, ectopic overexpression, tomato