Studies On Establishion Of Tomato High-Frequency Regeneration System And Transformation Of Frutan Fructosyl Transferase

The asexual systems of Tomato(Ly-copercicon escu]en turn Mill) Cultivars GuiFei and Bijiao were established in the study. Effects of different factors on the regeneration of tomato cotyledons, hypocotyls, stems and leaves were compared, and the factors of affecting transformation frequency were also studied. Agrobacterium LBA4404 (pTSB) was used for transformation and then transgenic plantlets with fructan fructosyl transferase gene(FFT) of Bijiao were obtained, and rooted very well in the rooting medium with KmSOmg/L. By Southern analysis, the result proved that the FFT gene has been integrated into the genome of BiJiao. By antifreezing experiments, the detect on electrical conductivities of the leaves, and the detect on the content of polysaccharides, the results proved that fructan fructosyl transferasq gene in transgenic plantlets has been expressed. The main progress of this study was as followings: 1. The asexual systems of tomato cultivars GuiFei and BiJiao were established by directly inducting buds of the explantations of cotyledons, hypocotyls, stems and leaves, and the average regeneration frequency of them could reach to more than 95 percent. 2. The appearance of turning brown of leaves and stems could be modified by adding Vc to the regeneration medium, but if the Vc was being added or was overdded, the regenerative ability of the explantations would be declined, and the optimum concentration was 50OOmg/L. 3. The ability of regeneration and differentiation was increased by adding AgNO3 solution to the regeneration medium, and the length growth of buds was also increased. The optimum concentration of AgNO3 solution in the regeneration mediums of leaves and stems was lmg/L and 3mg/L respectively. 4. Transformation frequency of LBA4404(pTSB) in two cultivars Bijiao and GuiFei was compared in this study, The one of BiJiao was higher than GuiFei, and the induction frequency of resistant calluses was 15. 50 percent. The transgenic explantations of Bijiao regenerated into plantlets, and the transgenic plantlets rooted well in the rooting medium containing Km5Omg/L. 5. The fructan fructosyl transferase gene(FFT) has been integrated into the genome of Bi.Jiao, which was proved by Southern analysis. 6.The antifreezing experiments on the transgenic plantlets of Bijiao proved that there was obvious difference of growth between the transgenic and nontransgenic plantlets at C . The antifreezing ability of the transgenic plantlets was much higher than that of flontransgenic plantlets. 7.The detect on electrical conductivities of the leaves of the plantlets was done. The electrical conductivities of the transgenic plantlets were less than that of nontrnsgenic plantlets in the low temperature, and the transgenic plantlets appeared stronger antifreezing ability. 8. In the phenotype, the transgenic plantlets appeared in the low temperature that transgenic plantlets could grow and breed very normally, which proved whose antifreezing ability was stronger than that of nontransgenic plantlets. 9. 13y the detect on the content of polysaccharides of leaves, stems and fruits of tomato, the polysaccharides content of the transgenic plantlets was higher than that of nontransgenic p...