Agrobacterium-mediated transformation of Saintpaulia ionantha Wendl.

Agrobacterium tumefaciens strain LBA4404 that has pTOK233 and other two strains that have pIG121Hm were co-cultivated with suspension cells of Saintpaulia ionantha Wendl. 'Pink Veil'. These two plasmids contain an intron-gusA reporter gene, hygromycin phosphotransferase gene (hpt) and neomycin phosphotransferase II gene (nptII) as selective markers. After 48 h of co-cultivation, the cells inoculated with A. tumefaciens strain LBA4404 (pTOK233) showed the highest GUS activity. After 4 months of subculture on the selection medium supplemented with 50 mg l(-1) hygromycin B, resistant calli appeared and adventitious shoots were regenerated 6 months after the transfer on B5 medium supplemented with 1 mg l(-1) BA. The presence of the gusA gene in the genome DNA of regenerated plants was detected by PCR and genomic Southern blot analysis. Leaf lam ina, another explant used for inoculation, rarely expressed transient GUS activity, and transgenic plants were not obtained. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.