EFFICIENT AGROBACTERIUM-MEDIATED TRANSFORMATION OF ARABIDOPSIS-THALIANA USING THE BAR GENE AS SELECTABLE MARKER

We have established an efficient Agrobacterium-mediated transformation procedure for Arabidopsis thaliana genotype C24 using the chimeric bi alaphos resistance gene (bar) coding for phosphinothricin acetyltransf erase (PAT). Hypocotyl explants from young seedlings cocultivated with agrobacteria carrying a bm gene were selected on shoot-inducing media containing different concentrations of phosphinothricin (PPT) which i s an active component of bialaphos. We found that 20 mg/l of PPT compl etely inhibited the control explants from growing whereas the explants transformed with the bm gene gave rise to multiple shoots resistant t o PPT after 3 weeks under the same selection conditions. The transform ation system could also be applied to root explants. Resulting plantle ts could produce viable seeds in vitro within 3 months after preparati on of the explants. The stable inheritance of the resistance trait, th e integration and expression of the bm gene in the progeny were confir med by genetic tests, Southern analysis and PAT enzyme assay, respecti vely. In addition, the mature plants in soil showed tolerance to the h erbicide Basta.