A HIGH-EFFICIENCY TECHNIQUE FOR THE GENERATION OF TRANSGENIC SUGAR-BEETS FROM STOMATAL GUARD-CELLS

An optimized protocol has been developed for the efficient and rapid g enetic modification of sugar beet (Beta vulgaris L.). A polyethylene g lycol-mediated DNA transformation technique could be applied to protop last populations enriched specifically for a single totipotent cell ty pe derived from stomatal guard cells, to achieve high transformation f requencies. Bialaphos resistance, conferred by the pat gene, produced a highly efficient selection system. The majority of plants were obtai ned within 8 to 9 weeks and were appropriate for plant breeding purpos es. All were resistant to glufosinate-ammonium-based herbicides. Detai led genomic characterization has verified transgene integration, and p rogeny analysis showed Mendelian inheritance.