Agrobacterium-mediated transformation of a doubled haploid line of cabbage

Doubled haploid lines, which have high levels of genetic uniformity, are suitable for physiological or genetic studies. We established a transformation system using a doubled haploid line of cabbage. Hypocotyl explants that had been precultured for 3 days on Murashige and Skoog medium containing 50 µM acetosyringone were inoculated and cocultured with Agrobacterium tumefaciens strain LBA4404 (pIG121Hm) for 3 days. Kanamycin-tolerant shoots were regenerated onto shoot induction medium 3 months after Agrobacterium inoculation. The transformation efficiency was about 3% under optimal conditions. The segregation pattern of the self-pollinated transformant that carried one copy of the introduced transgene revealed that the β-glucuronidase gene was inherited in a 3:1 ratio.[PUBLICATION ABSTRACT]