A highly efficient method for carnation transformation

Transgenic carnation plants were produced using highly regenerative stem segments. The highest efficiency of adventitious shoot regeneration was obtained with segments originating from the stem's top internode. Transformation of cv. White Sim was performed with Agrobacterium tumefaciens carrying the binary vector pCGN7001 containing uidA and nptll genes encoding β-glucuronidase and neomycin-• phosphotransferase, respectively. Prior to inoculation, explants were wounded by microprojectile bombardment. Following selection in the presence of kanamycin, about 63 green shoots per 100 stem segments were recovered. Upon analysis, about 30% of these recovered shoots exhibited strong stable uidA expression throughout the plant. Thus the overall transformation efficiency was ca. 20%. The presence of the uidA and nptll genes in plants stable expressing uidA was confirmed by PCR and Southern blot analyses.