BIOLISTIC TRANSFORMATION OF ROSE (ROSA-HYBRIDA L.)

A reproducible method has been developed for the Biolistic transformat ion and regeneration of transgenic plants from embryogenic callus of r ose (Rosa hybrida L.) cv. Glad Tidings. DNA delivery was optimized usi ng the beta-glucuronidase (gus) gene. The distance between the stoppin g screen and target explants and supplementation of pre- and post-bomb ardment culture media with 0.25 M myo-inositol influenced the transfor mation efficiency. Prior to culture on selection medium containing 250 mg 1(-1) kanamycin sulphate, embryogenic calli were bombarded, using optimized gene delivery parameters, with a plasmid carrying the neomyc in phosphotransferase (npt II) gene. Somatic embryo-derived kanamycin- resistant plants were regenerated and subsequently transferred to glas shouse conditions. Transformation was confirmed by kanamycin resistanc e of calli and plants, NPT II ELISA assay and Southern analysis. All t ransgenic plants were morphologically normal (true-to-type). (C) 1998 Annals of Botany Company.