HIGH-FREQUENCY TRANSFORMATION FROM CULTURED COTYLEDONS OF ARABIDOPSIS-THALIANA ECOTYPES C24 AND LANDSBERG ERECTA

Procedures were developed for rapid and prolific adventitious shoot re generation of Arabidopsis thaliana (L.) Heynh ecotypes ''Landsberg ere ct'' and ''C24'' from cotyledon explants at 90-100% efficiency. Immatu re cotyledons had the highest shoot regeneration efficiency. Prolific regeneration was achieved in Murashige and Skoog medium (MS) supplemen ted with 0.1-0.4 mg(-1) naphthalene acetic acid (NAA) and 1.0 mg(-1) 6 -benzylaminopurine (BAP) within 2 weeks. The regenerated plants had a normal phenotype and produced fertile flowers and set seeds. The above regeneration protocol was used to develop a transformation method usi ng disarmed strains of Agrobacterium tumefaciens strains pGV3850::pH11 21 based on kanamycin (Km) selection. Transgenic shoots were produced within 2-3 weeks after inoculation. Transformation of shoots was confi rmed by GUS histochemical assay, as well as southern blot hybridizatio n.