Agrobacterium tumefaciens-mediated transformation of embryogenic tissue and transgenic plant regeneration in Chamaecyparis obtusa Sieb. et Zucc.

A genetic transformation procedure for Chamaecyparis obtusa was developed after co-cultivation of embryogenic tissues with disarmed Agrobacterium tumefaciens strain C58/pMP90, which harbours the sgfp (synthetic green fluorescent protein) visual reporter and nptII (neomycin phoshotransferase II) selectable marker genes. The highest transformation frequency was 22.5 independent transformed lines per dish (250 mg embryogenic tissue) following selection on kanamycin medium. Transgenic plantlets were regenerated through the maturation and germination of somatic embryos. The intensity of GFP fluorescence, observed under a fluorescence microscope, varied from very faint to relatively strong, depending on the transgenic line or part of the transgenic plant. The integration of the genes into the genome of regenerated plantlets was confirmed by Southern blot analysis.