2002 Volume 19 Issue 2 Pages 135-139
The regeneration of multiple shoots from hypocotyl sections of Pittosporum tobira was studied on woody plant medium supplemented with differing concentrations of thidiazuron and naphthaleneacetic acid. Maximally 75% of hypocotyl sections formed multiple shoots when using the medium containing 10μM thidiazuron and 3.2μM naphthaleneacetic acid. Multiple shoots were transferred to a shoot-elongation medium followed by transfer to rooting medium. Plantlets formed were acclimatized, and complete plants were regenerated about 10 months after the initiation of the culture. A plasmid vector pANiR, which bears the cDNA of the nitrite reductase (NiR) gene from Arabidopsis thaliana under the control of cauliflower mosaic virus 35S promoter and nopaline synthase terminator, was introduced - together with pCH-bearing hygromycin resistance gene - into hypocotyl sections of Pittosporum tobira using a particle gun. A number of hygromycin-resistant calli were obtained, from which shoots were regenerated. The integration of Arabidopsis NiR cDNA into the genome of Pittosporum tobira was detected by the polymerase chain reaction method, confirming that these shoots were transgenic.
