A DNA fragment possessing ORF12 of TL-DNA of Ri(A4) plasmids (Slightom et al. 1986) was inserted into the genome of Nicotiana tabacum cv. Petite Havana SR1, through the binary vector system harbored by Agrobacteriumtumefaciens. The transformed plants showed dwarfness in plant height and corolla length. Adventitious roots were not induced from leaf disks by A. tumefaciens possessing ORF12.
