Genetic transformation of gentian using wild-type Agrobacterium rhizogenes

Agrobacterium rhizogenes A4 harboring the agropine type root-inducing plasmid (pRiA4) induced hairy roots on stem sections of gentian plants. Transgenic gential plants were regenerated from the hairy roots at a frequency of 19% adventitious shoot regeneration on Murashige and Skoog medium containing 30 g l(-1) sucrose, 10 mg l(-1) N-phenyl-N'-1,2,3-thiadiazol-5-yl urea, 1 mg l(-1) 1-naphthaleneacetic acid and 2 g l(-1) gellan gum. The shoots were grown to maturity in a growth chamber after acclimatization. The mature transformed plants showed distinct variations in their phenotypes, such as dwarfness. Polymerase chain reaction and Southern blot analysis revealed stable integration of transferred DNA.