Transformation of Catalpa ovata by Agrobacterium rhizogenes and phenylethanoid glycosides production in transformed root cultures

Transformed root cultures of Catalpa ovata were established following shoot s infection with four agropine strains of Agrobacterium rhizogenes. Frequen cy of root formation was dependent on the bacterial strain and the presence of acetosyringone in the incubation medium. It is the first report concern ing the possibility of transforming Catalpa ovata by A. rhizogenes. Both tr ansformed and untransformed root cultures of C. ovata were studied for thei r growth and phenylethanoid glycoside production. As with the roots of inta ct plants, cis-and trans-verbascoside as well as martynoside were produced in transformed and untransformed root cultures of C. ovata. In hairy roots, total (cis + trans) verbascoside production could be stimulated up to thre e-fold of that of roots of 6-month-old plants grown in a greenhouse, by usi ng an appropriate root line cultured in liquid (1)/(2) B5 Gamborg medium co ntaining indole-3-butyric acid (0.1 mg/l) in the dark but not light conditi ons. Transformed and untransformed root cultures of C. ovata were also foun d to have 10 times higher martynoside production than roots of intact plant s.