Abstract

Gynura bicolor DC. is a perennial vegetable and medicinal plant. It is an important source of anthocyanins. The effects of different growth regulators on callus induction and plant regeneration were evaluated. The best SFC index (8.6) of plant regeneration was obtained in combination of 2,4-D at 2.0 mg/l and BA at 0.5 mg/l, and the frequency of regenerating explants was 78.3%. The highest number of shoots per explant was 11. The genetic stability of the regenerants was analyzed by random amplified polymorphic DNA (RAPD), inter-simple sequence repeat (ISSR) molecular markers and flow cytometry. The results indicated that no somaclonal variation was detected among the regenerants. To our knowledge, this is the first report of somatic clone study in G. bicolor. The high efficient and reproducible protocol will be advanced for the further studies on secondary metabolic products, transformations and breeding of this potential medicinal plant.

Key words: Flow cytometry analysis, genetic stability, Gynura bicolor, inter-simple sequence repeat (ISSR), random amplified polymorphic DNA (RAPD), regeneration.

Abbreviation

BA, 6-Benzylaminopurine; MS, Murashige and Skoog (1962) medium; NAA, a-naphthalene acetic acid; TDZ, thidiazuron; 2,4-D, 2,4-dichlorophenoxyacetic acid; KT, kinetin; IBA, indole 3-butyric acid; AgNO₃, silver nitrate; CTAB, cetyl trimethylammonium bromide; ISSR, inter-simple sequence repeat; RAPD, random amplified polymorphic DNA; FCM, flow cytometry.