High Frequency Plant Regeneration from Leaf, Petiole and Internode Explants of Codonopsis lanceolata Benth.

An efficient regeneration system was developed using leaf, petiole, and internode explants. Highly embryogenic callus was obtained following cultivation on MS basal nutrient supplemented with 2 2,4-D. Globular, heart, torpedo and cotyledon shaped somatic embryo were produced from the surface of embryogenic callus. Direct shoot regeneration without intermediate callus formation has been achieved on MS medium supplemented NAA and BAP. The percentage of response varies with different concentration of auxin and cytokinin treated individually or in combination. The best shoot regeneration response (54.28%) and number of shoot per explant (12.67) were achieved on the medium supplemented with 0.1 NAA and 1 BAP. The regenerated shoot transformed into young plant when cultured into elongation and root induction medium. More than 90% of in vitro propagated plants could survive when transferred to the greenhouse for acclimation. This optimized regeneration system can be used for rapid shoot proliferation and genetic transformation.