An efficient system for inducing somatic embryogenesis in Panax notoginseng was established using shaker flasks and bioreactor cultures;furthermore, regenerated plantlets were successfully transferred to ex vitro soil conditions.Embryogenic callus was induced from segments of adventitious roots incubated on Murashige and Skoog (MS) medium containing 1.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) after 5 weeks of culturing.The highest frequency (100%) of somatic embryogenesis, with a mean of 32.7 somatic embryos per callus, was obtained on embryogenic callus incubated on a medium containing 0.5 mg/L 2,4-D.To scale-up somatic embryo formation, 10 g (*1.65 9 104) of early globular-stage somatic embryos were incubated in a 3 L airlift bioreactor containing 1.5 L 1/2 MS medium without plant growth regulators (PGRs) for a period of 4 weeks;these globular-stage somatic embryos then developed into cotyledonary embryos.When maintained on PGR-free medium, the cotyledonary embryos developed roots but did not develop shoots.However, when they were treated with gibberellic acid (GA3), they continued to germinate and transformed into plantlets after 2 weeks of culture.Plantlets with welldeveloped shoots and roots were transferred to an autoclaved vermiculite and perlite mixture, acclimatized for a period of 3 months and successfully transferred to forest mountain soil.Following overwintering, these plants produced new growth.