Somatic Embryogenesis of Symplocos paniculata

Symplocos paniculata (Thunb.) Miq. (sapphire berry) is a deciduous shrub with showy white flowers and blueberry-like fruits. The fruit oil is used both as an edible oil and in the biodiesel industry. Plant regeneration via somatic embryogenesis is needed to provide source tissue for genetic transformation. Disinfested mature zygotic embryos were cultured on Murashige and Skoog (MS), modified MS (mMS), or woody plant medium (WPM) containing with 0.15, 0.2, 0.25, or 0.3 mg·L^-1 6-Benzylaminopurine (BAP) and 0.1 mg·L^-1 1-Naphthaleneacetic acid (NAA). Both medium and BAP significantly affected the callus induction. Twenty days after culture, calluses were induced on 64.6%, 85.1%, and 32.4% of explants that cultured on MS, mMS, and WPM, respectively. As BAP concentration increased, the callus induction rate quadratically increased. The highest induction rate, 92.5%, was observed on mMS plus 0.2 mg·L^-1 BAP and 0.1 mg·L^-1 NAA. To induce somatic embryos, calluses were cultured on mMS containing 0.2 or 0.25 mg·L^-1 BAP and 0.1, 0.15, or 0.2 mg·L^-1 NAA. Thirty days after culture, somatic embryos formed on 72.4% of calluses that cultured on mMS plus 0.25 mg·L^-1 BAP and 0.15 mg·L^-1 NAA. Somatic embryos were subcultured in the dark on the ½ mMS without plant growth regulator. Ten days after culture, 65% of somatic embryos formed shoots, which were still under test to develop roots.