High frequency plant regeneration system for Nymphoides coreana via somatic embryogenesis from zygotic embryo-derived embryogenic cell suspension cultures

Culture conditions were established for high frequency plant regeneration via somatic embryogenesis from cell suspension cultures of Nymphoides coreana. Zygotic embryos formed pale-yellow globular structures and calluses at a frequency of 85.6% when cultured on half-strength Murashige and Skoog (MS) medium supplemented with 0.3 $mg\;l^{-1}$ of 2,4-D. However, the frequency of pale-yellow globular structures and white callus formation decreased slightly with an increasing concentration of 2,4-D up to 10 $mg\;l^{-1}$ with the frequency rate falling to 16.7%. Cell suspension cultures were established from zygotic embryo-derived calluses using half-strength MS medium supplemented with 0.3 $mg\;l^{-1}$ of 2,4-D. Upon plating onto half-strength MS basal medium, over 92.3% of cell aggregates gave rise to numerous somatic embryos and developed into plantlets. Regenerated plantlets were successfully transplanted into potting soil and achieved full growth to an adult plant in a growth chamber. The high frequency plant regeneration system for Nymphoides coreana established in this study will be useful for genetic manipulation and cryopreservation of this species.