Direct regeneration of plants derived from in vitro cultured shoot tips and leaves of three Lysimachia species.

Abstract The regenerability of three ornamental species— Lysimachia christinae , Lysimachia rubinervis and Lysimachia nummularia ‘Aurea’, were investigated using in vitro leaves and shoot tips. 6-Benzylaminopurine (BAP) and α-naphthalene acetic acid (NAA) added to Murashige and Skoog (MS) medium were tested for their effect on organogenesis. On the medium, shoot regeneration occurred directly without callus formation. In these species, L. christinae developed the highest regeneration rate and numbers of shoots/explant from shoot tips (100%, 12.25) and leaf bases (100%, 13.01) on the MS medium containing 3.0 mg l −1 BAP and 0.1 mg l −1 NAA. For L. rubinervis , the highest shoot induction rate and number of shoots/explant were obtained from shoot tip (100%, 16.87–17.20) on the MS medium with 0.1 mg l −1 NAA and 3.0–5.0 mg l −1 BAP. L. nummularia ‘Aurea’, however, showed the highest regeneration rate and number of shoots/explant (100%, 12.73) from leaf bases on MS medium supplemented with 1.0 mg l −1 BAP and 0.1 mg l −1 NAA. All in vitro shoots rooted well on half macronutrient MS medium containing 0.1 mg l −1 NAA. After acclimatization, transplanted plantlets grew normally and flowered in the field.