Promotion of callus initiation, shoot regeneration and proliferation in Lisianthus

The effects of plant growth regulators were examined in order to optimize the callus induction, regeneration, and proliferation of lisianthus (Eustoma grandiflorum). In vitro leaves provided the explants for callus induction. Explants were cultured on Murashige and Skoog (MS) medium with different concentrations of indole-3-acetic acid (IAA), 1-naphthaleneacetic acid (NAA), and 2,4-dichlorophenoxyacetic acid (2,4-D). Maximum callogenesis was obtained on MS medium supplemented with 100 μM NAA. Calluses were cultured on MS medium containing 6-benzyladenin (BA) (4.4, 13.3 or 22.2 µM) with or without 0.5 µM IAA and NAA for regeneration. The highest number of shoots (12.3 shoots/explant) developed on MS media with 22.2 µM BA plus 0.5 µM NAA. Individual shoots 1 cm in length were excised and multiplied. The maximal shoot proliferation with an average of 10.2 and 11.2 shoots/explant after 4 weeks of culture was achieved when the shoot tips were cultured on MS medium supplemented with 2.2 µM BA with or without 0.5 µM NAA. These results indicate that an efficient callus induction and micropropagation protocol of lisianthus had been established.