Callus induction and adventitious shoot regeneration of gardenia (Gardenia jasminoides Ellis) leaf explants

Leaves of gardenia (Gardenia jasminoides Ellis) were cultured on Murashige and Skoog [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco cultures. Plant Physiol. 15, 473-497.] medium (MS) supplemented with thidiazuron (TDZ, 0.1-10 mu M) and indoleacetic acid (IAA, 0.1-10 mu M). Callus production was highest at 10 mu M IAA, for each TDZ concentration. When these calli were transferred to MS medium supplemented with various levels of TDZ (5 or 10 mu M) and IAA (0.0, 0.1, 1, 5, or 10 mu M), the highest number of adventitious shoots (19.9 per callus) formed at 10 mu M TDZ plus 1.0 mu M IAA. A comparison of cytokinin activity showed that the best shoot proliferation was obtained from cultures treated with benzylaminopurine (BA), TDZ and zeatin (12.3, 15.2 and 19.2 per explant, respectively) compared with kinetin and 2iP (4.9 and 3.5 per explant, respectively) at concentrations of 15 mu M. The longest shoots were produced in cultures grown with either BA or 2iP at 2.5 mu M (38 and 43 mm per explant, respectively); those grown on TDZ, zeatin, and kinetin were shorter at 2.5 mu M (18, 20 and 25 mm per explant, respectively). The highest root number, longest roots, and highest rooting percentage occurred at the highest concentration of each auxin used. (C) 1998 Elsevier Science B.V.