Abstract

An efficient and reproducible procedure is described for direct plant regeneration using in vitro regenerated leaf explants of Hypericum spectabile. The leaf explants were cultured on MS media supplemented with six different concentrations (0.25, 0.5, 1.0, 1.5, 2.0, 2.5 mg/L) of BAP and kinetin seperately. All of the BAP concentration, shoot regeneration occurred directly without callus formation, but the number of shoots changed, depending on the different concentrations of BAP. The highest and the lowest number of shoots were obtained on the medium supplemented with 1.0 and 2.5 mg/L of BAP (90 to 50%, respectively). In the present study, the medium containing 0.25, 0.5 and 2.5 mg/L Kin did not promote adventitious shoots formation. Among concentrations of Kin, the best results in terms of both shoots number and morphogenic properties were obtained from MS medium supplemented with 1.0 mg/L Kin (60%). In vitro regenerated plants induced roots on half-strength MS medium containing all the concentrations (0.25, 0.5, 1.0, 2.0 mg/L) of IAA. However, the medium supplemented with 0.5 mg/L IAA (100%) was found to be optimum for inducing root. Rooted 5- to 6-week-old in vitro regenerated plants were transferred into a greenhouse for acclimatization.

Key words: Hypericum spectabile, direct regeneration, leaf explant, in vitro, PGRs.