Efficient in Vitro Plant Regeneration

An efficient plant regeneration system for Pinellia ternata (Thunb) Breit, an important wild Chinese herb, was established. The investigated factors influencing callus induction and plant regeneration included sterilizing agents, explant type, culture medium, and combinations of plant growth regulators in the medium. Ten min treatment of explants with 0.1% HgCl2 was more suitable for sterilization of tuber explants than NaClO and H2O2. Tubers as explants were superior to leaves and petioles, and MS medium was better than N6 and White’s media. It was found that 9.1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) plus 4.4 μM 6-benzyladenine (BA) in the medium was the best hormone combination for promoting callus induction. The highest shoot regeneration frequency (99%) was achieved from callus cultured on MS medium supplemented with 9.3 μM kinetin (KN) and 2.3 μM 2,4-D. The rooted shoots were successfully transplanted in soil, with over 95% survival. Establishment of an efficient plant regeneration procedure provides a basis for rapid in vitro propagation of P. ternata, which is in great demand in China, and represents an excellent tool for further work on its genetic manipulation.