Micropropagation of Dendrobium transparens L. from axenic pseudobulb segments.

摘要

An efficient protocol for micropropagation of Dendrobium transparens L. using the axenic pseudobulb segments, derived from in vitro germinated seedlings, was developed. The immature embryos from 120-d-old capsules after pollination were first germinated on half-strength Murashige and Skoog (MS) basal medium supplemented with 1 mg L-1 of naphthalene acetic acid (NAA)+2 mg L-1 of benzyl aminopurine (BAP). For multiple shoot induction, the axenic nodal segments excised from 120-d-old seedlings were cultured on the medium containing different concentrations and combinations of NAA and BAP. The multiplied shoots were then transferred to half-strength MS medium supplemented with 1 mg L-1 of indole-3 acetic acid (IAA) or indole-3 butyric acid (IBA) or NAA. Best response for shoot multiplication was achieved when the medium was supplemented with 1 mg L-1 NAA and 2 mg L-1 BAP, while that for rooting with 1 mg L-1 IAA. The plantlets were hardened off and more than 90% of survived plants were released to the shade house. The plantlets flowered 1 yr after transplantation.