Efficient regeneration of plants from shoot tip explants of Dendrobium densiflorum Lindl., a medicinal orchid

摘要

Dendrobium densiflorum?Lindl. is one of the horticulturally important orchids of Nepal due to its beautiful yellowish flower and medicinal properties. The present study was carried out for plant regeneration from shoot tip explants of?D. densiflorum?by tissue culture technique. The shoot tip explants of this species, obtained from?in vitro?grown seedlings were cultured on Murashige and Skoog (MS) media alone and MS medium supplemented with different combination and concentration of 6-benzylaminopurine (BAP) and napthalenacetic acid (NAA). The maximum number of healthy shoot was observed on MS+ BAP (2 mg/l) + NAA (0.5 mg/l) (4 shoots/ culture). The shoot multiplication started after three weeks of culture. The induction of root was observed on all MS medium supplemented with different concentration and combination of plant growth regulators?[indole-3-acetic acid?(IAA),?indole-3-butyric acid?(IBA) and NAA]. For inducing root, MS media without and with auxins (IAA, IBA and NAA) were used. Among these, the most effective condition for?in vitro?rooting was observed on MS+ IBA (1.5 mg/l). The?in vitro?propagated plantlets were transferred in 2:1:1 ratio of cocopeat, litter and clay containing earthen pot for acclimatization. About 85% plantlets were successfully acclimatized in the greenhouse of Central Department of Botany, Kirtipur.