In vitro seed germination of Cymbidium aloifolium (L.) Sw., a potential medicinal Orchid from Eastern Ghats of Tamil Nadu, India

Cymbidium aloifolium (L). Sw. is an exquisite epiphytic orchid of the Kolli Hills (Eastern Ghats) of Tamil Nadu in Southern India. It is fast disappearing from its natural habitats due to deforestation and low germination rate in natural habitat. In the present study, an attempt was made to germinate the seeds from un-dehisced capsule of Cymbidium aloifolium (L). Sw under in vitro condition. The seed germination and protocorm development were recorded in three different well known media namely Knudson C (KC), Half strength Murashige & Skoog (1/2 MS) and Vacin & Went (VW) media. The highest seed germination of 90% was observed KC basal media after 30th days whereas germination percentages were 40% and 30% on 1/2 MS and VW media respectively. The well-developed protocorm were transferred to KC media supplemented with 6-Benzyl Amino Purine (BAP) and Naphthalene acetic acid (NAA) where BAP (1.0 mg/l) and NAA (1.0 mg/l) together were found to be optimum for the highest shoot formation. About 90% of the shoots found to be well rooted after transfer to the KC medium differently supplemented with 1.5 mg/l Indole-3-acetic acid (IAA) and 1.0 mg/l Indole-3-butyric acid (IBA). Though rooting also took place in the two basic media but the duration was longer when compared with the hormone-supplemented media. The rooted plantlets were hardened and kept under greenhouse conditions which can be relocated in natural habitats.