<Emphasis Type="Italic">In vitro</Emphasis> plant regeneration,flowering and fruiting from nodal explants of <Emphasis Type="Italic">Andrographis lineata</Emphasis> nees (Acanthaceae)

In the present study, in vitro propagation of tribal endemic medicinal plant, Andrographis lineata has been established using mature nodal explants. High frequency of regeneration (91.4%) was achieved on MS medium containing BA (3.0 mg L^–1) along with IAA (0.2 mg L^–1). Strikingly, irrespective of the season and collection period, we observed axillary flower induction and fruit formation from the above in vitro cultures supplemented with BA and NAA. Transition from the vegetative to the reproductive phase occurred within 2 months of culture, and importantly was influenced by factors such as sucrose and cytokinins. In vitro-regenerated flowers were morphologically identical to in vivo flowers. Furthermore, our scanning electron microscopic studies revealed that pollen external morphology of both in vitro and in vivo flowers were similar. The flowers self-fertilized and produced fruits in vitro. Elongated shoots rooted well on half-strength MS basal medium, and were successfully acclimatized to the garden conditions. Altogether, our established protocol can be utilized in plant breeding for the purpose of ex situ conservation, quick flowering, and fruit set.