In vitro Regeneration of Plantlets from Leaf and Nodal explants of Aristolochia indica L.- An Important Threatened Medicinal Plant

ABSTRACT

Objective: An efficient reproducible protocol has been developed for in vitro regeneration of plantlets from leaf and nodal explants of Aristolochia indica L. Methods: Wild grown plants Aristolochia indica L. were collected and grown in the departmental garden. Leaf and nodal segments (0.5-1.0 cm) from young healthy plants were first washed thoroughly under running tap water for 15 - 20 minutes and then treated with liquid detergent [5% (v/v) Tween-20] for 5-10 minutes. Later these explants were washed with double-distilled water for 5 minutes. Subsequently, explants were immersed in 70% (v/v) ethanol for 2 - 3 minutes and washed with sterile glass double distilled water for 2-3 times. Eventually, the explants were treated with an aqueous solution of 0.1% (w/v) HgCl2 for 1 - 2 minutes and rinsed for two-to-three times in sterile ddH2O to remove all traces of HgCl2. The sterilized explants were inoculated aseptically onto solid basal Murashige and Skoog’s medium with different concentrations and combinations of BAP and NAA for in vitro regeneration of plants. Results: Both leaf and nodal explants cultured on MS medium supplemented with 0.8 mg/L BAP developed into mass of callus. These calli were subcultured for the induction of shoots and roots. Shoots were induced from both calli on MS medium supplemented with 0.8 mg/L BAP+0.5 mg/L NAA. Roots were induced from in vitro shoots on MS medium supplemented with 0.8 mg/L NAA for 4 weeks. Nodal explants were more regenerative with 95 % response compared to leaf explants with 85%. Finally, these in vitro regenerated plantlets were hardened, acclimatised and successfully transferred to the field. Conclusions: The present protocol for in vitro regeneration of Aristolochia indica L. can be used to make this plant available throughout the year for traditional healers, pharmaceutical usages, germplasm conservation, commercial cultivation, and also for the production of secondary metabolites.