In vitro organogenesis from Tinospora cordifolia (Willd.) Miers - A highly valuable medicinal plant

Efficient in vitro regeneration protocols were established for Tinospora cordifolia through direct and indirect organogenesis, using cotyledon (C), young leaf (YL) and mature leaf (ML) explants. Highest response of 97.9-100.0% organogenic callus was induced on Murashige and Skoog (MS) medium containing indole-3-acetic acid (IAA) at 2.0 mg/L. Morphology of the callus varied from yellow friable to compact on auxin treatments. Shoot bud induction from callus was rapid on modified MS medium (mMS) containing IAA or 1-naphthalene acetic acid (NAA) with 6-benzyladenine (BA), kinetin (KN) and ascorbic acid (AA). Among the explants, cotyledons produced the highest shoot number (24.1 shoots) followed by YL (19.0) and ML (16.1) explants. Direct organogenesis was better on C than YL explant. Highest of 14.5 and 11.0 shoots were achieved on BA, KN, AA and IAA (0.5 mg/L) from C and YL explants, respectively. Best shoot length of 8.3 cm was achieved on MS medium containing gibberellic acid (GA3) at 0.5 mg/L. All the shoots were rooted on MS medium at half strength macro salts (½ MS) with indole-3-butyric acid (IBA) 0.5 mg/L and NAA 0.5 mg/L. Rooted plantlets were successfully hardened under in vitro conditions and transferred to the glasshouse with 75% survival rate. This is the first report on successful organogenesis via callus and from different explants in T. cordifolia. The same protocols using different medium and plant growth regulators (PGRs) at different stages of organogenesis can be utilized for mass production to aid commercial needs and eco-restoration of this plant and to the related genera.