Callus induction, direct and indirect organogenesis of ginger (Zingiber officinale Rosc)

The present study aimed to induce callus, direct and indirect organogenesis of ginger (Zingiber officinale Rosc) by using Murashige and Skoog (MS) medium fortified with different concentrations and combinations of growth regulators. Shoot tip, in vitro leaf and root segments were used as explants to induce callus by MS medium containing (0.00 as control, 0.5, 1.00, 2.00 and 3.00 mg/L) of 2,4-dichloro-phenoxyacetic acid (2,4-D). Callus induced was subcultured on MS+2,4-D at different concentrations (0.5, 1.00, 2.00 and 3.00 mg/L) and one concentration 0.5 mg/L of 6-benzyl amino purine (BAP) was used. The sprouting buds (about 1 to 1.5 cm) were used as explants for direct shoots and roots induction by MS medium + 2.00, 3.00 and 4.5 mg/L of BAP. Callus induced by 1.00 mg/L 2,4-D was regenerated on MS + 0.5 mg/L 2,4-D to obtain a green callus, this callus was transferred to MS medium with combinations of 0.5 mg/L 1-naphthaleneacetic acid (NAA) with different concentrations of BAP (1.00, 2.00,3.00 and 4.00 mg/L) for indirect organogenesis. The results reveals that, for callus induction, callus was only induced from shoot tip explant in all concentrations of 2,4-D. The highest callus fresh weight was obtained by 1.00 mg/L of 2,4-D (1.302 ± 0.09) g than that induced by other treatment (p < 0.05). In the case of callus induced by subculture, the highest callus fresh weight initiated was 1.509 ± 0.00 g by 0.5 mg/L 2,4-D. For direct organogenesis, 4.5 mg/L BAP showed the highest number of in vitro shoots and roots, 4 ± 0.35 shoots and 15 ± 0.46 roots per explants. For indirect organogenesis, the best shoots and roots initiated were 2 ± 0.21 shoots and 22 ± 0.33 roots by combination of 1.00 mg/L BAP+0.5 mg/L NAA. Key words: Callus induction, growth regulators, Zingiber officinale Rosc, organogenesis.