Enhanced shoot organogenesis in Cassia angustifolia Vahl. - a difficult-to-root drought resistant medicinal shrub

In vitro regeneration was achieved through callus culture derived from cotyledon explants of Cassia angustifolia Vahl. on MS (Murashige and Skoog, 1962) medium. Calli were induced from cotyledon explants excised from aseptic 14 days old seedlings on MS medium containing 2,4-D (2,4-dichlorophenoxy acetic acid) and 2,4,5-T (2,4,5-trichlorophenoxy acetic acid) at different concentrations with 3% sucrose and 0.8% agar. Optimal growth of callus was obtained at 5.0 mu M 2,4-D, which was proved to be the best for shoot regeneration when sub cultured onto MS medium supplemented with cytokinins either alone or in combination with an auxin. Maximum number of shoots (23.2 +/- 1.4) were produced at 5.0 mu M 6-benzylaminopurine (BA) and 0.4 mu M alpha-naphthalene acetic acid (NAA). Regenerated shoots produced prominent roots when transferred to half strength MS medium supplemented with 1.0 mu M indole-3-butyric acid (IBA) and 5.0 mu M phloroglucinol (PG). Rooted plantlets thus developed were hardened and successfully established in the soil. This protocol yielded an average of 23 plants per cotyledon explant over a period of 4 months.