Shoot organogenesis from root-derived callus of Rhinacanthus nasutus (L.) Kurz. and assessment of clonal fidelity of micropropagted plants using RAPD analysis

Abstract

An efficient regeneration system was established for an ethnomedicinal shrub Rhinacanthus nasutus from root-derived callus organogenesis. The root segments were cultured on MS medium supplemented with various concentrations of Kn (1.0-4.0 μM) alone or in combination with IBA (0.2-0.6 μM) or 2, 4-D (0.5-1.5 μM). The optimum frequency (94%) of callus induction was recorded on MS medium supplemented with 3.0 μM Kn and 0.4 μM IBA. For shoot regeneration from callus, MS medium supplemented with different concentrations (1.0-7.0 μM) of BA or TDZ alone or in combination with NAA (0.2-1.0 μm) was employed. The highest frequency of shoot regeneration (91%) and mean number of shoots (28.3) were observed on MS medium supplemented with 5.0 μM BA and 0.7 μM NAA. The shoots were excised and cultured on MS medium with 4.0 μM IBA produced 3.4 roots per shoot in 88% cultures. Of the 65 plants transferred to soil 54 survived (83%). The plants were transferred to field after successful hardening. RAPD analysis of the regenerated plants showed high similarity with the mother plant.