Micropropagation of Stevia rebaudiana Bertoni. through direct and indirect organogenesis

Abstract

The present research work was undertaken to develop a protocol for micropropagation of Stevia rebaudiana Bertoni., an important medicinal plant of Bangladesh. Shoot apex, Leaf and Nodal explants were aseptically cultured on agar solidified Murashige and Skoog (MS) medium supplemented with different growth PGRs (Plant growth regulators). Indirect organogenesis was found in leaf segment and direct organogenesis was observed in shoot apex. But in case of nodal segment both direct and indirect organogenesis were found. Maximum amount of green compact callus produced from nodal explants in MS medium supplemented with 1.0mg/l benzylaminopurine (BAP) + 0.5mg/l indole-3-acetic acid (IAA). The induced calli were cultured on MS medium fortified with different PGRs for shoot proliferation. The maximum number of shoot buds (15.30 ± 0.15) formation was observed in MS medium fortified with 1.5mg/l BAP+0.5mg/l IAA. Multiple shoot buds underwent rapid elongation on elongation media and maximum elongation (6.90 cm) took place on MS with 1.0 mg/l BAP + 1.0 mg/l IAA. Elongated shoot buds produced strong and stout roots (4.40 cm) on half strength MS medium fortified with 1.0 mg/l indole-3-beutyric acid (IBA). The well developed plantlets were successfully transferred to hardening and survival rate was 95%.