Effect of nutrients and sucrose on microrhizome production and diosgenin accumulation in cultures of Costus speciosus Sm. in vitro

A simple and efficient protocol was developed for in vitro microrhizome induction in Costus speciosus. Maximum microrhizome formation was observed in full strength MS medium containing 80gl⁻¹ sucrose with an average of 3. 2g microrhizome per culture. Rhizome formation did not occur in different strengths of MS media (full, half and quarter) containing 2% sucrose. Effect of nutrients and sucrose on microrhizome production and diosgenin accumulation was analyzed. Maximum diosgenin content was recorded in microrhizomes produced in full strength MS medium containing 6% sucrose and least in quarter strength MS medium containing 8% sucrose.