PERTANIKA JOURNAL OF TROPICAL AGRICULTURAL SCIENCE

The present report describes a comparative study for plant regeneration through callus morphogenesis in two different cultivars �CIM madhu� and �CIM mithi� of S. rebaudiana. The leaf explants were cultured on MS medium supplemented with IBA (1.0-4.0 mg/l) in combination with BAP (0.2 mg/l) for callus induction. Among the various tested combinations for shoot regeneration, maximum multiplication was recorded with MS + Kn (2.0 mg/l) + NAA (0.2 mg/l) + ADS (40 mg/l). Half-strength MS medium with IBA (0.2 mg/l) + AC (100 mg/l) was the best medium for the in vitro rooting of regenerated shoots. A comparison of different hardening media was also studied between two cultivars. The micro-plantlets hardened in plastic pots filled with sand: soil: vermiculite (1:2:1), covered with transparent polythene bags took minimum time to glass house transfer with maximum survival rate. CIM-madhu showed good callus induction, proliferation and regeneration ability in comparison to CIM-mithi. In comparison, higher rooting percentage was obtained in CIM-madhu with 97 % survival rate. The ability of �CIM-madhu� to induce callus and regenerate successful plantlets under these conditions suggests that this cultivar is moderately suitable for micropropagation purposes.