Comparison of direct and indirect regeneration in Eucalyptus microtheca M.

Seeds of E. microtheca were cultured on hormone-free MS medium cotyledons, then leafs and hypocotyls were separated from plantlets. All explants were cultured on modified MS medium with half-strength nitrate and supplemented with 12 different concentrations of NAA and Kin. Cultured explants were maintained in incubator with 16h light and 8h dark at 25°C and 19°C, respectively. The organs appeared after 4 weeks. The best medium for indirect regeneration of cotyledon and leaf tissues contained 4 mg l-1 NAA with Kin 0.5 mg l-1 and NAA 2 mg l-1 with Kin 1 mg l-1, respectively. In direct regeneration of hypocotyls, the best treatment contained 1 mg l-1 NAA with 1 mg l-1Kin. The frequency of regenerated samples showed that direct regeneration was better than indirect regeneration.