Direct Somatic Embryogenesis of Two Iranian Native Orchid Species Using Protocorm Explants

In this study, direct soamtic embryogenesis of two Iranian native orchid species Dactylorhiza umbrosa and Epipactis veratrifolia via protocorm explants was investigated. In Epipactis veratrifolia, paclobutrazol ( PBZ) (0, 0.025, 0.05, 0.075 mg l-1) in combination with 2,4-D (0, 0.05, 0.1, 0.2 mg l-1) and thidiozoran (TDZ) (0, 1, 2, 3 mg l-1) were tested in 1/8 MS as basal medium and PBZ (0, 0.025, 0.045, 0.065, 0.1, 0.125 mg l-1) in combination with BA (0, 0. 5, 1.5, 3 mg l-1) were used in FAST medium for Dactylorhiza umbrosa. The results showed that in E. veratrifolia, 0.025 and 0.05 mg l-1 PBZ and 1 mg l-1 TDZ had highest embryogenesis rate with producing 11.33 means of embryos per explants. In other species, 0.045, 0.065 mg l-1 PBZ and 0.045 mg l-1 PBZ in combination with 1.5 mg l-1 BA had highest embryogenesis frequency with 4 embryos per explants. This is the first report about positive effect of PBZ on somatic embryogenesis in both orchid species. The Plantlets were transferred to hormone-free medium after six weeks.