In vitro methods provide a variety of tools to supplement traditional methods for collection, propagation and preservation of endangered plant species. In this study, an efficient protocol was developed for in vitro propagation of Colutea gifana, a rare and endangered plant species with limited reproductive capacity that grows in a narrow area of Iran. Single node explants were used for a series of experiments to select the appropriate disinfection method and growth regulators for establishment, proliferation and rooting stages. Explants showed the highest establishment percent after treatment with 2% Sodium hypochlorite (NaOCl) for 15 min, cultured in MS medium containing 2.2 µM 6-benzylaminopurine (BA) and 1 µM indole-3-butyric acid (IBA). In proliferation stage, 8.8 µM of BA was more effective cytokinin than Kinetin (Kin) and Thidiazuron (TDZ) for growth induction of axillary shoots. In vitro rooting of proliferated shoots was induced in half-strength MS medium in all concentrations of both tested auxins i.e. IBA and α-naphthalene acetic acid (NAA). Eighty percent of the plantlets were successfully acclimatized to ex vitro conditions, showed normal development. These plantlets were used to replenish declining populations in the wild and conserve C. gifana from extinction.

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