Narrow-leaf firethorn or pyracantha (Pyracantha angustifolia (Franch.) C.K. Schneid.), from the family Rosaceae, is a species of large and thorny evergreen shrub. In this study, a procedure is presented for efficient axillary shoot multiplication and root induction in P. angustifolia using Murashige and Skoog (MS), woody plant (WPM), and Linsmaier and Skoog (LS) culture media supplanted with 6-benzylaminopurine (BAP) and indole-3-butyric acid (IBA). The disinfection of the axillary buds was performed with a 70.23% success rate on a basal MS medium augmented with 0.5 mg·L−1 gibberellic acid (GA3). Uniform and axenic explants were then cultured on MS, WPM, and LS media enriched with different concentrations of BAP, 0.3 mg·L−1 GA3, and 0.1 mg·L−1 IBA. The highest multiplication coefficient (2.389) was obtained for the MS medium supplemented with 2.5 mg·L−1 BAP. After one month, newly formed micro-shoots were transferred to rooting media (MS, WPM, and LS) containing different concentrations of IBA, together with a constant concentration of 0.1 mg·L−1 BAP. The micro-shoots were kept in the dark for one week and then cultured in a 16/8 h light/dark regime. The MS medium supplemented with 1 mg·L−1 IBA was the most effective in stimulating rooting (88.76% of micro-shoots). The highest number of roots (3.5 per micro-shoot) was produced in the MS medium enriched with 1.5 mg·L−1 IBA. The rooted plantlets were transferred into pots filled with perlite and peat moss in a 2:1 proportion and acclimatized to ambient greenhouse conditions, with a resultant mean 92.84% survival rate. Thus, this protocol can be successfully applied for the in vitro mass propagation of P. angustifolia.

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