Plant Cell, Tissue and Organ Culture, cilt.162, sa.3, 2025 (SCI-Expanded)
The present study reports an effective in vitro propagation protocol for the endangered Verbascum bugulifolium Lam. through indirect organogenesis. The leaf explants taken from in vitro-grown seedlings were employed for callogenesis experiments. Murashige and Skoog (MS) medium supplemented with high concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) and 1-naphthaleneacetic acid (NAA) in combination with thidiazuron (TDZ) and 6-benzylaminopurine (BAP), respectively, induced the highest callus formation and growth rate. During callus formation experiments, all NAA treatments also induced organ formation. In the indirect organ formation experiments, the highest organ formation rate (93.33%) was recorded after BAP and indole-3-butyric acid (IBA) treatments at 1.0 mg L− 1 and 0.25 mg L− 1, respectively. The BAP treatment significantly promoted leaf proliferation by increasing the number of leaves to 8.26 from 0.53 per callus, while the IBA treatment resulted in root development with 2.2 roots per callus. The experiments on the rooting of indirectly formed leaves revealed that the IAA treatment at 0.5 mg L− 1 produced the highest number of roots (4.46 per indirectly formed leaf), while the control group had the longest roots (1.98 cm per indirectly formed leaf) and better new leaf development (7.4 newly formed leaves). No polymorphic bands indicating genetic instability were observed in the plants produced through indirect organogenesis. Well-rooted plantlets were acclimatized to soil, then transferred to field conditions. The methodology reported herein proposes a method for producing genetically stable clones of endangered V. bugulifolium for biodiversity conservation and medicinal uses in a sustainable manner.