Abstract: INTRODUCTION: Ajania alabasica is a wild species of the genus Ajania in the Asteraceae family, characterized by its remarkable drought resistance and ecological adaptability, making it a valuable genetic resource for breeding. Nevertheless, the absence of an effective in vitro regeneration system has impeded the advancement of rapid propagation and genetic transformation studies on this species.  RATIONALE: The utilisation of appropriate explants constitutes a critical strategy for plant regeneration. The core of this methodology lies in optimizing the combinations of plant growth regulators (PGRs) and additives to balance differentiation and physiological disorders such as hyperhydricity. This study was conceived with the objective of systematically determining the effects of different explant types (leaves vs. stem segments) and PGRs, with a view to establishing a robust regeneration protocol for A. alabasica.  RESULTS: This study found that leaf explants exhibited significantly higher regeneration potential than stem segments. The results demonstrated that the optimal medium for callus induction and adventitious bud differentiation from leaves was MS basal medium supplemented with 1.0 mg∙L^–1 6-BA and 1.0 mg∙L^–1 NAA. Following the culture period, this resulted in a callus induction rate of 100% (at 15 days) and an adventitious bud differentiation rate of 92.22% with a multiplication coefficient of 6.93 (at 30 days). To address hyperhydricity, the optimal proliferation medium was identified as containing 0.3 mg∙L^–1 6-BA and 0.05 mg∙L^–1 NAA, with 5 µmol∙L^–1 AgNO3 proving effective for alleviation. For the rooting phase, the optimal medium was identified as 1/2MS medium supplemented with 0.2 mg∙L^–1 NAA, which resulted in a rooting rate of 100% and a transplant survival rate of 88%.  CONCLUSION: This study successfully established for the first time a highly efficient and stable regeneration system for A. alabasica using leaf explants. The developed system, characterized by its high differentiation and survival rates, provides crucial technical support for subsequent genetic transformation and gene function analysis.

Key words: Ajania alabasica,  regeneration system,  vitrification