Efficient in vitro regeneration of Artemisia annua: effect of different combinations of plant growth regulators on various types of explants

The global supply chain of artemisinin for treating malaria relies on the natural population of Artemisia annua. To enhance artemisinin levels in planta, genetic and molecular interventions, and clonal propagation through tissue culture is being explored worldwide. This investigation establishes an efficient protocol for in vitro regeneration by utilizing various plant growth regulators that have significant effects on plant development. Leaf and petiole explants of A. annua were cultured on MS media with different concentrations and combinations of plant growth regulators (PGRs). The highest frequency of callus development (96.13 +/- 0.89% response) was observed in explants cultured on MS medium supplemented with 1.0 mg l(-1) benzyladenine (BA) and 0.4 mg l(-1) thidiazuron (TDZ). The most effective regeneration medium for shoot formation from explants included 0.3 mg l(-1) 1-naphthaleneacetic acid (NAA) and 2.5 mg l(-1) BA, which resulted in a regeneration response of 88.90 +/- 2.48%. The MS medium supplemented with 2.0 mg l(-1) indole-3-butyric acid (IBA) and 0.5 mg l(-1) NAA demonstrated the highest root initiation from the regenerated shoots. These findings have the potential to contribute to the efficient in vitro regeneration of A. annua and facilitate the generation of genetically modified plants with improved artemisinin content.