Bulgarian golden root in vitro cultures for micropropagation and reintroduction

Abstract

Abstract Rhodiola rosea is an endangered medicinal plant used for cancer, cardiovascular, and nervous system diseases therapy. Due to its limited distribution and sustainability alternative methods for production of its valuable substances are under investigation. Using in vitro techniques apical and rhizome buds, leaf nodes, stem and radix segments from wild plants and in vitro seedlings were plated on 24 modified Murashige and Skoog (1962) media. Decontamination of plant material was successful only in 21% of the schemes. The best shoot induction was obtained from seedling explants on media containing 2 mg/l zeatin or N6-benzylaminopurine, each. Their reduction stimulated shoot formation in the next passages (multiplication rate up to 5). Efficient rooting was induced on half-strength MS with 2 mg/l Indole-3-butyric acid and stimulated by adding 0.2 mg/l Indolyl-3-acetic acid. Regenerants rooted in perlite, peat, and soil (1:1:2), adapted in greenhouse, and transplanted in the mountains survived (70%) and developed like the wild plants. Salidroside content of these plants after one or two years was high (0.64 and 0.61% in rhizomes and 0.62 and 0.53% in roots, respectively). This is the first established efficient scheme for micropropagation of Bulgarian R. rosea allowing habitats restoration, germplasm conservation, and potential application of biotechnology for production of valuable substances.