Callus Culture of <i>Aralia cordata</i> Thunb.: Obtaining, Selection of Cultivating Conditions, Somatic Embryogenesis Induction

Abstract

Introduction. Cell cultures spreads widely in different areas of biology, biotechnology and agriculture. Aralia cordata is a perennial herbaceous plant, which has been listed in Red book of the Russian Federation. Pharmaceuticals which are based on raw materials of Aralia ssp. have valuable types of pharmacological activity and are widely used in oriental medicine. A serious obstacle for resumption of the natural populations is the presence of the period of morphophysiological dormancy in the seeds of the plants, which requires a long-time stratification process. Limitation of the natural geographic range and the combination of biological activities useful for humans make Aralia cordata Thunb. prospective object for in vitro introduction. Aim. The aim of the study is obtaining of the viable cell culture of Aralia cordata Thunb., investigation of the somatic embryogenesis conditions. Materials and methods. Pieces of the leaves of Aralia cordata intact plant from Komarov Botanical Institute of the Russian Academy of Sciences were used as a primary explants. Pieces of leaves were sterilized in a 2 % benzalkonium chloride solution for 5 minutes, induction of primary callogenesis was carried out on Murasige – Skoog medium. Nutrient media with different constituents were discovered for choosing one for long-time cultivation of calli. Induction of somatic embryogenesis was carried out on the nutrient media with high auxins content. Ethanol extracts from the intact plant and calli cultures were assayed with HPTLC PRO SYSTEM (CAMAG AG, Switzerland). Results and discussion. After two weeks of cultivation, the formation of primary callus was observed on the surface of the explants. The Linsmaier – Skoog medium with a reduced amount of sucrose (20 g/l) was recognized as the most suitable medium for long-term maintenance of cultures. Embryoid structures of Aralia cordata have been obtained, now we are continuing to collect analytics data about this process. Qualitative analysis of the extracts showed that callus cultures accumulate triterpene glycosides, their composition is close to that of the intact plant. Conclusion. A viable strain of callus culture of Aralia cordata Thunb. was obtained, a nutrient medium for long-term cultivation of calli was established. Somatic embryoids have been obtained, and their further development is currently being monitored. A preliminary phytochemical study showed that the composition of the chemical components of calli is close to that of an intact plant.