Establishing an efficient micropropagation method for Huang Qi (Astragalus membranaceus)

Abstract Astragalus membranaceus is known as Hwang-gi in Korea, Huang Qi in Chinese and Radix Astragali in Latin, is a member of Fabaceae family. Traditionally, it has been used as an immunomodulator to treat people with cardiovascular disease as well as colds, fatigue, diarrhea, anorexia, and irregular uterine hemorrhage. In this study, an efficient micropropagation method of Huang Qi was established, by which micropropagation can be achieved from 2 pathways: directly and indirectly. For direct organogenesis, the multi-shoots were induced from apical or lateral shoots in MS medium with BA at 1.0 mg/L and subsequently, they were proliferated in MS supplemented with kinetin at 2.0 mg/L. For indirect organogenesis, the adventitious shoots were regenerated indirectly in MS with BAP at 1.0 mg/L and IBA at 0.5 mg/L media from callus, formed in MS with 2.4-D at 1.0 mg/L. Finally, the single shoot was transferred to 1/2 MS medium for rooting. Regenerated plants grown on hormone-free media for 1 month were transferred to polyethylene pots containing a cocopeat: perlite (3:1; v/v) mixture with a survival rate of approximately 93% 1 month after acclimation. The results of this study make a significant contribution to the efficient micropropagation of this plant, which is useful to provide abundant and stable resources for the extraction of secondary metabolites with potential downstream applications. Large-scale micropropagation offers an alternative within shorter time to grow this plant in the field for commercial and pharmaceutical uses.