Development of robust in vitro culture protocol for the propagation of genetically and phytochemically stable plants of Withania somnifera (L.) Dunal (Ashwagandha)

Withania somnifera (L.) Dunal is an important medicinal plant that has gained a lot of attention since ancient times due to its immense pharmaceutical potential. Scientific validations of its therapeutic potential against many diseases have immensely increased its demand in the domestic and international market. Thus, to narrow down the huge gap between its demand and supply, alternative strategies to conventional cultivation are required. In vitro propagation system provides a feasible option for the production of large-scale healthy, genetically and phytochemically uniform W. somnifera plants to boost the herbal industry and facilitate preclinical studies. However, the major challenge in in vitro propagation of W. somnifera is to maintain a high rate of shoot multiplication for prolonged periods in cytokinin containing MS medium. In the current investigation, for prolonged maintenance of in vitro shoots, a multi-step protocol involving the rotational subculture of Withania shoots in the auxin-cytokinin containing culture medium has been developed to minimize the adverse effects of cytokinin. In vitro shoots after prolonged subculture were checked for genetic uniformity and stable pharmaceutically important constituents. Furthermore, in vitro rooting was initiated either in an auxindependent or auxin-independent manner through modulation of ammonium nitrate strength. Hence, the protocol developed for in vitro propagation of W. somnifera is cost-effective and can be efficiently used for the industrial production of withanolides.

Automated summary

Withania somnifera is a medicinal plant with immense pharmaceutical potential. In vitro propagation system is used to produce genetically and phytochemically uniform plants, with a multi-step protocol developed to minimize the adverse effects of cytokinin. The protocol also includes modulation of ammonium nitrate strength for in vitro rooting initiation.