In vitro medium-term conservation of Bacopa monnieri (L.) Pennell - The Memory Plus plant - under slow-growth conditions

摘要

A simple and efficient protocol was developed for in vitro slow-growth storage of shoot cultures for medium-term conservation of genetic resources of Bacopa monnieri (L.) Pennell. Shoot tips, nodal segments and multiple-shoot clumps could be stored for more than 20 months on solid Murashige and Skoog (MS) basal medium with 20 g L~(-1) sucrose and with no growth regulators, in polypropylene-capped culture tubes or culture bottles maintained at 24±2°C with a 12 hour dark + 12 hour light photoperiod with 35-40 mu mol m~(-2) s~(-1) irradiance. After storage, shoot multiplication was achieved in MS medium containing 0.5 mg L~(-1) of N6-benzyl adenine (BA). Shoot elongation and rooting were achieved in MS growth-regulator-free medium. The rooted plantswere successfully transferred to soil with 100% establishment. The plantlets stored could also be transferred directly from in vitro to nursery conditions, with 80% survival. The field-established plants were morphologically similar to mother plants. Using HPLC, comparative chemical profiling of mother plants and in vitro conserved plants (after establishment in the field) revealed similarity in the chemical profiles, indicating their chemical fidelity.