Long-Term Cultivation of Digitalis lanata Clones Propagated in Vitro: Cardenolide Content of the Regenerated Plants1.

Shoot cultures of DIGITALIS LANATA Ehrh. (Scrophulariaceae) were established by inoculating meristem explants from axillary buds in a halfstrength liquid Murashige and Skoog medium. After short- and long-term cultivation IN VITRO, the shoots were rooted on a solid medium, transferred into soil, and grown in the greenhouse. The cardenolide content of the regenerated plants was determined by HPLC. The vegetatively propagated plants showed good homogeneity and are identical with the parent plant in terms of their digoxigenin-glycoside content. Long-term cultivation IN VITRO had no negative influence on the homogeneity and digoxigenin-glycoside content of the propagated plants. With this method, valuable genotypes can be preserved for a longer time than the natural vegetation period.