Trichomes and regeneration by direct organogenesis of medicinal plant Dracocephalum kotschyi L. using shoot tips (Lamiaceae)

The present study describes the procedure for micropropagation of Dracocephalum kotschyi L. using shoot tips from in vitro-germinated plants. The best response was observed for shoot tips on MS medium containing 5 mg 6-benzylaminopurine L^?1 and 0.2 mg 1-naphthaleneacetic L^?1 acid. Regeneration for other types of the explant hypocotyls and cotyledons did not show satisfactory results so that the explants did not develop into normal shoots and in turn developed into the calli after 12 days of culture. Histochemical analysis showed that only the shoot tip revealed a direct induction of more teratological protuberances that arise around the cut end of the explants. Elongation of shoot buds was obtained on MS medium containing 1 mg BAP L^?1 + 0.5 mg IBA L^?1. Regenerated shoots rooted best on the same medium of elongation. After hardening, the rooted plants were transferred to the greenhouse where they grew, matured, and flowered normally with a survival rate of 95%. We concluded that the present protocol can be efficiently used for mass propagation of Dracocephalum kotschyi.