Micropropagation of Ocimum kilimandscharicum Guerke (Labiatae)

Abstract

An efficient plant regeneration protocol has been developed from nodal explants of Ocimum kilimandscharicum Guerke, a medicinally important herbaceous plant species belonging to the family Lamiaceae. Axillary shoot bud proliferation was initiated from nodal explants cultured on MS medium supplemented with various concentrations of 6-benzyladenine (BA) (0.5–3.0 mg/l), kinetin (KN) (0.5–3.0 mg/l) and 2-isoPentenyladenine (2-iP) (0.5–3.0 mg/l). The maximum number of shoots (6.09±0.05), with average length 3.83±0.11 cm, was achieved with medium containing 1.0 mg/l BA. Shoot culture was established by repeated subculturing of the original nodal explants on shoot multiplication medium after each harvest of newly formed shoots. In this way, 20–30 shoots were obtained from a single nodal explant after 5 months. Rooting of shoots was achieved on half-strength MS medium supplemented with 1.5 mg/1 Indole-3-butyric acid (IBA) and 2% sucrose. Well-developed plantlets transferred to plastic pots containing soil and vermiculite (1:1) showed 81.13% survival. The genetic fidelity of in-vitro-raised field-grown plants to the donor plant was ascertained from random amplified polymorphic DNA (RAPD) markers. This protocol can be used for commercial propagation and for future genetic improvement studies.