Efficient micropropagation and rooting of Micromeria croatica (Pers.) Schott (Lamiaceae)

Abstract

Micromeria croatica is an endangered species with a great potential for use as a medical as well as ornamental plant. For commercial use, an efficient propagation protocol is required. The aims of this study were to establish an efficient protocol for micropropagation and rooting of M. croatica. A number of factors were tested including the influence of 6-benzylaminopurine (BAP) and 1-naphthaleneacetic acid (NAA) at different concentrations as well as the effect of explant orientation and topophysis on shoot proliferation. Rooting was investigated in agar-based medium supplemented with indole-3-butyric acid (IBA) or indole-3-acetic acid (IAA) at various concentrations. Media with 1 and 2 mg/L of BAP produced the highest number of shoots/explant. However, the lower concentration of BAP should be recommended due to longer shoots without any sign of hyperhydration. Explant orientation and node position showed equal capability for shoot proliferation. Importantly, 100% efficiency of rooting was achieved in an agar-based rooting medium. Acclimatisation exceeded 90%. Taken together, an efficient protocol for micropropagation and rooting of M. croatica has been established for future production.