Author(s)

Rajae Benkaddour¹, Naouar Ben Ali¹, Ouafaa Hamdoun¹, Alain Badoc², Latifa Azaroual³, Patrick Martin⁴, Ahmed Lamarti¹

¹Laboratory of Plant Biotechnology, Biology Department, Faculty of Sciences, Abdelmalek Essaadi University, Tetouan, Morocco.
²Laboratoire MIB (Molécules D’Intérêt Biologique), ISVV (Institut des Sciences de la Vigne et du Vin), UMR OENO, Université de Bordeaux, Villenave-d’Ornon, France.
³Water Laboratory, Environmental Studies and Analyzes (L2EAE), Department of Chemistry, Faculty of Science, Abdelmalek Essaadi University, Tetouan, Morocco.
⁴Université d’Artois, UniLaSalle, Unité Transformations & Agroressources, Béthune, France.

Origanum vulgare L. is a commercially valued species with remarkable biological properties. It is subject to over-exploitation practices that seriously threaten its sustainability for future generations. Thus, micropropagation serves as a tool for the protection and domestication of this species. In this study, we established an in vitro vegetative propagation protocol for Origanum vulgare. This is done through the axillary bud technique by carrying out various tests. Six culture media (MS, MSm, N₃₀K, SD, SH and B5) were tested. Therefore, SD was chosen for the following experiments. Seven cytokinins (adenine (Ad), N6-(2-isopentenyl) (2ip), zeatin (Zeat), kinetin (Kin), benzyladenine (BAP), 1,3-diphenylurea (DPU) and thidiazuron (TDZ) at 5 concentrations (0.44, 1.33, 2.22, 3.11 and 4.44 μM/L) were evaluated. Thus, Kin at 3.11 μM allowed high regeneration of vitroplants, optimal elongation, total rooting of explants, maximum bud multiplication, and absence of hyperhydric explants. In fact, the integration of auxins (indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), and 1-naphthaleneacetic acid (NAA)) into the culture medium and their combinations with 3.11 μM Kinetin contributed to the optimization of the root part. Thus, it was improved in particular in the case of 3.11 μM Kin and 6.27 μM IBA. Three polyamines (Putrescine, Spermidine and Spermine) at different concentrations (1.134, 3.402, 5.67, 7.938 and 11.34 μM/L) combined at 3.11 μM Kin and 6.27 μM IBA were tested. In fact, 1.304 μM putrescine was considered to be the most suitable for in vitro culture of explants, since it allowed optimal propagation of buds and roots, also a high rate of regeneration and rhizogenesis. GA₃ at 1.15 μM combined with 3.11 μM Kin and 6.27 μM IBA permitted maximum bud multiplication. The acclimatization was carried out successfully using vitroplants showing good foliar and root development. Thus, three months after acclimatization, the seedlings were transferred into large pots under natural light and temperature conditions. Almost all acclimatized plants developed flowers in the first year between May and July.

Auxins, Cytokinins, Gibberellic Acid, Macronutrients, Micropropagation, Polyamines, Origanum vulgare

Benkaddour, R. , Ali, N. , Hamdoun, O. , Badoc, A. , Azaroual, L. , Martin, P. and Lamarti, A. (2022) Micropropagation and Acclimatization of Common Oregano (Origanum vulgare L. Subsp. vulgare) by Shoot Tip Culture. American Journal of Plant Sciences, 13, 833-855. doi: 10.4236/ajps.2022.136056.