Micropropagation of Iranian native oregano (Origanum vulgare L.) using growth regulators

Wild oregano (Origanum vulgare L.) belonging to the Labiate family is one of the most important medicinal plants in Iran and the world. It is widely used in the medicinal, food, and health industries. The present study aimed to investigate the in vitro culture of Iranian native oregano. Two experiments were designed to investigate the proliferation and rooting of this species. In the proliferation stage, benzyl adenine (BA) was used at four levels (0, 0.5, 1, and 1.5 mg/l) along with 0.25 mg/l indole butyric acid (IBA). For the rooting stage, IBA at four levels (0, 0.5, 1, and 1.5 mg/l) in combination with 0.5 mg/l naphthalene acetic acid (NAA) was used. The results showed that BA caused a significant effect on the leaf number, the number of shoots, the shoot length, chlorophyll index, and the leaf dry weight. The highest number of leaves and shoots and the highest value of chlorophyll index were seen in the medium containing 1.5 mg/l. The longest shoot and the highest leaf dry weight were related to 1 mg/l BA. In addition, the results related to the rooting stage showed that the root length, root diameter, and total dry weight of plantlets were significantly affected by IBA, while the number of roots was not influenced by IBA. The highest root diameter and total dry weight of plantlets were obtained in the medium containing 0.5 mg/l IBA, and the maximum root length was obtained in the MS medium without IBA.