Improvement of germination rate and in vitro multiplication of Lavandula angustifolia

Abstract

Lavender is well-known for its essential oils, which are in high demand and have a very important economic interest, particularly for the pharmaceutical and cosmetic industries. This work had been done to study seed germination and in vitro culture of Lavandula angustifolia. The seeds of L. angustifolia had undergone a vernalization followed by two treatments (physical and chemical), in order to increase the percentage of germination. Seeds were introduced into tubes containing the culture medium Murashige et Skoog (MS). Untreated seeds were germinated in the same medium supplemented with gibberellic acid at different concentrations. The kinetics, the speed, and the final germination rate were retained in order to evaluate the response of seeds. The micropropagation of L. angustifolia was performed on MS medium supplemented with different concentrations of 6-Benzylaminopurine (Treatment I) and 6-Benzylaminopurine in combination with Naphthalene Acetic Acid (Treatment II). Multiplication rate, shoots number, nodes number, leaves number, and stem length were determined. Lavandula angustifolia seeds revealed very low germination percentages for all the treatments used. However, those treated with sand (physical treatment) showed the highest percentage of germination (22%) followed by sulfuric acid treatment with a percentage of 14%. Results showed that the 11.11 μM concentration of 6-Benzylaminopurine favored the maximum reactivity of the explants. The combination between 6-Benzylaminopurine and Naphthalene Acetic Acid showed that MS supplemented with 8.88 μM 6-Benzylaminopurine and 2.68 μM Naphthalene Acetic Acid was the most effective in the development of vitroplants.