Multiplication of lavender (L. angustifolia) and lavandin (Lavandula x intermedia) in explant culture

Lavender plants are preferably propagated vegetatively. The aim of the work was to propose the composition of nutrient media for in vitro multiplication of plants of Lavandula angustifolia (var. Krajová and Beta) and Lavandula x intermedia (var. Budrovka and Grosso). Explant cultures were initiated from apical or nodal segments. Apical segments were more suitable and regenerated the highest number of shoots in MS medium supplemented with 1 mg/L BAP with or without 0.1 mg/L IAA in all used varieties. Nodal segments are suitable for var. Budrovka, where the number of shoots was not statistically different between the apical or nodal segments and among the media tested. Shoot multiplication of L. angustifolia varieties was the most effective in the MS media with 0.5 or 1 mg/L BAP. For variety Grosso, the optimal medium was MS with 1 mg/L BAP, while var. Budrovka regenerated a similar number of shoots in all media supplemented with 0.5 or 1 mg/L BAP with or without 0.1 mg/L IAA. All genotypes rooted with the highest frequency on growth regulator-free medium with a half dose of MS salts. After transplanting into the soil and ex vitro acclimatization, plantlets survivability after 10 weeks was 78.9 – 87.7%, except for var. Beta with a lower survivability of 50%. The proposed procedures enable a rapid plant multiplication of varieties Budrovka, Grosso and Krajová. With the Beta variety, it is advisable to continue working on the optimization of nutrient media to verify whether the procedures can be further optimized.