Micropropagation of Lavandula angustifolia Mill. 'Record' and 'Belyanka'

Lavender (Lavandula angustifolia Mill.) is one of the most economically valuable aromatic, medicinal and ornamental plants. Traditional techniques for lavender propagation are not efficient enough to produce virus-free and genetically uniform plant material. The aim of this study was to investigate the features of in vitro establishment and multiplication of L. angustifolia cultivar 'Record' and hybrid form Nº 83-91 ('Belyanka') for further genebank in vitro establishment. Mother plants were tested for viral infection by RT-PCR. Meristems 0.5-0.7 mm long were isolated from the tips of apical and axillary buds. For initiation the explants development were placed on MS culture medium with growth regulators. For viral infection elimination 5-20 mg L^-1 ribavirin was used. Meristem development started after 6 days of the culture. The best medium was MS with lower concentrations of plant growth regulators. Multiple shoots developed on MS medium with 0.3 mg L^-1 kinetin, 0.025 mg L^-1 NAA and 0.25 mg L^-1 GA₃. After 1.5-2 months the multiplication rate was 18.5 shoots per explant for the hybrid Nº 83-91 and 9.8 shoots for 'Record', and the length of the shoots was 3.8 and 3.12 cm, respectively. During micropropagation spontaneous rooting of shoots was observed.