Callus Culture of common thyme (Thymus vulgaris L.)

The aim of the study was to investigate the influence of plant growth regulators on callus culture of common thyme (Thymus vulgaris L.) and the possibility of using such callus cultures to obtain rosmarinic acid. The explants used to initiate shoot culture were the seeds of common thyme. The seeds were individually placed into test tubes with MS culture media of macro- and micro-element content according to Murashige and Skoog (1962). For the purpose of initiation of cultures, leaves dissected along the vascular bundle were used. The leaves were placed on MS medium with the addition of BAP in combination with NAA in a concentration of 3 and 5 mg•dm-3. Propagation of callus cultures was conducted with the use of fragments of callus tissue placed on MS media supplemented with BAP used separately in a concentration of 3 mg•dm-3, and in combination with NAA (1, 2, 3 mg•dm-3) and 2,4-D in a concentration of 0.5, 1 or 1.5 mg•dm-3 respectively. In each stage of the experiment, explants placed on MS media without the addition of plant growth regulators were the control. It was found that initiation of common thyme cultures should be conducted on MS media without plant growth regulators. For the purpose of initiation of callus culture of common thyme, the optimal culture medium was MS with the addition of 3 mg•dm-3 BAP and NAA. Propagation of callus tissue of common thyme should be conducted on culture media supplemented with 3 mg•dm-3 BAP used in combination with 1 mg•dm-3 NAA. It was observed that the mass of the propagated callus tissue decreased with an increase of NAA content.