In vitro PROPAGATION OF Arnica montana L.: AN ENDANGERED HERBAL SPECIES OF GREAT IMPORTANCE TO MEDICINE

Arnica montana L., a valuable medicinal plant, has been used in the pharmaceutical and cosmetic industry for many years. Traditional methods of reproduction of this protected species are hardly efficient; hence, the method of in vitro culture provides the possibility of increasing the multiplication coefficient, which in turn would facilitate introduction of arnica into crop production. The aim of the study was to examine the effect of cytokinins and their concentration on multiplication of shoots and the effect of different concentrations of auxin on rooting of multiplied shoots of Arnica montana. The plants of mountain arnica were propagated from shoot tips placed on the MS agar (0.7%) medium supplemented with NAA (0.1 mgm.l(-1)). One of the four cytokinins, i.e. BAP, KIN, 2iP and Z, was applied at the concentrations of 0.5, 1.0, 1.5 and 2.0 mgm.l(-1). After 5 weeks of the in vitro culture, the shoots obtained were transferred to the MS agar medium supplemented with 0, 0.05, 0.1 and 0.2 mgm.l(-1) NAA for rooting. The greatest number of the explants regenerating shoots and the shoots number were found in the MS medium supplemented with 0.5 mgm.l(-1) BAP. KIN at the concentrations of 1.5 and 2.0 mgm.l(-1) exerted the most substantial impact on the shoot length. No change in shoot length and weight was found in the case of Z, and a bigger number of shoots was obtained at its concentrations ranging 1.0 to 2.0 mgm.l(-1). The shoots of the mountain arnica were characterised by high rhizogenic capacity. The biggest numbers of rooted shoots were found in the medium containing 0.1 mgm.l(-1) NAA. Plants with the greatest number and weight of shoots were obtained in the same medium, while the longest roots were found at 0.05 mgm.l(-1) NAA.