Propagation of Clematis ‘Warszawska Nike’ in In Vitro Cultures

Abstract

A micropropagation protocol for growing Clematis ‘Warszawska Nike’ was developed. The MS medium supplemented with 1 mg∙dm−3 BAP showed good results in the case of microshoot initiation (80%). The addition of BAP to the medium at higher concentrations resulted in the formation of a large amount of callus tissue at the base of the explant. Of the explants growing on the medium with the lowest cytokinin concentration, 8% flowered. Very quickly, after just 14 days, the explants began to die: some of the leaves that developed in in vitro cultures began to turn yellow and wither. The propagation of shoots was performed in two steps. In the first step, cytokinin BAP and Kin in various concentrations (0.5–2 mg∙dm−3) were added to the MS medium. In the second step, MS medium with the combinations of BAP (0.5 and 1 mg∙dm−3) with IAA or GA3 (1 and 2 mg∙dm−3) was used. The MS medium with 0.5 mg∙dm−3 BAP and 2 mg∙dm−3 GA3 was the best medium for the multiplication stage of clematis. Plants growing on this medium had the largest number of leaves, shoots, and internodes, and were also heavier compared to plants propagated on other media. The proliferated clematis explants were rooted on MS medium with the addition of IAA or IBA in different concentrations (0.5 to 4 mg∙dm−3). Of the concentrations tested, 0.5 mg∙dm−3 IAA was the most effective one for in vitro root induction. The highest percentage of acclimatized plants (75%) was observed when the shoots were rooted on MS medium with 0.5 mg∙dm−3 IAA.