Pawełczak A., Osińska E., Geszprych A., Węglarz Z.

One of the essential problems in the cultivation of Hypericum perforatum is to obtain healthy and genetically uniform plant material for establishing of plantations. The aim of the study was to compare developmental and chemical characteristics of H. perforatum plants propagated generatively and by micropropagation. The experimental plant material were cv. ‘Topas’ and two populations (No. 25 and 31) selected in the Department of Vegetable and Medicinal Plants. Micropropagation was carried out using initial shoot explants taken from mature plants growing in the field. Multiple shoot regeneration was obtained on LS (Linsmaier & Skoog) medium supplemented with 3 mg L-1 kinetin, 0.3 mg L-1 indole 3-acetic acid (IAA) and 80 mg L-1 adenine sulfate. Rooting of regenerated shoots was induced on 1 LS (modified LS, containing half of the original concentration of macronutrients) with 0.5 mg L-1 IAA. Both media were supplemented with 20 g L-1 sucrose and 6.5 g L-1 agar. All cultures were incubated at 24°C and 16-hour day. Rooted plants were adapted to ex vitro conditions. The plant material obtained in vitro was compared with that obtained from the seeds sown in the greenhouse. In vitro regenerated and generatively propagated plants did not differ in respect of plant habit. The propagation method did not affect the content of hypericins, polyphenolic acids and flavonoids in the air-dry herb harvested at the full blooming stage. The herb of cv. ‘Topas’ was characterised by the highest content of hypericins and the lowest content of polyphenolic acids.

Key words: micropropagation, flavonoids, hypericin, polyphenolic acids