engleski

Propagation and antioxidative enzymes of Campanula velebitica Borbás grown in vitro

Background and purpose: Micropropagation possibility for Campanula velebitica Borbás (Campanulaceae), a rare Croatian endemic plant was studied. Additionally, the activity of several antioxidative enzymes, as biomarkers of stress conditions, was investigated in plants grown in vitro. Materials and methods: Shoots from aseptically germinated seeds, collected from natural habitat, were used for culture initiation. Multiplication rate of shoots was monitored after six weeks on half-strength Murashige and Skoog (MS) medium supplemented with 0, 0.2, 0.5 and 1.0 mM 6-benzylaminopurine (BA). Rooting was induced on half-strength MS medium supplemented with 2.9 or 5.7 mM indole-3-acetic acid (IAA) ; or 2.5 or 4.9 mM indole-3-butyric acid (IBA). Activity of ascorbat (APX) and guaiacol (GPOD) peroxidases as well as catalase (CAT) was determined in shoot extracts spectrophotometrically and in gel. Results and conclusions: The highest multiplication rate, 7.7 shoots per explant, was achieved in the 3rd subculture on the medium containing 1.0 mMBA. Very good rooting (>90%) of excised shootswas achieved on media containing either indole-3-butyric acid (IBA) or indole 3-acetic acid (IAA). On the medium containing 4.9 mM IBA flowering was observed. Activities of APX and GPOD were significantly increased on media containing lower concentrations of BA (0.2 and 0.5 mM).Native PAGE analysis revealed one CAT, three GPOD and two APX isoenzymes. We conclude that C. velebitica is easily propagated in in vitro conditions, without substantial stress response. With further studies of plantlet acclimation, this endemic plant species could be efficiently preserved through culture in vitro.

Campanula velebitica; endemic plant; micropropagation; antioxidative enzymes

nije evidentirano