Physiological, biochemical and molecular characteristics of cryopreserved Hypericum perforatum L. shoot tips

Hypericum perforatum L. in vitro cultured shoot tips were characterised at the physiological, biochemical and molecular levels following recovery from cryogenic treatment using the plant vitrification solutions PVS2 and PVS3. This comparative study revealed an increase in recovery and regrowth of explants cryoprotected with PVS3. Among the physiological markers only lipid peroxidation in the regenerants treated with PVS2 significantly increased indicating membrane damage. Genotype-specific interactions were found in most characteristics studied, with some variation detected within control and cryopreserved samples. Analyses of metabolite biosynthesis and genetic stability showed no significant differences in hypericin content, RAPD and minisatellite amplification profiles between PVS2- and PVS3-treated explants. This study demonstrates and discusses the criteria selective for PVS3 to improve the cryopreservation of H. perforatum L.