Changes in the peroxidase spectrum induced by hormones and mutagens in Stachys sieboldii Miq. regenerants

Nodular segments of the stem and stolons of aseptic Stachys sieboldii (Miq. ) plants were cultured on Gamborg's B5 medium at a low (1-2 mg/l) or high ( 10 mg/l) concentration of cytokinins (6-BAP, kinetin) and produced many adv entitious buds and shoots without callus formation. Several plants were reg enerated from nodular segments incubated at various concentrations of 5-bro modeoxiuridine (5-BdU) for 3 weeks. All regenerants were morphologically no rmal. Peroxidase electrophoretic patterns were analyzed to determine whethe r somaclonal variation is associated with S. sieboldii micropropagation. Th e frequency of changed spectra was higher with the high 6-BAP concentration and with mutagenic treatment. Changed spectra were not detected in plants grown at a low cytokinin concentration, which can be used in S. sieboldii m icropropagation.