Abstract In vitro culture may provide a suitable environment for selection of heavy-metal tolerant plantlets. Such clones of woody plants could be valuable material applicable to soil remediation. In in vitro culture conditions shoots of Daphne jasminea Sibth. & Sm. and Daphne tangutica Maxim. (Thymelaeaceae) were grown on media supplemented with 0.1, 0.5 and 1.0 mM lead nitrate. Level of lead bioaccumulation, growth parameters, content of photosynthetic pigments, and mineral status of cultured shoots were investigated. D. jasminea has grown vigorously on Pb²⁺-containing media, with growth tolerance index reaching 73–89%, depending on concentration applied, and the highest growth value was obtained in the presence of 1.0 mM lead nitrate. In vitro propagation of D. tangutica shoots was slightly inhibited by lead ions, however the growth tolerance index has increased up to 152% on medium with 1.0 mM Pb(NO₃)₂. In both studied species the highest content of accumulated lead, as well as the value of bioconcentration factor, were found in shoots grown on 0.1 mM lead nitrate. D. tangutica accumulated over two times as much lead in comparison with D. jasminea. Chlorophyll content in D. jasminea was not affected by applied lead nitrate doses, while in D. tangutica stimulation of chlorophyll, as well as carotenoid, synthesis occurred. In tested concentrations lead nitrate had no toxic effect on the level of shoot nutrition. Detected levels of essential and trace elements were still high enough to maintain undisturbed growth and development of cultured shoots. This is first report confirming the suitability of in vitro selection for obtaining of vigorous, proliferative, tolerant to elevated lead concentration shoots of ornamental Daphne species.

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