Phytotoxic effect of some metal ions on selected rapeseed cultivars registered in Slovakia

The aim of this study was to investigate the phytotoxic effects of seven metal ions (Cd(II), Cr(VI), Cu(II), Hg(II), Ni(II), Pb(II) and Zn(II)) on length of roots of five rapeseed (Brassica napus L. subsp. napus) cultivars registered in Slovakia (Atlantic, Baldur, Californium, Oponent and Verona). The phytotoxic effect of metals was evaluated using IC50 values. The studied metal ions inhibited germination and root growth of rapeseed seedlings. In general, the toxicity of metal ions decreased in the following order Cu > Cr >Hg > Cd > Pb > Ni > Zn. Atlantic, Baldur and Californium were more sensitive to Cd than to Ni, for Oponent and Verona higher toxicity exhibited Ni. From the studied rapeseed cultivars Atlantic and Californium were found to be most sensitive to tested metals. On the other hand, high tolerance to metal treatment was determined for Baldur. Czech cultivar Opponent showed high tolerance to Cd, Cr, Cu and Pb, but it was sensitive to Hg and Ni. The above-mentioned results confirmed differences in the metal tolerance of tested rapeseed cultivars.