EFFECT OF COPPER ON GERMINATION AND SEEDLING GROWTH OF MINUARTIA, SILENE, ALYSSUM AND THLASPI

The influence of increasing copper concentrations on seed germination, seedling survival and radicle length of Minuartia hirsuta, Silene com pacta, Alyssum montanum and Thlaspi ochroleucum was studied. Seed germ ination was highly affected by the higher CU2+ concentrations (80 and 160 mu M), while lower Cu2+ concentrations seemed to be necessary for seed germination, even for the plants originated from non-Cu2+-rich so ils (i.e. A. montanum). Nevertheless, plants originated from Cu2+-rich soils (M. hirsuta, S. compacta) showed a higher demand of Cu2+ for ra pid seed germination. Cu2+ at higher concentrations severely reduced g rowth rate of radicle, especially in A. montanum and T. ochroleucum. T hese data clearly indicate the reduced suitability of the above mentio ned plant species for reclamation on Cu2+ soils. Lower Cu2+-concentrat ions had no influence on seedling survival in M. hirsuta and S. compac ta, but a progressive reduction of a number of survived seedlings with increasing Cu2+ concentration was found, that was more pronounced in A. montanum and T. ochroleucum.