Effect of copper on germination and seedling growth ofMinuartia,Silene, Alyssum andThlaspi

The influence of increasing copper concentrations on seed germination, seedling survival and radicle length ofMinuartia hirsuta, Silene compacta, Alyssum montanum andThlaspi ochroleucum was studied. Seed germination was highly affected by the higher Cu²⁺ concentrations (80 and 160 μM), while lower Cu²⁺ concentrations seemed to be necessary for seed germination, even for the plants originated from non-Cu²⁺-rich soils (i.e. A. montanum). Nevertheless, plants originated from Cu²⁺-rich soils (M. hirsuta, S. compacta) showed a higher demand of Cu²⁺ for rapid seed germination. Cu²⁺ at higher concentrations severely reduced growth rate of radicle, especially inA. montanum andT. ochroleucum. These data clearly indicate the reduced suitability of the above mentioned plant species for reclamation on Cu²⁺ soils. Lower Cu²⁺-concentrations had no influence on seedling survival inM. hirsuta andS. compacta, but a progressive reduction of a number of survived seedlings with increasing Cu²⁺ concentration was found, that was more pronounced inA. montanum andT. ochroleucum.