Copper resistance of Calluna vulgaris originating from the pollution gradient of a Cu-Ni smelter, in southwest Finland

The copper (Cu) resistance of 1-year-old seedlings of heather (Calluna vulg aris) was tested in a greenhouse experiment. The plant material originated from seeds collected from three peatland sites located 1.2 km to the NW, an d 2.5 and 5.5 km to the NE of the Harjavalta Cu-nickel (Ni) smelter, SW Fin land. The plants were watered with a nutrient solution containing five diff erent levels of Cu (1, 10, 22, 46 and 100 mg l(-1)). Cu clearly decreased t he length growth of shoots, shoot and root biomass of C. vulgaris. More tha n 50% of the seedlings exposed to the highest Cu treatment died. C. vulgari s accumulated high amounts of Cu, the living old roots containing a maximum of 2200 mg kg(-1) Cu and the living stems 1300 mg kg(-1) Cu. Discolouring leaves contained higher Cu concentrations than green leaves. The results in dicate Cu accumulation in roots and root-to-shoot transport. Some differenc es were found between the responses of the three seed provenances, but none of the populations proved to be more resistant to Cu than the others in al l the measured responses. (C) 2000 Elsevier Science Ltd. All rights reserve d.