Interaction between a copper‐tolerant and a copper‐sensitive population of <i>Silene cucubalus</i>

Abstract

Interactions between copper‐tolerant and copper‐sensitive plants of Silene cucubalus (L.) Wib. were absent when grown in mixed culture in a nutrient solution with a normal Cu 2+ concentration (0.5 μ M ). When grown in mixed culture in a nutrient solution with 40.5 μ M CuSO 4 , however, the biomass production of the sensitive plants was less affected than when grown in monoculture. At 40.5 μ M Cu 2+ , in the presence of tolerant plants, the concentration of copper in both roots and shoots of sensitive plants was significantly diminished in comparison to a monoculture without tolerant plants. At the same time the copper concentration in the roots of the tolerant plants was higher in the presence of sensitive plants. The possibility of external detoxification of the copper by tolerant plants as a mechanism of heavy metal resistance is discussed.