Analysis on the Tolerance of Four Ecotype Plants Against Copper Stress in Soil

Abstract

To screen copper tolerant species, Four ecotype plants, Catalpabungei C. A. Mey, Catalpa ovata G. Don, tall fescue (Festuca arundinacea), and Sedum lineare Thunb, were planted in soil contaminated by Cu in greenhouse to reveal their characteristics of survival, growth and morphology, as well as copper uptake, accumulation and translocation in plants. The survival rate(S) of Catalpabungei C. A. Mey under Cu stress was high, while that of Catalpa ovata G. Don was just the opposite. With the increasing of Cu concentrations in soil, tree height(H) increment percents of both Catalpabungei C. A. Mey and Catalpa ovata G. Don declined significantly(significant level, α=0.05), but for stem bases(D) there were not obvious differences. The translocation factors (TF) and bioconcentration factors(BCF) of Catalpabungei C. A. Mey and Catalpa ovata G. Don were both lower than 0.5. The Cu content in roots of Catalpabungei C. A. Mey was significantly positively correlated with that in soil(r = 0.98; P < 0.05). Tolerance index (TI) of tall fescue and Sedum lineare Thunb were low. The concentrations of Cu in tall fescue and Sedum lineare Thunb both had significantly positive correlation with those in soils. The results suggested that Catalpabungei C. A. Mey, tall fescue, and Sedum lineare Thunb were tolerant to Cu stress in soil to some extent, and were of application potential as pioneer species for ecological restoration in areas suffering Cu pollution.