Copper bioavailability and phytotoxicity as assessed in situ for durum wheat cultivated in Cu-contaminated, vineyard soils

摘要

Copper bioavailability and phytotoxicity were assessed in situ for durum wheat cultivated in Cu- contaminated, vineyard soils that covered a wide range of pH (4.2-7.8) and total copper content (32- 1030mg(Cu)·kg<'-1>). Copper content in plants varied between 6 and 39 mg(Cu) ·kg<'-1> in shoots and between 11 and 705 mg(Cu)· kg<'-1> in roots. The highest Cu contents in plants were found in calcareous soils. Moreover, symptoms of Fe chlorosis were observed in calcareous soils, particularly at high Cu contents in soils and plants. In acidic soils, an increase in rhizosphere pH was found to be related to a decrease in Cu solubility. The results of this study suggested that Cu might be more bioavailable and even more phytotoxic in calcareous soils than in acidic soils. In addition, Cu phytotoxicity in calcareous soils seemed to be linked to Fe deficiency in durum wheat.