Plant response to heavy metals and sulphur dioxide

Abstract

The combined effects of sulphur dioxide and several heavy metals were studied on ion uptake through leaves, yield and foliar injury. Lactuca sativa L., Raphanus sativus oleifera L., Setaria italica L., Raphanus sativus redicula L. and Tagetes sp. plants were dusted with a mixture of CdO, PbO 2, CuO and MnO 2 once a week for four week weeks and, at the same time, exposed for the 28 days to 0·21 mg SO 2/m 3. The presence of sulphur dioxide did not influence uptake or translocation of heavy metals in any of the observed plant species. Manganese and lead uptake was less than that of other metals. Heavy metal treatment reduced yield in all plant species and was not influenced by SO 2 fumigation. Foliar injury, caused by heavy metals, was increased by sulphur dioxide in all tested plants. Uptake of heavy metals through leaves, yield reduction and foliar injury varied between plant species and was lowest in Lactuca sativa L.