Effect of plant species and benomyl on lead concentration and removal from lead-enriched soil

Abstract

Some agricultural soils in North America are lead (Pb)-enriched as a result of the application of lead arsenate (PbHAsO4) insecticide. A controlled-environment experiment was conducted with Pb-enriched Canning soil series in Nova Scotia, Canada, to evaluate the remediation potential of 10 plant species in combination with the fungicide benomyl applied as a soil drench to suppress mycorrhizae. Overall, the highest biomass was provided by yellow poppy followed by Indian mustard and thorn apple. The application of benomyl increased Pb concentration in thorn apple tissue but not in the other crops. The phytoremediation potential (Pb removal with the harvested biomass) was higher with clary sage, alyssum, garden sage, and Indian mustard with benomyl treatments and lower in the Swiss chard, thorn apple without benomyl, and in the geranium with benomyl treatments. The results suggest that some plants can be used for phytoremediation of mildly Pb-contaminated soils.