Lead Tolerance and Enrichment Characteristics of Several Ornamentals Under Hydroponic Culture

摘要

The growth response, tolerance, and enrichment characteristics of six ornamental species,Chlorophytum comosum,Calendula officinalis,Iris lacteal,Belamcanda chinensis,Saponaria officinalis, andPolygonum lapathifoliumwere studied under hydroponic culture with lead (Pb) concentrations ranging from 0 to 1000 mg/L. The results showed that the growth of the tested ornamental species under Pb stress was inhibited.Belamcanda chinensispresented the largest tolerance index (0.75), andCalendula officinalishad the highest toxicity threshold (500 mg/L) under Pb stress. The highest Pb contents in the shoots were detected inIris lactealandBelamcanda chinensis. The enrichment coefficients in the shoots ofIris lactealandBelamcanda chinensiswere significantly higher than those in the other ornamental species. In conclusion,Iris lactealandBelamcanda chinensisare the most tolerant and have the greatest Pb enrichment and translocation abilities under Pb stress, and thus, they have a strong potential to restore Pb-contaminated water bodies and soils.