Lead Uptake by Roots of Four Turfgrass Species in Hydroponic Cultures

Abstract

Turfgrass, which is widely grown and produces a large amount of biomass, could act as a sink for industrial pollutants in urban and suburban regions. Little research has been conducted regarding heavy metal uptake by turfgrasses. The objective of this study was to evaluate root uptake of lead (Pb) in four turfgrass species. Grasses were grown hydroponically in solutions containing from 0 to 450 mg·L-1 Pb, at either pH 4.5 or 5.5, for 4 or 8 days. A significant quadratic relation existed between Pb accumulation in roots and solution Pb concentration within the tested range. The maximum Pb accumulation in roots of the four species was in the range of 20 mg·g-1 dry root weight. Tall fescue (Festuca arundinacea Schreb.) and Spartina patens survived at 450 mg·L-1 Pb solution without showing obvious damage while centipedegrass [Eremochloa ophiuroides (Munro) Hack.] and buffalograss [Buchlöe dactyloides (Nutt.) Engelm.] deteriorated or died at this concentration. This study showed that turfgrass plants can absorb heavy metals efficiently and tolerate high Pb concentration in hydroponic solutions and thus may have a potential use in environmental remediation as a biological extractor of lead.