Plant uptake and phytotoxicity of decabromodiphenyl ether (BDE-209) in ryegrass (Lolium perenne L)

Abstract

The plant uptake and phytotoxicity of decabromodiphenyl ether (BDE-209) in ryegrass (Lolium perenne L) seedlings were investigated. Results showed that ryegrass could take up BDE-209 from the contaminated soils and most of the BDE-209 in plants is located in roots, indicating that BDE-209 has low root-to-shoot translocation. Except for about 35% inhibition of root growth and about 30% decrease of the chlorophyll b and carotenoid contents of leaves, no visual toxicity symptoms were observed in seedlings grown even at a high concentration of 100 mg kg⁻¹. BDE-209 exposure significantly induced the generation of the superoxide radical (O₂˙⁻) and malondialdehyde (MDA) in ryegrass leaves. With the increase of BDE-209 concentration, the activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and glutathione-S-transferase (GST) were significantly changed, and the ratio of reduced glutathione to oxidized glutathione (GSH/GSSG) was also significantly reduced. Results suggested that BDE-209 exposure could cause oxidative stress and damage, which may play an important role in the phytotoxicity of BDE-209 in ryegrass seedlings.