The influence of flavonoid amendment on the absorption of cadmium in Avicennia marina roots

Flavonoid is a key factor for the tolerance to cadmium in plants. Concentration-dependent kinetics experiment was conducted to investigate the influence of flavonoid amendment on the Cd2+ uptake in Avicennia marina (Forsk) Vierh. roots. We found that compared with the control, saturation concentration and maximal absorption rate of Cd was higher under flavonoid amendment (p < 0.05). When roots were exposed to ion transport inhibitor (LaCI3), flavonoid amendment also facilitated Cd transport in roots. Flavonoids had no influence on Cd2+ uptake in root cell walls. In conclusion, flavonoids enhance the tolerance to Cd and have a significant stimulative effect on symplasm transport of Cd in A. marina roots. Ca2+-chanriel was not the unique means of symplasm transport for Cd2+ absorption. (C) 2015 Elsevier Inc. All rights reserved.