Chelate-assisted phytoextraction: Effect of EDTA and EDDS on copper uptake by Brassica napus L.

Abstract

Chelate-assisted phytoextraction is proposed as an effective approach for the removal of heavy metals from contaminated soil through the use of high biomass plants. The aim of the present study was to compare the efficiency of the two chelators: EDTA and biodegradable EDDS in enhancing Cu uptake and translocation by Brassica napus L. grown on moderately contaminated soil and treated with increasing concentrations of EDTA or EDDS. Increasing amounts of EDDS caused serious growth suppression of B. napus and an increase in shoot metal concentrations. Growth suppression limited the actual amount of phytoextracted Cu at high concentrations of EDDS. The maximum amount of extracted Cu was achieved by the application of 8.0 and 4.0+4.0 mmol kg-1 EDDS. The shoot Cu concentrations after EDTA application were much lower than with EDDS at the same doses. According to these experiments, EDTA does not appear to be an efficient amendment if Cu phytoextraction with B. napus is considered but EDDS is.

Smatra se da upotreba biljaka sa visokom biomasom za fitoekstrakciju potpomognutu helatorima može predstavljati efikasan način za uklanjanje teških metala iz kontaminiranog zemljišta. Cilj ovog istraživanja je bio da se uporedi efikasnost dva helatora: EDTA i biodegradabilnog EDDS u povećanju vezivanja i translokacije bakra kod vrste Brassica napus L. gajene na umereno zagađenom zemljištu. Rastuće koncentracije EDDS su izazvale i povećano vezivanja bakra i izražen zastoj u porastu nadzemnog dela biljke B. napus L. Količina fitoekstrahovanog bakra pri visokim koncentracijama EDDS je bila ograničena zastojem u porastu nadzemnog dela biljke. Najveća količina fitoekstrahovanog bakra je postignuta sa primenom 8,0 i 4,0+4,0 mmol kg-1 EDDS. Koncentracija bakra u nadzemnom delu nakon primene EDTA je bila mnogo niža nego prilikom primene EDDS u istim koncetracijama. Na osnovu rezultata dobijenih u ovom eksperimentu, utvrđeno je da, za razliku od EDDS EDTA nije dovoljno efikasan helator za fitoekstrakciju bakra pomoću B. napus L.