Umwelt- und analytische Toxikologie

The Effect of Varying Soil Organic Levels on Phytoextraction of Cu and Zn uptake, enhanced by chelator EDTA, DTPA, EDDS and Citric Acid, in Sunflower (Helianthus annuus), Chinese Cabbage (Brassica campestris), Cattail (Typha latifolia), and Reed (Phragmites communis)

Abstract

T.Y. Yeh, C.F. Lin, C.C. Chuang and C.T. Pan

Focusing on the influence of organic soil contents on the Phytoextraction of Cu and Zn, assisted by chelators EDTA, DTPA, EDDS, and citric acid, in Sunflower (Helianthus annuus), Chinese Cabbage (Brassica campestris), Cattail (Typha latifolia), and Reed (Phragmites communis), this study demonstrates prominent Cu and Zn uptake enhancement. Soil organic concentration has been shown to be a critical factor in metal uptake and bioavailability in plants. Organic content has less soil nutrients, and less negatively charged functional groups, such as carboxical, phenolical and hydroxyl groups. This allows adsorption of negative free metal cations, and reduces metal mobility. Regardless of various soil organic contents, this study ranks Cattail, Reed, Sunflower, and Chinese Cabbage, in descending order of propagation efficacy. The mechanism of metal is apoplastic transportation. In plant cells, the apoplast is the free diffusional space outside the plasma membrane. It contains high concentrations of carboxylic groups which act as effective cation exchangers. The negatively charged chelator complexes are prevented from being bound to the cell walls of the roots, and allow complexes to enter into the cells. Metal chelator complexes are subsequently translocated to the aerial part of plant via the passive apoplastic pathway. Metal is seen to accumulate in the roots, stems, and leaves, in descending order of concentration; a result similar to most other research conclusions.