الفهرس 
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Abstract
This study aimed to evaluate the efficiency of sunflower and indian mustard plants in phytoremediation of metal contaminated soils. Moreover, investigating the effect of synthetic and organic chelators on bioavailability and mobility of heavy metals on one hand, and on leaching behaviors of heavy metals under these chelators on the other hand. •Methods & Results : Three pot experiments were conducted in a wired greenhouse at Sakha Agricultural Research Station, Kafr El-Sheikh Governorate. The experiments aimed to investigate the phytoextraction efficiency of Cu, Zn and Pb from contaminated soils using sunflower (Sakha 53) and indian mustard var. Dama (introduced from Canada 1980) under Chelators (EDTA, citric acid (CA) and humic acid (HA)) addition during summer season of (2013) and winter season of (2013-2014). Moreover, investigating the leaching behaviors of studied metals under these chelators addition. The overall results demonstrate that EDTA had the highest efficacy on enhancing Cu and Zn absorption by sunflower and indian mustard plants. Application of CA also increased Cu and Zn absorption by both plant species, while HA was only efficient to increase Zn absorption by both plant species. Applying EDTA induced toxicity due to accumulation of Cu and Zn in the plant organs, so reduced the dry matter of these organs, besides, its increment effect of groundwater contamination risk via metal leaching. •Conclusion : -It can be concluded that sunflower was more efficient than indian mustard in the phytoextraction of Cu and Zn from polluted soils. -Using CA for the phytoremediation of Cu as well as CA and HA for the phytoremediation of Zn is favorable than EDTA despite the high efficiency of EDTA, due to either its harmful effect of high rates on plant growth or its increment effect of groundwater contamination risk via metal leaching. -EDTA can persist in soil for long periods of time because of its low biodegradability compared to CA and HA. Consequently, EDTA can enhance the phytoremediation of metals from contaminated soil in two successive seasons after addition once in the first season. However, its prolonged presence in the soil, and its non-selective nature, dramatically increase the leaching risk of heavy metals.