Impacts of EDTA on uptake and accumulation of Cu2+ by spinach (Spinacia oleracea L.) seedlings replanted in hydroponic solutions

Abstract

The effects of EDTA on Cu²⁺ uptake by spinach (spinacia oleracea L) seedlings replanted in hydroponic solutions in a greenhouse were investigated. Four week old seedlings were exposed to various doses of Cu²⁺ (0, 5, 10, 15, and 20mg/L) and constant concentration of EDTA (10mM). During the exposure, the plant protected itself from the damage caused by Cu²⁺ uptake by using the antioxidant,(proline). The photosynthetic pigments (i.e. chlorophyll a, chlorophyll b and Carotenoid) gradually declined. In this study, dry weights and lengths of roots, shoots and contents of the photosynthetic pigments of both chelated and unchelated hydroponic treatments were investigated. Changes in photosynthetic pigments, root and shoot weights and lengths were significant (p < 0.05) with respect to addition of EDTA to different concentrations Cu²⁺ compared to unchelated treatments of same Cu²⁺ concentrations. Hence, chelation enhanced Cu²⁺ uptake with adverse effects on the plant.

Keywords: Photosynthetic, Chlorophyll, Chelation, Spinach, Hydroponic, Greenhouse