Ethylenediaminetetraacetic Acid (EDTA) Mitigates the Toxic Effect of Excessive Copper Concentrations on Growth, Gaseous Exchange and Chloroplast Ultrastructure of Corchorus capsularis L. and Improves Copper Accumulation Capabilities

Copper (Cu) is an important micronutrient for a plant's normal growth and development. However, excess amount of Cu in the soil causes many severe problems in plants-which ultimately affect crop productivity and yield. Moreover, excess of Cu contents causes oxidative damage in the plant tissues by generating excess of reactive oxygen species (ROS). The present experiment was designed to investigate the phytoextraction potential of Cu, morpho-physiological features and biochemical reaction of jute (Corchorus capsularisL.) seedlings using ethylenediaminetetraacetic acid (EDTA) of 3 mM under different Cu levels (0 (control), 50 and 100 mu M) in a hydroponic nutrient solution (Hoagland). Our results showed that elevated Cu rates (50 and 100 mu M) in the nutrient solution significantly reduced plant height, fresh and dry biomass, total chlorophyll content and gaseous exchange attributes inC. capsularisseedlings. As the concentration of Cu in the medium increased (50 and 100 mu M), the level of malondialdehyde (MDA) and oxidative stress inC. capsularisseedlings also increased, which could have been controlled by antioxidant activity in particular plant cells. In addition, rising Cu concentration in the nutrient solution also increased Cu uptake and accumulation in roots and leaves as well as affected the ultrastructure of chloroplast ofC. capsularisseedlings. The addition of EDTA to the nutrient solution significantly alleviated Cu toxicity inC. capsularisseedlings, showing a significantly increase in plant growth and biomass. MDA contents was not significantly increased in EDTA-induced plants, suggesting that this treatment was helpful in capturing ROS and thereby reducing ROS in inC. capsularisseedlings. EDTA modification with Cu, although the bioaccumulation factor in roots and leaves and translocation factor for the leaves ofC. capsularisseedlings has significantly increased. These results indicate thatC. capsularishas considerable potential to cope with Cu stress and is capable of removing a large quantity of Cu from the Cu-contaminated soil while using EDTA is a useful strategy to increase plant growth and biomass with Cu absorption capabilities.