The effects of copper nitrate on seedlings of Prosopis pubescens (Srew bean mesquite)
Copper smelting has increased heavy metal contamination in soils of the El Paso, TX-Juarez, Mexico area. Phytoremediation utilizes plants to remediate soils. Prosopis pubescens found in the Chihuahua desert was studied as a potential for phytoremediation in desert soils. Transmission electron microscopy was used to reveal ultrastructural changes within seedlings exposed to 0-600 ppm copper nitrate. Cell membrane breakage, plasmolysis of cotyledon parenchymal cells and chloroplast swelling were common changes observed. The copper concentrations in control roots, stems and cotyledons were 162.52, 72,55, and 64.12 mg/kg-1 respectively. In the 600 ppm copper nitrate seedlings the copper in the roots, stems and cotyledons were 16795.09, 2764.03 and 21284mg/ kg-1, respectively. Based on these results we believe that Prosopis pubescens may be used for phytoremediation of desert soils.