Growth, distribution and content of copper and zinc in Jatropha curcas L. plants

Abstract

Researches concerning the extraction of heavy metals by Jatropha curcas L. plants are still preliminary and incomplete. With the prospect of this plant to be used in phytoremediation of polluted soils, this study aimed to evaluate the effect of copper and zinc in the initial development of Jatropha curcas L. and accumulation and distribution of these elements in this plant. Two experiments were carried out in design completely randomized with three replications; the first one with five copper (0; 25; 50; 75; 100 mg dm^-3) and the second with four zinc (0; 50; 100; 150 mg dm^-3) treatments. At 50; 70; 90 and 110 DAS, were evaluated: plant height, stem diameter and leaf area. At the end of the experiment the plants were harvested and assessed the levels of copper and zinc in plant tissues. Soil samples were collected from each pot and subjected to chemical analysis. The Jatropha curcas L plants, during the experimental period are tolerant to the treatments, however, copper and zinc levels in soil above 75 and 50 mg dm^-3, respectively, affect their growth. The copper and zinc concentrations in the plants were ranked in the following order, respectively: leaf > roots > stem; stem > leaf > root. Zinc translocation was higher than copper in the plants.