Absorção de cobre e potencial fitorremediador de Lantana Fucata (Verbenaceae)

Abstract

Phytoremediation is a technology that uses the ability of some plants to absorb, accumulate, metabolize, volatilize or stabilize contaminants present in the environment, where it is possible to mention metals. Copper (Cu) is an essential micronutrient for plant growth and development, although high levels of this metal can be extremely toxic to vegetation. The application of cupric fungicides for the diseases management in different kind crops, increases the Cu content in soils. Therefore, a study aimed to evaluate the tolerance, absorption and accumulation of Cu, considering a native plant of the Brazilian flora, Lantana fucata, in soil with high levels of metal. Experiments were conducted in a greenhouse with cycles of cultivation of 100 days. The experimental design was completely randomized, corresponding to Cu additions to the soil in the operations of 70, 140, 210, 280, 420, 630, 840 mg kg-1 of Cu and control (without addition). The post-cultivation derived parameters were: translocation factor (TF), bioconcentration factor (BC), metal extraction rate (MER), tolerance index (TI), height and dry mass. With the results it can be concluded that the Lantana fucata present good tolerance (IT> 100%), in all treatments, when compared with treatment 0 (IT = 100%). It was also efficient in the retention of this metal, mainly in the roots, obtaining FT <1 for both experiments and a variation of FBC 0.73 to 7.41 for experiment 1 and 0.18 to 4.68 for the experiment. experiment 2. TEM showed an average variation of 1.12% and 3.88% for experiment 1 and 2, respectively, being less effective in the treatment with the highest dose of Cu. Assuming, therefore, potential phytoremediation characteristics, through a phytostabilization mechanism, when the soil presents contamination of up to 140 mg kg-1.