Estudos do cromo trivalente sobre os aspectos fisiológicos, anatômicos e genéticos em plantas

Abstract

Environmental contamination by heavy metals is a global concern, since the main source of these pollutants are industrial and domestic effluents. Chromium is a heavy metal found more abundantly in the water resources of the Holy Spirit according to a diversity of industrial activities. In this context, we evaluated the effects of decreasing concentrations of trivalent chromium in anatomy and physiology in seedlings of Inga vera Willd. (Fabaceae) and its effect on cells in the aspect of toxicity and mutagenicity in meristematic cells of Allium cepa L. (Liliaceae) roots. Roots from bulbs of A. cepa were kept in solutions of trivalent chromium at different concentrations, 0.5000 mg / L, 0.0500 mg / L, 0.0250 mg / L, 0.0125 mg / L, 0.0062 mg / L and 0 , 00 mg / L for 24, 48 and 72 hours for evaluation of cytotoxicity, genotoxicity and mutagenicity.Plants at Inga vera seedlings were exposed to pollutant concentrations of 0.5000 mg / L, 0.0500 mg / L, 0.0250 mg / L, 0.0125 mg / L and 0.00 mg / L for 60 and 120 days. The roots and leaves were collected for physiological evaluations, where we measured the growth and biomass. In leaves were also mediated photosynthetic pigments. Cuts were made with the different anatomical parts of plants to compare the specimens exposed to chromium for those who grew up in the absence of such pollutant. Information obtained in this study should alert environmental inspection agencies on the impact generated by trivalent chromium, pollution potential of effluents, for the prevention of public health, since there is the possibility of consumption of aquatic animals and contaminated agricultural products. Compared to the cytotoxicity was possible to note that the highest concentrations in cell division decreased as exposure time increases. The highest concentrations tested showed high genotoxic potential, however with increasing exposure time the situation was normalized. For mutagenicity observed statistically higher proportional to the concentration of the metal chromium. These data indicate an acute effect on genotoxicity and mutagenicity caused by this metal in A. cepa. The data analysis of growth in plants of Inga vera, showed no significant difference between treatments. In the analysis of photosynthetic pigments was observed that individuals exposed to different concentrations showed similar levels of pigments. Leaves and roots of plants and are not exposed to chromium showed no change in their organizations. The results indicate that I. vera is a species resistant to the concentrations of chromium analyzed under the conditions of this experiment