CADMIUM AND ZINC IN SOYBEAN CROP, GREAT CHALLENGERS IN THE METABOLISM OF OXIDATIVE STRESS

GALLARDO, LV, MOLINA AS, ZIRULNIK F AND PÉREZ CHACA, MV

BIOCELL

Biocell

Lugar: Mendoza; Año: 2019 vol. 43 p. 81 - 81

1667-5746

There are serious problems associated with the contamination of soils by heavy metals, generating competition between polluting metals and essential metals. The Zn is an essential element for both, plants and animals, however in excess causes alterations in important processes for the development of the organism. Cadmium (Cd) is a heavy metal without biological functions; even in low concentrations it causes damage at the cellular and molecular level. By having the same charge as an essential metal, the plant absorbs by the same transporters (IRT1-ZIP) Cd and Zn, interfering in the entry, transport and use of microelement. The similarity between both ions lead to comparable toxicity symptoms, such as the reduction of biomass, elongation decrease and darkening of the main roots, chlorosis and leaf necrosis, and also causing changes in oxidative stress parameters. The objective of this study was to establish the mechanisms of tolerance in the presence of cadmium and zinc, evaluating morphological and biochemical changes in soybean plants. In our study model, leaves and roots of Glycine max were used. After 10 days of development and adaptation to hydroponic conditions in Hoagland nutrient solution, they were exposed to contamination with Cd and Zn, for 6 days. The following work concentrations of ZnCl2 (0; 1.2 and 6.1mM) were selected from a concentration curve, while the concentration of CdCl2 was constant (40 μM). Dry weight, root and stem length and leaf area were determined; MDA was measured as oxidative stress parameter and catalase (CAT) as antioxidant enzyme. The results of the morphophysiological parameters showed a significant decrease, both in root and stem length, in all the treatments compared to the control (p