Biochar como atenuador em plantas jovens de Ucuúba (Virola surinamensis ((Rol. ex Rottb.) Warb.) submetidas a solos contaminado por cádmio na Amazônia: sistema antioxidante e indicadores de estresse

Abstract

Heavy metals, such as cadmium (Cd), impact plants and human health due to their high toxicity and mobility. Cd causes oxidative stress, affecting plant survival. Therefore, biochar (BC), obtained from agricultural waste such as açaí seeds, can reduce this contamination. Ucuúba can tolerate heavy metals, being useful in phytoremediation. The objective of this study was to analyze the effect of biochar on the oxidizing system in Ucuúba seedlings subjected to different doses of cadmium. The experiment was conducted in a greenhouse belonging to the Institute of Agricultural Sciences, located at the Federal Rural University of the Amazon, using Virola surinamensis seedlings in soils contaminated with different doses of Cd (0, 10, 20 and 30 mg L-1) and different proportions of biochar (0%, 5% and 10%). Biochar was obtained from açaí seeds. A randomized block design (RBD) was used in a 4x3 factorial scheme with four replicates, totaling 48 experimental units. The enzymatic (SOD, CAT, GPOD and APX) and non-enzymatic (MDA, TBARS and PROLINE) variables were determined and subjected to analysis of variance by the F test, and when significant, the Tukey test was applied at a 5% probability level. The results showed that from 10 mg L⁻¹ of cadmium, oxidative stress was observed in the plant, with enzymatic alterations and increased lipid peroxidation. Biochar, especially at a proportion of 5%, reduced the damage, aiding in soil remediation.