Repartição de nutrientes e selênio na castanheira-do-Brasil (Bertholletia excelsa)

Abstract

Brazil nut (Bertholletia excelsa) is characterized as one of the most important non-timber products of the Amazon region, since it is a food appreciated by local communities and still used for export. Its almond is recognized throughout the world as the food richest in selenium (Se), with increasing research that increasingly prove its beneficial effects on human health. The nutritional composition of the almond is linked to the accumulated mineral reserve in the tissues of the components of the chestnut tree. In the plant the allocation can happen by different parts, being the receiving organs the root, stem, branches, leaves, flowers and fruits. The objective of this work was to quantify the nutrients and selenium in the different parts of Brazil nut, under different ages and localities, and to determine the levels of minerals and selenium in soils, observing their behavior in relation to local variations. Samples of root, stem, upper branch, lower branch, new leaves and old leaves were collected in the states of Amazonas (21 plants) and Mato Grosso (15 plants), and soil samples in the 0-20 cm, 20-40 cm, 40-60 cm, 60-80 cm and 80-100 cm. The nutrient and selenium concentrations in Brazil nut in the evaluated sites were influenced by the amount and availability of the minerals in the soil, as well as by the genotype capacity of each plant within each population to accumulate the nutrients and If, considering the different with their own environmental particularities. Within the parts of the evaluated tree, the concentration of the majority of the nutrients in greater quantity occurred in the leaves. The concentrated content of selenium in the parts of the tree will depend mainly on the amount of available element in the soil. The root and stem being the most concentrated parts of the study.