Assessing the nutritional status of Southern Brazilian Eucalyptus plantations by the CND method

Abstract

Genus Eucalyptus can be grown in different soils worldwide, although it is not always ready to fulfill plants’ nutrient demands. Whenever such nutrient shortage happens, it is necessary applying the nutrients missing, which can be established based on the critical levels and sufficiency ranges (SRs) of nutrients in leaves or by multivariate mathematical models, such as the composition nutrient diagnosis (CND). This study aimed to investigate the nutritional status of Eucalyptus plantations in Brazil, based on the CND method. A total of 119 12-month-old Eucalyptus saligna (E. saligna) plantations were sampled in the Rio Grande do Sul State (RS), Southern Brazil. Nutrient concentration in leaves and the diameter at breast height (DBH) was measured. The E. saligna nutritional status was calculated through the CND method. High- and low-yield populations were set based on DBH of 4.2 cm. The SRs proposed by the CND method were narrower than the ones proposed by official recommendations for Eucalyptus, especially for magnesium (Mg), boron (B), and iron (Fe). The CND-r2 index recorded for each nutrient generated a limitation order for nutrients. The greater accuracy of the recommendations proposed by the CND method, compared with univariate and bivariate methods, contribute to reducing the use of fertilizers.