Osmocote® provides better seedlings of Calophyllum brasilienese Cambess

Abstract

Seedlings of forest species are essential for the implementation of reforestation projects for commercial or environmental purposes and/or restoration of degraded areas. Among the factors with great prominence in the production of seedlings, there are fertilizers. Currently, the use of controlled-release fertilizers is widely used since it provides quality seedlings. The objective was to evaluate the effect of different doses of Osmocote^® on the growth and nutrition of Calophylum brasiliense seedlings. The experiment was carried out in a completely randomized design, with five increasing doses of Osmocote^® controlled-release fertilizers (0.0; 2.0; 4.0; 6.0 and 8.0 g L^-1). Each treatment used 10 replicates (one plant per replicate). At 120 days after transplanting, the evaluation of morphological parameters of the seedlings and nutritional analysis of the aerial part (leaves) were carried out. The 4.0 g L^-1 dose provides the best response for the variables height, stem diameter, number of leaves, shoot and root dry mass and Dickson's quality index. The use of doses below 4.0 g L^-1 or above 6.0 g L^-1 decreased the quality of C. brasiliense seedlings. The nutritional analysis indicated a quadratic behavior for the macronutrients P, F, S and Mg, with the exception of N and Ca (linear). For micronutrients, the behavior was linear for B and Fe and quadratic for Mn and Zn with increasing Osmocote^® dose. In summary, the 4.0 g L^-1 dose of Osmocote® improved the nutrition and quality of C. brasiliense seedlings.