Nitrogen and phosphate fertilization on the production and growth of seedlings of Euterpe precatoria Mart.

Abstract

The single açaizeiro is a palm tree with excellent potential for expansion of commercial crops. The objective was to evaluate the effect of nitrogen and phosphorus doses on the production and growth of seedlings of Euterpe precatoria Mart. The experiment was set up in a randomized block design, in a 5² factorial scheme, with 5 x 5 treatments (0, 15, 30, 45 and 60 mg dm^-3 of N and 0, 50, 100, 150 and 200 mg dm^-3 of P). Nitrogen was applied in installments (20, 40 and 40% through three top dressings of 40, 100 and 160 days) and simple superphosphate in a single dose mixed with the substrate. At 334 days, after pricking, the height of the seedling was evaluated, stem diameter, root, aerial and total dry masses, Dickson Quality Index, macro and micronutrient content in leaves and soil. The data were submitted to variance analysis and, when significant, a response surface was performed. In the absence of interaction between doses their effect was analyzed by regression. The chemical and physical characteristics of the substrate, seedling biometrics and the foliar macro and micronutrient contents were evaluated using Pearson's correlation. The biometric characteristics of Euterpe precatoria seedlings are influenced by doses of nitrogen and phosphorus. The doses of 60 mg dm^-3 of nitrogen and 200 mg dm^-3 of phosphorus proved to be the most effective, resulting in the best performance for most of the evaluated parameters.