Mineral composition of leaves of guava cv. Paluma as a function of nitrogen-sulfate fertilization

Abstract

Determining the correct nutrient supply of cultivated plants is fundamental to obtain high yields, especially for guava, an important fruitcrop for Brazil whose fertilization is still based on empirical methods. In this way, the effects of ammonium sulfate doses (0; 1,25; 2,5; 3,9 e 5,0 kg ha^-1), applied through irrigation water, on the macro and micronutrient leaf concentrations of guava (Psidium guajava L. cv. Paluma) were evaluated. The experiment was carried out in the municipality of Remigio, Paraiba State, Brazil with treatments distributed in a randomized block design, with four replications. After 22 days of transplanting, guava plants were adequately supplied with N, Mg, S, Fe, Mn e Zn, but deficient in Ca, B and Cu. Potassium supply was optimum, except for control treatment, while phosphorus was sufficient only for the 3,90 kg ha^-1 dose. The nitrogen-sulfate fertilization affected N, P, K, Ca, Mg, Fe and Mn leaf content, but had no influence on B, Cu and Zn concentration leaf.