Acessibilidade / Reportar erro

NITROGEN AND POTASSIUM FERTILIZATION IN ‘PALUMA’ GUAVA TREES: I. EFFECT ON PRODUCTIVITY AND FRUIT QUALITY FOR INDUSTRIALIZATION

ABSTRACT

The nutrition of the orchards is the major factor of productivity, being necessary to know the proper doses of fertilizers and their influence on fruit quality attributes for industrialization. This study evaluated the effects of different doses of nitrogen and potassium on the productivity of guava trees and also on the values of pH, soluble solids (SS), titratable acidity (TA) and pulp/kernel ratio of guavas. The experiment was conducted at Vista Alegre do Alto, SPin an irrigated ‘Paluma’ guava orchard, 7 years old, managed with pruning during three consecutivecycles of production. The soil of the area was dystrophic Ultisol. The experimental design was the randomizedblocks, in factorial, with four nitrogen doses (0, 0.5, 1 and 2 kg of N plant-1) and four of potassium (0, 0.55, 1.1 and 2.2 kg of K2O plant-1), with three replications. Nitrogen fertilization increased productivity and the pH of the fruit, being explained by the quadratic polynomial regression models; reduced linearly the pulp/kernel ratio and do not influenced the SS and TA values. On the other hand, potassium fertilizationand N x K interaction had no significant effects on productivity and the other characteristics evaluated.

Psidium guajava; guava; nitrogen; potassium


Sociedade Brasileira de Fruticultura Via de acesso Prof. Paulo Donato Castellane, s/n , 14884-900 Jaboticabal SP Brazil, Tel.: +55 16 3209-7188/3209-7609 - Jaboticabal - SP - Brazil
E-mail: rbf@fcav.unesp.br