Influência do silício via foliar na nutrição nitrogenada da berinjela.

Abstract

The eggplant (Solanum melongena L.) is a vegetable fruit that belongs to the solanaceous family,considered demanding in nitrogen (N) for adequate production. Our working hypothesis is that of silicon (Si) may increase the efficiency of nitrogen fertilization and reduces the doses to be applied. Aimed to evaluate the effect of doses of silicon and nitrogen on growth, yield and fruit quality of eggplant. The experiment were conducted at the Centro de Ciências e Tecnologia Agroalimentar (CCTA/UFCG), Campus Pombal - PB, with eggplants cultivate "Embu". The treatments consisting with five the N rates (25, 125, 250, 350 and 500 mg dm-3) and two Si rates (silicon and without foliar application of a 10 mmol L-1 Si) completely randomized design, in a 5 x 2 factorial arrangement with three replications. During pre-flowering, were evaluated growth, gas exchanges the contents of fractional nitrogen (NO3 -, NH4 +, and total and organic), the estimated N use efficiency (NUE) and Si content in the leaves, number of fruits per plant, yield per plant, average fruit weight, the longitudinal and transverse diameter, firmness, °Brix, the pH of the pulp, the vitamin content C and titratable acidity. Nitrogen fertilization of eggplant favored their growth, gas exchange and all fractions of nitrogen in the tissues, but had no effect on the production set of fruits. Silicon fertilization did not affect the growth or the nitrogen nutrition of eggplant, but affected the quality and increased fruit production, independent of nitrogen fertilization.