English

Abstract

Vegetable consumers are increasingly demanding high quality products. Among factors that can influence the nutritional quality of tomato fruits, mineral nutrition stands out. The objective of this study was to evaluate the effect of nitrogen sources and doses on the nutritional quality of tomato fruits. The experiment was carried out in pots in an experimental area at the Universidade Federal de Vicosa - Paranaiba Campus, in Rio Paranaiba (Minas Gerais State, Brazil). The commercial hybrid Dominador was cultivated with four plants per pot. The treatments consisted of nitrogen fertilizer doses with 50 and 200 mg dm-³ of N, combined with four sources (urea, ammonium sulfate, ammonium nitrate and calcium nitrate), in a randomized block design with four repetitions. A (4 x 2) + 1 (four sources combined with two doses of N, plus one treatment without the application of N) factorial scheme was used. We evaluated the increase in oBrix and titratable acidity values with the increase of the N dose applied. Urea and the ammonium nitrate resulted in higher pH values in the tomato fruits. The potassium, lycopene and total carotenoid contents in the tomatoes did not present significant differences in relation to the sources and doses used. The sources and doses of nitrogen fertilizers affected the nutritional quality of the tomato fruits, influencing parameters such as oBrix, pH, titratable acidity and sodium content. Key words: Mineral nutrition, Solanum lycopersicum, nutritional value.