African Journal of
Agricultural Research

  • Abbreviation: Afr. J. Agric. Res.
  • Language: English
  • ISSN: 1991-637X
  • DOI: 10.5897/AJAR
  • Start Year: 2006
  • Published Articles: 5784

Full Length Research Paper

Nutritional quality of tomatoes as a function of nitrogen sources and doses

Natália Silva Assunção
  • Natália Silva Assunção
  • Universidade Federal de Viçosa, Campus Rio Paranaíba. Rodovia MG 230 Km 10, Cx Postal 22, CEP-38810-000. Rio Paranaíba, MG - Brasil.
  • Google Scholar
Maria Elisa de Sena Fernandes
  • Maria Elisa de Sena Fernandes
  • Universidade Federal de Viçosa, Campus Rio Paranaíba. Rodovia MG 230 Km 10, Cx Postal 22, CEP-38810-000. Rio Paranaíba, MG - Brasil.
  • Google Scholar
Leonardo Angelo Aquino
  • Leonardo Angelo Aquino
  • Universidade Federal de Viçosa, Campus Rio Paranaíba. Rodovia MG 230 Km 10, Cx Postal 22, CEP-38810-000. Rio Paranaíba, MG - Brasil.
  • Google Scholar
Flávio Lemes Fernandes
  • Flávio Lemes Fernandes
  • Universidade Federal de Viçosa, Campus Rio Paranaíba. Rodovia MG 230 Km 10, Cx Postal 22, CEP-38810-000. Rio Paranaíba, MG - Brasil.
  • Google Scholar
Natalia Oliveira Silva
  • Natalia Oliveira Silva
  • Universidade Federal de Viçosa, Campus Rio Paranaíba. Rodovia MG 230 Km 10, Cx Postal 22, CEP-38810-000. Rio Paranaíba, MG - Brasil.
  • Google Scholar


  •  Received: 30 October 2017
  •  Accepted: 20 December 2017
  •  Published: 10 May 2018

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 Viçosa - Paranaíba Campus, in Rio Paranaíba (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.