Qualidade de alface crespa cultivada em sistema orgânico, convencional e hidropônico

Abstract

The aim of this work was to evaluate the quality of the looseleaf lettuce group, cv. Vera, in organic, conventional and hydroponic crop in Rio Branco, Acre State, North Brazil. The experiment was carried out in July 2009, at the Universidade Federal do Acre. The samples of the conventional and hydroponic (three trademarks) systems were obtained randomly in supermarkets in Rio Branco, in the same day of harvest of the lettuce produced in the organic system. The organic lettuce grow in the experimental area was cultivated in a greenhouse, under no-tillage and mulching of bamboo leaves, and fertilized with organic compost (17 t/ha on a dry base). The experimental design was completely randomized with five treatments and four replications composed of three plants each. The samples were washed, cut and processed, including leaves and stems to obtain the juice and soon after the soluble solids contents and the concentration of nitrate and ascorbic acid were determined. The three trademarks of hydroponic lettuce had higher nitrate content and lower concentration of soluble solids and ascorbic acid, while the organic lettuce had higher quality, with low concentration of nitrate and higher ascorbic acid content.