Salinidade e estratégias de manejo da solução nutritiva no cultivo da rúcula

Abstract

The presence of brackish water in the Brazilian semi-arid, which is used for the diffuse communities, requires that the reduced cost allows the use of the resource for the cultivation of vegetables commonly used in the region. Thus, the objective of this work was to evaluate the management of nutrient solutions prepared in brackish waters, aiming to validate the cultivation of rocket (Folha larga cv.) in low cost hydroponics, whose main focus is the use in diffuse communities by the Brazilian semi - arid. To do this, two experiments were carried out in which the use of six salinity levels of the nutrient solution (1.5, 3.0, 4.5, 6.0, 7.5 and 9 dS m-1) and two circulation frequencies (2 and 3 times a day, namely at 8 and 16 hours and at 8, 12 and 16 hours), but in Experiment I, the evapotranspiration was replaced with the brackish water used in the preparation of the nutrient solution and in Experiment II the water was filled with water (0.1 dS m 1). These treatments were distributed in a completely randomized experimental design, analyzed in a 6 x 2 factorial scheme, with five replications. In this way, there were lower losses in the hydric relations and in the biomass production of the aerial part of the rocket, when it was replaced with water supply, in addition, the consumption and the efficiency of water use were reduced by the saline increment, independently of the strategy of replacement of the evapotranspirated sheet. Both for replenishment with water supply and brackish water, the increase gives electrical conductivity of the nutritive solution provided a decrease in the production of flesh and dry biomass, in the percentage of dry mass an in the biometry of the plants. The increase in the frequency of circulation did not influence the biometric variables, however, under a higher frequency of circulation the plant prioritized the development of the biomass of the aerial part in detriment of the root.