Desenvolvimento e nutrição mineral de plantas de gérbera em função da condutividade elétrica

The control of substrate salinity is important for agricultural crops and, among the methods used, is the management of electrical conductivity of the substrate solution, which can be used as an indirect measure of the amount of salts and nutrients available or not for the plants. The objective of this study was to assess the effect of EC levels on the development, concentration and accumulation of nutrients in potted (1.3 L) gerbera (Gerbera jamesonii). The study was conducted in a greenhouse in a randomized block design, with five treatments (EC of 1.0, 2.0, 3.0, 4.0 and 5.0 dS m-1) and four replications. The quadratic function of the applied EC was obtained for leaf number and diameter, and the linear function, for inflorescence diameter. The nutrients in plant tissue increased linearly with the increasing level of EC, except for potassium and sulfur. The decreasing order for macronutrient levels was K>N>Ca>P>Mg>S, indicating the importance of potassium. Production parameters were little affected by the concentration of the nutrient solution. Therefore, it can be concluded that, with the increase in nutrients as a function of EC elevation, a luxury uptake can occur, with no representative on qualitative aspects.