Nitrogênio e Selênio em rúcula: da avaliação nutricional à biofortificação

Abstract

Selenium (Se) is considered an essential element for humans and animals, performing essential functions. However, its availability for human nutrition depends on the absorption and accumulation by plants, which impacts their ability to produce food that will be food sources of this element. Hence, it is crucial to understand the dynamics and interaction of this element with other nutrients to understand how adequate Se absorption occurs. The present research aimed to evaluate the development of arugula plants (Eruca sativa L.), macro, micronutrient, and Se contents as a function of the interaction between N and Se, with the goal of agronomic biofortification. The experiment was carried out in a greenhouse at the Department of Soil Science at UFLA, Lavras-MG. The experimental design was completely randomized, in a 3x3 factorial scheme with four replications, with arugula plants (cv. Folha Larga) receiving doses of N (0; 150 and 300 mg dm³) and doses of Se (0; 0.5 and 1.0 mg dm³). After 30 days of transplanting, the plants were harvested as aboveground biomass. Sulfuric digestion was carried out in plant samples, followed by the semi-micro Kjeldahl method to determine N content. Se and other nutrients evaluated were extracted through nitro perchloric digestion in a digester block, and contents were determined by plasma optical emission spectrometry. Data were submitted to analysis of variance (ANOVA) and polynomial regression analysis (p≤0.05). All analyzes were performed using R software version 4.0.3. There was no interaction of N and Se for arugula’s fresh biomass. Among the macro and micronutrients evaluated, only N content was influenced by N and Se interaction. As higher doses of Se were applied, there was a reduction in the N content in arugula plants. However, when evaluating the effects of isolated N and Se, there was an increase in the accumulation of Se and S as increasing doses of Se were applied, indicating synergism between S and Se. Regarding micronutrients, there was a reduction in zinc content when increasing doses of N and Se. In general, arugula plants showed adequate development, being a crop with a high potential to be used in agronomic biofortification, considering the accumulation of Se.