Efficiency of Application of Selenium in Biofortification of Potato Tubers (Solanum tuberosum)

This study investigated the dose and form of application of sodium selenate (Se) that allows the translocation and accumulation of this element in the edible fraction of potato. Concentrations of Se applied to the soil and leaves were evaluated considering the physiology, total antioxidant activity (TAA), agronomic attributes and Se content in tubers. The spatial distribution of Se was evaluated by X-ray fluorescence spectrometry microanalysis (μ-XRF). Soil application of Se did not significantly affect photosynthetic variables, TAA and yield attributes. However, foliar application caused phytotoxicity in the aerial part, at all doses tested, which reduced yield and caused losses of approximately 172.8 g of tubers per pot. Se content increased in tubers with increasing concentration of sodium selenate, regardless of the application form. μ-XRF analysis showed that Se uptake is not limited to the tuber peel. Potato plants translocated Se from the soil and leaves and accumulated this element inside the tubers. So, when Se is applied into the soil at 0.50 mg dm−3, potato plants accumulate it in the edible portion of tubers. Although foliar application resulted in accumulation of Se inside the tubers, caution is recommended in choosing the dose, due to the sensitivity of potato to this element.