Foliar application of zinc in the agronomic biofortification of arugula

Abstract Zinc deficiency affects one third of the population and a possible solution is the agronomic biofortification of vegetables. Due to the increased consumption of arugula, this vegetable has good potential of use; however, there are few researches on the subject. The objective of this study was to evaluate the effect of foliar zinc applications, at different times, on physiological, yield, nutritional, and biofortification parameters of the ‘Broad Leaf’ arugula. Three doses (0.5, 1, and 1.5 kg ha-1 Zn) were evaluated at five times (15; 20; 25; 15 and 20; and 15, 20 and 25 days after emergence) and a control treatment. It was observed that there was no effect of the application on the physiological variables, as well as on the height, leaf area, and fresh mass of aerial parts of the plant. Zn sprayings affected the N contents, while for Mn, P, Cu, and Fe, no significant effects were found. It was verified that with the application of 1.5 kg ha-1 Zn made at 25 days after emergence, a higher Zn content was obtained in the arugula leaves, representing an increase of 279% in relation to the control, showing the effectiveness of foliar zinc applications as an agronomic biofortification strategy for arugula.