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.

RESUMEN Actualmente, debido a la mayor oferta de híbridos de maíz dulce con alto potencial productivo, ciclo más corto y un metabolismo más intenso que el maíz común, hacen que este cultivo sea muy exigente en nutrientes. En ese sentido, el presente trabajo tuvo como objetivo evaluar el efecto de tres dosis de molibdeno (Mo) (150, 300 y 450 g ha-1), vía foliar, en diferentes épocas de aplicación (E1: 100% a los 15 días después de la emergencia - DDE; E2: 100% a los 30 DDE; E3: 100% a los 45 DDE; E4: 50% a los 15 y 30 DDE, y E5: 33,3% a los 15, 30 y 45 DDE), sobre el desempeño agronómico del maíz dulce 'SVN 9298'. Se presentó interacción significativa de los factores sobre la concentración foliar de Mo, obteniéndose el mayor valor con 450 g ha-1 de Mo aplicado a los 45 DDE, siendo equivalente al incremento de 1,2% con relación al contenido foliar observado en las plantas sin aplicación de Mo. También, la concentración foliar del nitrógeno (N) fue mayor con la dosis más alta de Mo utilizada. Los mejores resultados para el número de espigas comerciales (49.477), productividad total de espigas (20.942 kg ha-1) y productividad de espigas comerciales (13.211 kg ha-1) fueron obtenidos con las dosis estimadas de 316, 450 y 311g ha-1 de Mo, respectivamente. Asimismo, la dosis que maximizó la productividad de granos (5.055 kg ha-1), que es el componente más importante que define el desempeño agronómico del maíz dulce, fue obtenida con la cantidad estimada de 334 g ha-1 de Mo.

ABSTRACT Nowadays, there is a greater offer of sweet corn hybrids with a high productive potential, shorter cycle and more intense metabolism than common corn, resulting in this crop being very demanding in terms of nutrients. The present study aimed to evaluate the effect of three levels of molybdenum (Mo) (150, 300 and 450 g ha-1), via foliar spraying, with different application timing (E1: 100% at 15 days after emergence - DDE; E2: 100% at 30 DDE; E3: 100% at 45 DDE; E4: 50% at 15 and 30 DDE, and E5: 33.3% at 15, 30 and 45 DDE) on the agronomic performance of sweet corn 'SVN 9298'. There was a significant effect from the interaction of the factors on the foliar concentration of Mo, obtaining the highest value with 450 g ha-1 of Mo, applied at 45 DDE, with an increase of 1.2% in the foliar content from that observed in the plants without a Mo application. Also, the foliar concentration of nitrogen (N) was higher with the highest Mo level. The highest number of commercial ears (49,583), total productivity of ears (20,942 kg ha-1) and productivity of commercial ears (13,211 kg ha-1) were obtained with estimated levels of 316, 450 and 311 g ha-1 of Mo, respectively. Likewise, the dose that maximized grain productivity (5,055 kg ha-1), which is the most important component that defines the agronomic performance of sweet corn, was the estimated dose of 334 g ha-1 of Mo.