Effect of Fertigation on the Physicochemical Quality and Antioxidant System of ‘Fino’ Lemons during Postharvest Storage

Abstract

Fertigation is a technique of injecting fertilizers along the irrigation lines, allowing a precise control of the moisture and the application. Nowadays, the main fertilizers used are nitrogen and potassium. Usually, an excess of fertigation is applied to achieve an early harvest of the lemon fruit. However, there is no literature available regarding the effects of excess fertigation on lemon fruit quality and antioxidant systems at harvest and during cold storage. Therefore, the present study aims to investigate these effects. This experiment was developed by comparing two plots: the first one with standard fertigation (SF) and the second one with intensive fertigation (IF). The yield per tree in the early harvest was higher in the IF than the SF plot; however, total yield was similar under both fertigation strategies. Lemons from the SF plot maintained higher total phenolic content and total antioxidant activity compared with lemons from the IF plot. In addition, firmness, total soluble solids and titratable acidity were also higher in SF lemons. Furthermore, weight loss, ethylene production, colour (parameter a*) and decay incidence were reduced in lemon fruits from the SF plot. Early lemons harvested from the standard fertigation plot showed high physicochemical quality and antioxidant properties, reducing lemon fruit decay during cold storage and providing high-quality fruits to consumers.