Postharvest Quality of Beetroots Grown Under Different Irrigation Depths and Ascorbic Acid Doses

Beetroot (Beta vulgaris L.) is a culture of great demand in Brazil due to its high nutritional value. However, water availability is a determining factor on its production. An alternative to reduce the damage caused by water stress is to apply organic solutes, such as ascorbic acid. The purpose hereof was to evaluate the postharvest quality of beetroots grown under different irrigation depths and ascorbic acid doses. The experiment was carried out in the Human, Social, and Agricultural Center’s Postharvest Physiology and Technology Laboratory of the Federal University of Paraíba, Bananeiras, Paraíba, Brazil, in a completely randomized design with five doses of ascorbic acid (0.00, 0.29, 1.00, 1.71, and 2.00 mM) and five irrigation depths (40.0%, 51.6%, 80.0%, 108.4%, and 120.0% of the evapotranspiration), combined according to each Box Central Compound experimental matrix, totaling nine treatments with five repetitions. The variables total soluble solids, electrical conductivity, hydrogenation potential, titratable acidity, total soluble solids and titratable acidity ratio, moisture, dry matter, and mineral matter were evaluated. The data were submitted for analysis of variance and polynomial regression. There was a significant interaction between the irrigation depths and the ascorbic acid doses in every variable, except for electrical conductivity and mineral matter. The postharvest characteristics of beetroots improved with applications of ascorbic acid doses in the thinner irrigation depths. The greatest dose of ascorbic acid (2 mM) in the thinner irrigation depth (40%) increases the postharvest quality of beet tuberous roots.