The Effect of Foliar Application of Calcium Nitrate and Potassium Phosphite on Antioxidant Enzymes and Nutrients of Blood Orange CV. Sanguine in the Storage

Citrus fruits are important sources of antioxidants including phenolic compounds, flavonoids, carotenoids and ascorbic acid, which can be changed by using mineral elements, especially potassium and calcium. This research was conducted factorial form in a completely randomized design. Foliar application of calcium nitrate (0, 2 and 4 g L-1) and potassium phosphite (0, 1.5 and 3 g L-1) before commercial maturation of blood orange fruits of Sanguine cultivar, and one week after treatment, fruit harvesting operation done. The fruits were stored for 3 months in normal storage. The antioxidant properties, elements and enzymes were evaluated at the time of harvest and during the storage period at intervals of one month. The results showed that the use of higher concentrations of calcium nitrate and potassium phosphite improved the characteristics measured on the day of harvest. Fruits treated with 4 g L-1 calcium nitrate and 3 g L-1 and 1.5 g L-1 potassium phosphate had the best effect on antioxidant properties and elements. Also, the amount of APX and SOD enzymes increased with these treatments during the storage period.