The effect of preharvest Ca treatment on concentration of polyphenols and antioxidant capacity of ‘Pirja’ and ‘Maikki’ apples grown on different rootstocks

The aim of the experiment was to determine the effect of preharvest CaCl2 treatment on the concentration of certain polyphenols (catechin, chlorogenic acid, phloridzin, quercetin, quercetin galactoside, quercitrin and cyanidin glucoside) and on total antioxidant capacity (TAC) in ‘Pirja’ and ‘Maikki’ apples grown on rootstocks M.26 and B.396.The results showed that the Ca treatment affected the concentration of polyphenols in apples from B.396 and M.26 differently; on B.396, the Ca treatment increased the concentration of quercitrin in apples of both cultivars, whereas on M.26, it decreased the concentration of quercitrin. Quercitrin, quercetin galactoside and quercetin were the major polyphenols contributing to the apple TAC. The concentration of these polyphenols was increased by higher fruit Ca and lower N concentration in ‘Maikki’.

► ‘Pirja’ and ‘Maikki’ apples, grown on M.26 and B.396, were sprayed with CaCl2. ► The Ca treatment affects the concentration of polyphenols and apple antioxidant capacity. ► The effect of rootstock should also be considered. ► Quercitrin, quercetin galactoside and quercetin affected apple antioxidant capacity. ► Higher Ca and lower N concentration increased the concentration of polyphenols in ‘Maikki’.