Foliar Calcium Applications for Controlling Fruit Disorders and Storage Life in Deciduous Fruit Trees

Abstract

Calcium is involved in several disorders and influences the storage life of different fruit species. Moreover, applying preharvest foliar Ca spray is a standard practice to control fruit Ca concentration in certain deciduous fruit trees. Conversely, the effects of foliar Ca spray on the Ca concentration in fruit and the incidence of disorder are sometimes inconsistent. This article provides an overview of recent works on foliar Ca application and discusses Ca application inconsistencies. Foliar Ca sprays reduced bitter pit, enhanced fruit firmness and storage time, and sometimes reduced the incidence of brown rot during storage in apples; reduced internal browning during storage and the incidence of brown rot in peaches; decreased postharvest decay and cork spot in pears; and increased shelf life in grapes. Experiments using 45 Ca or isolated cuticular revealed the effects of fruit growth stages, atmospheric conditions, and adjuvants on Ca penetration. Finally, three possible reasons for inconsistencies of foliar Ca application are discussed.