Foliar Application of Calcium Chloride Delays Postharvest Ripening of Strawberry

Abstract

<jats:p>Effects of CaCl<jats:sub>2</jats:sub> preharvest treatment on postharvest strawberry <jats:italic>(Fragaria</jats:italic> × <jats:italic>ananassa)</jats:italic> ripening and gray mold development were assessed. Two experiments were carried out in 1987 on two sites. In the first experiment, the effects of rate of application of CaCl<jats:sub>2</jats:sub> and degree of fruit maturity at treatment were studied with the conventional cultivar Kent. In the second experiment, the influence of concentration and frequency of application of CaCl<jats:sub>2</jats:sub> was investigated with day-neutral `Tribute'. Calcium treatment caused a significant increase in fruit and leaf Ca contents, which were closely correlated. The degree of fruit maturity at application and the frequency of treatment did not affect Ca concentration in the tissues. Several maturity criteria were measured during fruit storage in air at 4C. Anthocyanin and free-sugar contents and tissue electrical conductivity increased, while titratable acidity and firmness decreased. In both experiments, Ca treatment delayed ripening and gray mold development. The delay increased with increasing Ca concentration.</jats:p>

Vacuum Infiltration of Polyamines Increases Firmness of Strawberry Slices Under Various Storage Conditions

“…Increased fruit firmness following postharvest calcium treatment has been previously reported in strawberries (Rosen and Kader, 1989). Foliar sprays of calcium also increased calcium levels and decreased softening of strawberry fruits (Cheour et al, 1991(Cheour et al, , 1990. Polyamines are positively charged, and when applied exogenously, may have similar effects to calcium in terms of delaying senescence and retarding fruit softening in apples (Kramer et al, 1991).…”

Identification of mRNAs with enhanced expression in ripening strawberry fruit using polymerase chain reaction differential display

“…The discovery of a ripening-related annexin is particularly intriguing because of the marked changes in membrane properties and cell wall structure, which are influenced significantly by Ca 2 +, that accompany fruit ripening [15,16]. For example, it is known that the external application of calcium to strawberries and other fruits can significantly impact the degree of softening and the overall rate of ripening [9,16]. It can be speculated that the abundance or distribution of an annexin-like protein might influence ion fluxes, membranecytoskeletal attachments, or other aspects of plasmalemma function that change during fruit maturation and senescence.…”

Managing Crop Disease through Cultural Practices

“…For example, calcium has been shown to inhibit anthracnose (caused by Colletotrichum gloeosporiodes or C. acutatum) in apples (Biggs, 1999) and to decrease post-harvest disease development on strawberry (Cheour et al, 1990), while treatment of tomato with calcium carbonate reduced fusarium crown rot disease (Woltz et al, 1992). In contrast, Nam et al (2006) could fi nd no effect of calcium on anthracnose on strawberry.…”