FOLIAR PREHARVEST CALCIUM TREATMENT INFLUENCE ON YIELD AND QUALITY ATTRIBUTES OF STRAWBERRY

Abstract

The major limiting factors for commercial marketability of strawberries grown in the Northeast is firmness and shelf-life. The major objective of the research is to study basic and applied aspects of exogenous calcium treatments on yield and quality of New Jersey grown berries. In 1990, 8328-1 and 8237-1 (NJUS advanced selections), and `Earliglow' and `Raritan' standards, were treated with 4 foliar Ca sprays (Nutrical) at 10 day intervals from bloom through harvest. In 1991, sprays (3) were applied at bloom, bloom+15 days, and pre-harvest. An `Earliglow' plot was utilized to test timing: bloom, mid-spray, or pre-harvest. Leaf and fruit samples were taken from treated and untreated plots prior to each application. Instron texture tests were performed to quantify firmness; a taste panel evaluated quality (color, texture, flavor, and overall quality). With multiple sprays, there were no significant differences in yield, fruit size, and Brix%, between treatments; however there were significant differences between genotypes and a genotype-by-treatment interaction. The lone bloom spray treatment reduced fruit size. Ethylene was reduced with calcium treatment, respiration was unaffected. Differences in flavor attributes were genotype specific.