Salicylic acid and nutrient sprays to improve apple fruit quality

Abstract

Maturity at harvest is one of the most important properties that determine the final quality of the apple fruit. Appearance, texture, flavour and nutritional value are qualities that consumers evaluate empirically to decide whether to eat the fruit again. Within agricultural practices in and out of the orchard, the relationship between plant nutrition and fruit quality is important, and proper nutrient balance is essential to maintain fruit quality. This research work was carried out on ‘Golden Delicious’ and ‘Red Chief’ apple trees. A 56 factorial arrangement was used, with 5 concentrations and 6 factors, 25 treatments in a Taguchi L25 structure. Improvements were found in parameters for fruit finish and fruit quality. The factors with the greatest positive effect on quality in order of importance were Salicylic Acid (SA) 1.0 mM, Potassium (K) 58.90 mM, Molybdenum (Mo) 0.516 mM, Calcium (Ca) 70.00 mM and Cobalt (Co) 8.248 mM and in order of importance the following variables: TSS/acidity ratio, total soluble solids TSS, antioxidant capacity (AC), total phenols (TF), and titratable acidity (TA) in ‘Golden Delicious’ apple. Considering ‘Red Chief’, the factors Ca 70.00 mM, K 58.79 mM and SA 1.0 mM, with the variables; TA, TSS/acidity ratio, TF, TSS and AC that finally lead to an optimal development of finish and quality in the apple fruit.