Effect of Pre-harvest Calcium and Boron Application on the Quality and Shelf-Life of Apple cv. ‘Red Delicious’

Abstract

Field experiments were conducted to study the effect of calcium chloride (0.4%, 0.6% and 0.8%), boric acid (0.2%, 0.4% and 0.6%) and their combinations on apple trees cv. ‘Red Delicious’, applied twice (60 days and 30 days before harvest). Results revealed that among different treatments, maximum fruit weight (192.13 g), fruit length (7.49 cm), fruit diameter (7.64 cm) and fruit volume (185.86 cm³) were observed in treatment T₁₀ (0.6% CaCl₂ + 0.2% H₃BO₃), and the highest TSS (14.56 °Brix), TSS:acid ratio (80.89), total sugar (11.36%), reducing sugar (9.37%), non-reducing sugar (1.83%), chlorophyll content SPAD value (53.75), firmness (7.62 kg cm⁻²), shelf life under room temperature (28.20 days), under refrigeration (93.20 days) and under controlled atmosphere (CA) storage (180.50 days), organoleptic rating out of a 9-point hedonic scale (taste: 8.70, flavour: 8.70 and overall acceptability: 8.60), quality grading out of a 9-point hedonic scale (texture: 8.90, aroma: 8.90, appearance: 8.70, colour: 8.40) out of a 9-point hedonic scale and the lowest titratable acidity (0.18%) were recorded with the application of treatment T₁₁ (0.6% CaCl₂ + 0.4% H₃BO₃). Our results support the use of calcium chloride and boric acid as a promising fertilizer for improving the overall characteristics of apple cv. ‘Red Delicious’.