Pre-harvest application of salicylic acid and n-propyl gallate for enhancing shelf-life of guava

Abstract

Present investigation was conducted to evaluate the efficacy of pre-harvest application of salicylic acid (SA) and N-propyl gallate (n-PG) for enhancing the postharvest shelf-life and quality of winter guava fruit cv. Allahabad Safeda during two seasons. Pre-harvest application of aqueous solutions of salicylic acid (150, 300, 450 ppm) or N-propyl gallate (100, 200, 300 ppm) was done at 2 and 4 weeks before harvest. Fruits were harvested during third week of December at the firm mature stage, packed in corrugated fibre board boxes with newspaper lining and stored in a walk-in-cold room maintained at 6-8°C and 90-95% RH. Fruits were analyzed at weekly intervals to evaluate various quality attributes. In control fruits harvested from untreated trees, weight loss and decay incidence increased, whereas, firmness, ascorbic acid, acidity, total phenols and pectin content decreased during the storage. Fruits treated with n-PG (300 ppm) showed minimum decay incidence (16.55%), reduced pectin methylesterase activity (2.96 μg/ g FW), enhanced firmness (66.1 N ), total soluble solids (9.96°Brix), acidity (0.35%), pectin (1.16% calcium pectate) and phenol contents (145.58 mg GAC/ 100 g pulp), and also maintained highly acceptable organoleptic rating up to 3 weeks of storage. Fruits subjected to SA treatments were intermediate in quality attributes between that of the control and n-PG treated fruits.