Efficacy of postharvest sodium nitroprusside application to extend storability by regulating physico-chemical quality of pear fruit.

Quality loss in pear fruit during storage reduces its marketability for long run. To increase its storability, the efficacy of postharvest dip treatment donor sodium nitroprusside (SNP) 0.000, 0.001, 0.002 and 0.003 mol L-1 were investigated on pear fruit cv. Patharnakh under storage conditions (low temperature 0-1 °C and relative humidity (90-95%). SNP effectively lowered fruit mass loss, retained colour and higher firmness, suppressed browning and respiration rate and sustained soluble solids content, titratable acidity, total phenol content and ascorbic acid thus conserved the fruit quality for longer period. SNP treatments suppressed the activity of polyphenol oxidase and increased activity of superoxide dismutase enzyme. Additionally, the SNP treated fruit exhibited lesser activities of fruit softening enzymes like pectin methylesterase, polygalacturonase and cellulase. Among all, 0.002 mol L-1 SNP concentration was superior to lengthen storability and sensory quality of pear up to 60 d under cold storage.