Preharvest chitosan applications enhance prune storage performance

Applying chitosan oligosaccharides before harvest may offer an effective strategy to extend prune shelf life and preserve fruit quality during long-term storage. This conclusion comes from a study conducted on French prune cultivars grown in Xinjiang, where researchers evaluated the effects of different chitosan concentrations on postharvest performance.

The treatments were applied as foliar sprays during several stages of fruit development, including fruit set, enlargement, color change and ripening. Concentrations of 0.5, 1.0 and 2.0 g/L were tested. After harvest, the fruit was stored for 90 days at 1 °C under relative humidity conditions of 90–95 %.

The treated prunes consistently maintained better quality attributes than untreated fruit throughout storage. Higher firmness, greater titratable acidity and increased soluble solids content were recorded, indicating improved retention of sensory and commercial quality.

The chitosan treatments also reduced surface darkening, lowered respiration rates and minimized weight loss, all of which contributed to extending marketability. Among the tested concentrations, 1.0 g/L delivered the most effective results, producing substantial improvements in firmness, acidity and soluble solids while significantly reducing respiration and dehydration compared with the control group.

From a physiological perspective, the treatment promoted the accumulation of antioxidant compounds such as ascorbic acid and glutathione, which play an important role in protecting plant tissues from oxidative stress.

Researchers also observed enhanced activity of several antioxidant enzymes, including superoxide dismutase, catalase, peroxidase, ascorbate peroxidase and glutathione reductase. At the same time, the production of reactive oxygen species and compounds associated with cellular damage and tissue aging was significantly reduced.

According to the authors, preharvest applications of chitosan oligosaccharides help regulate antioxidant metabolism during storage, improving fruit preservation and maintaining the postharvest quality of prunes over extended storage periods.

Source

Li, W. B., Zhang, X. Q., Zhao, Y. T., Fan, Y. Q., Zhang, X., Wu, Y. J., & Zhu, X. (2026). Effect of preharvest spraying of chitosan on antioxidant metabolism and storage quality of postharvest prunes. Northern Horticulture. CAB International.