Effect of Blue Light Irradiation and Silver Nanoparticles at Different Rates on the Vase Life and Traits Involved in Postharvest Quality Preservation of Cut Alstroemeria cv. ‘Napoli’

The application of blue light to postharvest cut flowers is a new method to improve their vase life. This research aimed to explore the effect of blue light irradiated for different times (6, 12, 18, or 24 hours) and the pulse treatment of silver nanoparticles (SNP) (5, 10, 15, or 20 mg L-1) on the vase life and the related traits of cut Alstroemeria cv. ‘Napoli’ flowers. The control plants were treated with 3% sucrose. The study was based on a completely randomized design with three replications. The results showed that the longest vase life was 22.66 days obtained from 10 mg L-1 SNP, which did not differ significantly from the treatments of 12 hours of blue light irradiation (22.00 days) and 20 mg L-1 SNP (21.66 days). The lowest fresh weight losses were observed in the treatments of blue light for 18 and 12 hours and SNP at the rate of 10 mg L-1, respectively. The highest dry matter percentage (57.34 %) was related to the plants treated with 10 mg L-1 SNP. The flowers irradiated with blue light for 12 hours had the highest chlorophyll a and b (2.52 and 1.27 mg g-1 FW, respectively), the highest catalase activity (5.26 nmol g-1 FW min-1), and the lowest polyphenol oxidase activity (0.007 μmol g-1 FW min-1). The lowest vase solution bacterial population was obtained from the application of 15 mg L-1 SNP and the highest petal protein from the irradiation of blue light for 24 hours. SNP was effective in controlling Gram-negative bacteria, and blue light was effective in controlling Gram-positive bacteria in the vase solution. It is inferred from the results that blue light, as a physical factor, is effective in preserving the vase life and relevant traits in the cut Alstroemeria ‘Napoli’ flowers.