Modulation of senescence in Alstroemeria: effects of LED Light and preservative solutions on postharvest performance

The inherently short postharvest longevity of Alstroemeria spp. floral stems represents a significant challenge for the floriculture sector, particularly due to rapid leaf yellowing, tepal abscission, and consequent loss of visual quality. This study aimed to evaluate the effects of different LED light spectra and preservative solutions on the postharvest performance of Alstroemeria cv. Pompeii floral stems. The experiment was conducted using a factorial design consisting of five light spectra (red, blue, white, 2 red:1 blue, and 2 blue:1 red) combined with nine preservative solutions, including pulsing treatments with silver thiosulfate or gibberellin associated with holding solutions containing gibberellin, melatonin, or benzyladenine, in addition to a distilled water control. The evaluated parameters included vase life, water relations, chlorophyll content, and petal color. The results demonstrated that pulsing with silver thiosulfate combined with gibberellin was the most effective treatment for preserving postharvest quality, significantly extending vase life and delaying senescence. Gibberellin pulsing also showed satisfactory performance by extending vase life and delaying leaf yellowing, therefore representing a viable and non-toxic alternative. Furthermore, exposure to red LED light improved water balance, maintained petal color stability, and reduced chlorophyll degradation.