Petal saturation affects visible flower senescence in cut lilies.

摘要

Vase life of cut lily flowers is limited by fading of petal color before abscission. As petal color changes continuously, it is difficult to determine when vase life ends. We investigated the relationship between declines in ornamental value (visible flower senescence) as judged by human subjects and petal color throughout vase life using cut flowers of the yellow lily. We also examined petal dry weight and thickness to clarify the temporal relationship between visible flower senescence and physiological petal senescence. Our results showed that visible flower senescence was sensitive to changes in petal saturation, which was reflected by the chroma value. The chroma value started to decrease in association with a decline in total carotenoids from day 4 after anther dehiscence. Visible flower senescence was marked on the sixth day when the lilies lost their ornamental value rapidly and their vase life came to an end. On the other hand, signs of physiological petal senescence were evident from the first day when petal dry weight and thickness started to decrease gradually. The progress of physiological petal senescence was reflected in the change in hue angle, which represents the color phase. Our results suggest that changes in the chroma value of yellow lily petals reflect visible flower senescence, which affects vase life. The onset of visible flower senescence is delayed by 3 days relative to physiological petal senescence due to maintenance of adequate carotenoid contents in petals during the early stage of flowering.