Antitranspirant compounds alleviate the mild-desiccation-induced reduction of vase life in cut roses

The vase life sensitivity to mild desiccation (12% weight loss) was addressed in rose, together with alleviation possibilities. The postharvest longevity upon arrival or following mild desiccation was determined on eight cultivars, combined with several morpho-physiological traits. Mild desiccation significantly decreased (10-39%) the vase life of six cultivars (termed sensitive), whereas it did not affect the vase life of two (thus tolerant). More severe desiccation (>12% weight loss) shortened the vase life of a tolerant cultivar. Stomatal control of water loss explained a large part of vase life variation following mild desiccation, whereas cut flower ability to rehydrate or pedicel rigidity (strength, wood density) did not significantly contribute to this variation. Four potentially-mitigating treatments were further tested on the three most sensitive to mild-desiccation cultivars. Antitranspirant treatments [SNP (elicitor of NO) or acetylsalicylic acid in vase water or darkening] decreased the cut flower water loss during the postharvest phase and alleviated the mild-desiccation-induced reduction in vase life. In contrast, Tween 20 (wetting agent) in the vase water shortened vase life. It is concluded that the vase life of previously desiccated cut roses can be extended by employing treatments that reduce the postharvest water loss.