Postharvest life of cut narcissus in depth: differences of flower tissues longevity and stem structure anatomy.

BACKGROUND: Despite extensive research on extending the vase life of narcissus, the internal mechanisms-particularly the physiological, biochemical, and anatomical traits-that govern its postharvest longevity remain insufficiently understood. This study examined ten Iranian narcissus populations grown under uniform greenhouse conditions to identify floral and stem traits associated with variation in vase life. Longevity was measured separately for inflorescences, petals, and coronas, while biochemical and physiological attributes were compared between petal and corona tissues and structural changes were assessed in stems during postharvest storage.

RESULTS: Corona tissues exhibited more than twice the longevity of petals and maintained higher relative water content, protein levels, and antioxidant enzyme activity, alongside lower lipid peroxidation, indicating greater resilience to oxidative and hydration-related stress. Anatomical analysis of stem cross-sections revealed progressive tissue shrinkage and parenchyma collapse during vase life, with no evidence of vascular occlusion in any population. Principal component analysis further identified carotenoid concentration, tissue thickness, antioxidant activity, hydration status, and vascular-bundle geometry as the major multivariate dimensions associated with extended vase life.

CONCLUSION: These observations suggest that carotenoid accumulation represent an important biochemical feature associated with extended vase life. The anatomical changes show that postharvest hydraulic decline in narcissus stems is related with cell collapse and vascular tissue shrinkage. These observations are triggered by wounding at the cut surface and potential stress from continuous stem base submersion, and they are comparable with vascular occlusion. Collectively, these findings demonstrate that postharvest performance in narcissus is shaped by coordinated biochemical, hydraulic, and structural traits, providing a physiological and anatomical basis for improving postharvest handling and guiding future studies on flower longevity.