“Blossoming Beyond Time:” Proline orchestrates flower senescence in Ranunculus asiaticus L. by modulating biochemical and antioxidant machinery

Abstract

Postharvest senescence presents a formidable obstacle to the economic viability of cut flowers, necessitating meticulous preservation strategies within the cut flower industry. This study meticulously examines the efficacy of exogenously applied proline in enhancing floral longevity in Ranunculus asiaticus cut flowers, while also exploring the underlying physiological and biochemical mechanisms. Floral buds harvested at the half-open stage, were systematically allocated to five clusters for experimentation. The cluster of flowers specified as control was held in distilled water, whereas rest of the clusters received varying concentrations of proline (2 mM, 4 mM, 6 mM and 8 mM). Remarkably, the application of 6 mM proline proved most effective, significantly extending flower lifespan by approximately four days compared to the control. This longevity enhancement correlated with notable increases in floral diameter, soluble proteins, sugars and phenols. The findings indicate a pivotal role of exogenous proline in alleviating oxidative stress within petal tissue, as evidenced by reduced lipoxygenase activity and enhanced antioxidant enzyme activity. Furthermore, a decrease in lipid peroxidation was observed alongside heightened membrane stability, as measured by the membrane stability index. Conclusively, proline treatment emerged as a promising postharvest intervention in enhancing longevity of Ranunculus asiaticus flowers by modulating underlying biochemical mechanisms.