Plant growth regulators improved cutting induced physio-biochemical responses to postponement senescence in chrysanthemum

The marketability of cut flowers relies on its postharvest longevity, making it crucial to develop technologies that can extend its vase life. The vase life in chrysanthemum is dependent upon floret senescence and leaf yellowing. In view of extending the vase life, the present study elucidates the implication of plant growth regulators viz. benzyl adenine (BA), thidiazuron (TDZ) and salicylic acid (SA) on postharvest performance and flower longevity of chrysanthemum stems. The harvested stems were treated with various concentrations viz. BA and SA at 50,100,150 and 200 µM and TDZ at 5,10,15 and 20 µM. Treatments containing 10 µM TDZ and 100 µM BA were most effective in improving the longevity (23.35 and 20.32 days respectively) of cut chrysanthemum stems. However, TDZ outplayed BA followed by SA extends the flower longevity through the maintenance of higher physiological and biochemical characteristics. Cluster analysis inferred that the treatments of 50 and100 µM BA and 5 and10 µM TDZ were found to be efficient in delaying floret senescence (24.01 days) and leaf yellowing (20.54 days) in cut chrysanthemum stems. Postharvest longevity exhibited a positive correlation with antioxidant activities, total soluble sugars and proteins, while it showed a negative correlation with anthocyanin and carotenoid contents. The results have demonstrated that use of growth regulators such as benzyl adenine, thidiazuron and salicylic acid may preserve the quality of cut chrysanthemum stems and delay their senescence