Comparison of dyes and preservative solutions on the vase life of Polianthes tuberosa L.

The use of different dyes in changing the color of cut flowers is one of the new and emerging operations in order to increase diversity in the market of buying and selling flowers. In order to investigate the effect of different concentrations of food and industrial dyes on the vase life and physiological traits, an experiment was conducted in the form of factorial design based on a completely randomized basis with 3 replications. The first factor included dyes (control (without color), brilliant blue 4500 mg L-1, carmosin 4500 mg L-1, quinoline yellow 4500 mg L-1, acid orange 7 2500 mg L-1) and the second factor includes the preservative solution (distilled water and preservative solution including citric acid 300 mg L-1 + hydroxyquinoline sulfate 200 mg L-1 + sucrose 5%). The results showed that yellow quinoline dye + pulsing solution had the longest vase life (8 days), petal soluble solids (6.2%), the highest cell membrane stability and the least petal electrolyte leakage (23.5%) and the bacterial population of vase life solution (4.29 log10 CFU/ml). The relative fresh weight showed an upward trend until the second day, then a downward trend was recorded in all treatments. In the investigation of flower opening percentage trait, the orange acid 7 + distilled water treatment performed very poorly (6.87) and showed the lowest vase life (4 days) and the amount of soluble solids (2.52%) compared to other treatments. The control + distilled water treatment had the lowest relative fresh weight, the highest electrolyte leakage of petals (41.4%) and the highest bacterial accumulation in vase life solution (5.86 log10 CFU/ml). It seems that the use of food colors (Brilliant Blue, Carmosine, Quinoline Yellow) along with the use of preservative solution temporarily, in addition to creating variety, by improving the relative fresh weight index compared to undyed flowers and industrial colors (Orange acid 7), has increased the vase life of Polianthes tuberosa flowers.