Evaluation of diverse types of sugars for enhancing quality and vase life of cut daylilies

This study introduces daylily (Hemerocallis fulva L.) as a cut inflorescence, which could be a potential economic alternative to expensive true lily inflorescences. They can be used for economical designs, such as wedding bouquets. Three different carbohydrate sources were utilized; two types are common (glucose and sucrose), and one is novel (lactose). They were added at 50 gL⁻¹ for each with bleach at 0.5% to the preservative solutions of the cut daylily inflorescences. The experiment was designed using a completely randomized layout. It included four treatments, with five replicates for each. Each replicate consisted of one cut inflorescence rachis. The applied sugars significantly prolonged the vase life of the cut inflorescences compared to the control inflorescences (11 days in both years), extending it by 2 to 4 days, with glucose proving to be the most effective in both years (14.33 and 15 days in the 1st and the 2nd year, respectively). In addition, glucose was able to extend the life of unopened florets by six hours over the life of the control florets. Glucose significantly increased the relative fresh weight and the amount of water uptake. Lactose efficiently maintained water balance and the dry matter of the cut inflorescences. Lactose also increased the scape diameter until the fifth day during the vase life, while it reduced the number of dropping buds to zero in both years. Glucose and lactose had the best effect on the diameter of the florets. Lactose recorded the highest concentrations in the tepal’s total anthocyanin content. Sucrose had the highest values of the tepal’s total flavonoid and total sugar contents. Sucrose effectively diminished the activity of the POD isozyme more than the control and other sugars. The control preservative solution was the most effective in inhibiting the growth of microorganisms, followed by lactose solution, which recorded the lowest microbial growth rate of the three sugars.