VASE LIFE AND ELECTROLYTE LEAKAGE OF CUT LISIANTHUS (EUSTOMA GRANDIFLORUM) AFTER TREATING WITH SUCROSE, CITRIC ACID, CALCIUM SULFATE AND SILVER NITRATE

The effects of treating cut lisianthus ‘Mariachi Bleu Fonce’ with solutions of sucrose, citric acid, calcium sulfate and silver nitrate on vase life and electrolyte leakage was evaluated. Preservative solutions with factorial combinations of four concentrations of sucrose (0, 20, 40 and 60 g L^-1), two levels of citric acid (0 and 160 mg L^-1), two concentrations of silver nitrate (0 and 120 mg L^-1) and two concentrations of calcium sulfate (0 and 240 mg L^-1) were prepared and applied to cut lisianthus and vase life, electrolyte leakage and the percentage of opened flower buds were measured. The results showed that with increasing the sucrose concentration the vase life of cut lisianthus increased and the highest vase life was obtained when sucrose was applied with a concentration of 60 g L^-1. The vase life of cut lisianthus was 29 days in the sucrose solution (60 g L^-1) as compared to 15 days for the water control. Application of citric acid and silver nitrate extended the vase life of cut lisianthus for 2 and 4 days respectively as compared to the control plants. Application of 60 g L^-1 sucrose in combination with 160 mg L^-1 citric acid resulted in the highest vase life for cut lisianthus which was 31 days as compared to 15 days for the control plants. Addition of silver nitrate or calcium sulfate to the solution with 60 g L^-1 sucrose + 160 mg L^-1 citric acid was not effective in extending the vase life of cut lisianthus to more than 31 days. The effects of sucrose, citric acid, silver nitrate and calcium sulfate on electrolyte leakage and the percentage of opened flower buds have also been discussed.