Improving vase life and qualitative properties of cut lisianthus (Eustoma grandiflorum (Raf.) shinn.) by Tragacanth gel and hot water

Lisianthus (Eustoma grandiflorum (Raf.) shinn.) is one of the most important cut flowers in the world. However, a relatively short vase life reduces its marketability. Usually Tragacanth gel and hot water treatment is applied in fruits and there are a few reports in cut flowers too. The aim of the present study was to evaluate the effects of tragacanth gel and hot water treatments in extending vase life and increasing the qualitative properties of cut flowers of lisianthus. For this purpose an experiment was conducted based on completely randomized design with thirteen treatments including three levels of tragacanth (1, 2.5 and 5%) in two ways (pulsing and continues), hot water in 35 and 45 °C for 2, 5 and 10 min and control with three replications,. The highest vase life, flower weight and the lowest bacteria population were obtained in 2.5 % tragacanth pulse treatment. Maximum catalase and peroxidase activity was obtained in 1% continues tragacanth treatment. The highest relative water content of leaves and petals was observed in hot water in 35 °C for 2 min and 2.5 and 5% continues tragacanth treatment, respectively. The highest ion leakage was observed in 2.5 and 5% continues tragacanth treatment. The lowest ion leakage was obtained in hot water in 45 °C for 2 min. Generally, both tragacanth and hot water treatments were effective on extending vase life and improving quality properties of lisianthus, but tragacanth pulse treatment showed the best effects.