Impact of preharvest putrescine treatment on quantitative, qualitative traits and postharvest vase life of Lisianthus (Eustoma grandiorum cv. Miarichi Grand white) cut flowers

This experiment was conducted to evaluate the effect of foliar application of putrescine on the pre-harvest stage on vegetative quality and postharvest attribtes of Lisianthus ‘Miarichi Grand white’ cut flowers. Plants were planted in the pots containing soil, sand and peat with a volume ratio of 1: 1: 1. The pre-harvest putrescine treatments by 0 (distilled water), 0.5, 1, and 2 mM were applied as foliar spray at the stage of bud initiation. Vegetative quality attributes such as number of flower bud, flower bud length and diameter, flower stem length, flower stem fresh and dry weight, leaf area and chlorophyll content were measured. Results showed that application of putrescine increased number of flower bud, flower bud length and diameter, flower stem length, flower stem fresh and dry weight, leaf area and chlorophyll content compared to the control. Also, putrescine at 2 mM was the most effective treatments in this study. To investigate the effects of preharvest putrescine on postharvest characteristics of Lisianthus cut flowers, the flowers were harvested when two flowers were fully opened. The results showed that pre-harvest treatment led to increase vase life, relative fresh weight and relative water uptake compared to the control. Also, the decrease in ionic leakage, less accumulation of malondialdehyde, reduced enzyme activity lipoxygenase, less accumulation of H2O2 and increase of antioxidant enzymes catalase and ascorbate peroxidase in the concentration of 2 mM putrescine were observed.