The impact of pre-harvest treatment with gamma-aminobutyric acid (GABA) and salicylic acid on vase life and post-harvest traits of tuberose cut flowers

Abstract

Tuberose (Polianthes tuberosa L.) is an ornamental bulbous plant and a famous cut flower in tropical and subtropical regions. Post-harvest senescence of the cut flowers is the main factor limiting the marketability of most of these species including tuberose. From the perspective of metabolic changes, senescence happens as the result of oxidative processes induced by active oxygen species production. Gamma-aminobutyric acid (GABA) and salicylic acid (SA) are compounds with some functions in the post-harvest physiology of some plants. The present study focused on the effect of GABA and SA on vase life and some post-harvest traits of cut tuberose flowers. The plants were sprayed with GABA (5, 10, or 15 mg L–1) and SA (50, 100, or 150 mg L–1) at three stages during growth and before harvest in a greenhouse (30, 45, and 60 days after the planting of the bulbs) and were observed after harvest until senescence. Results showed that GABA and SA positively affected the vase life, water uptake, fresh weight, ion leakage, total dissolved solids, chlorophyll, protein, and catalase, peroxidase, and ascorbate peroxidase enzymatic activity. They postponed senescence. The highest and lowest vase lives were observed in plants treated with 10 mg L–1 GABA (11 days) and control (distilled water) (7 days), respectively. It was found that the treatment of tuberose with GABA and SA during growth can improve its post-harvest quality. However, it is recommended to conduct further studies on them.