Impact of Gibberellic Acid and Calcium Chloride Treatments on Neck Bending Prevention and Vase Life Extension of Gerbera Cut Flowers

Neck bending (NB) and capitulum wilting are the major issues that shorten the vase life (VL) of gerbera cut flower. In the present study, the influence of exogenous application of gibberellic acid (GA3, 1.0 mM) or calcium chloride (CaCl2, 5.0 mM) at three different pre-harvest times (one time spraying (T1): concurrent with the emergence of more than 50% of flowering shoots (15day before harvesting), two times spraying (T2): at T1 and 7day later (15 and 8day before harvesting), and three times spraying (T3): at T1 and 5 and 10day later (15, 10, and 5day before harvesting)) on extending VL of gerbera 'Stanza' cut flowers was investigated. GA3-T3 and CaCl2-T3 treatments decreased NB and extended VL of gerbera cut flowers by increasing vase solution uptake (VSU) and phenylalanine ammonia-lyase enzyme (PAL) activity, which led to increasing water content and cell wall strength (due to increasing lignin deposition). On the other hand, GA3-T3 and CaCl2-T3 treatments decreased the activity of polyphenol oxidase enzyme (PPO) (the enzyme involved in browning reaction) and the oxidative damages through enhancing phenolic compounds accumulation and antioxidant enzymes activity. Pre-harvest treatments reduced H2O2 accumulation and membrane lipid peroxidation in gerbera 'Stanza' cut flowers. The results of the current study clearly demonstrated that both GA3-T3 and CaCl2-T3 treatments could reduce NB and extend VL of 'Stanza' cut flowers, therefore could be recommended as pre-harvest treatments to maintain quality of gerbera cut flowers during storage.