The study was conducted at the Postharvest Lab. of Floriculture Res. Dept., Hort. Res. Inst., Giza, Egypt during 2012 and 2013 seasons to explore the effect of silver thiosulphate solution (STS) applied as foliar spray or as immersing solution for 10, 20 and 30 minutes (control spikes were immersed in distilled water), cold storage at 5 °C, vertically or horizontally for 2 or 4 days, beside control treatment in which spikes were kept at room temperature and their interactions on water relations, longevity and quality of Gladiolus hybridus cv. "White Prosperity" cut spikes. After each treatment, the bases of spike stems were held in 10 % sucrose solution till the end of the experiment.
The obtained results showed that STS pulsing treatments caused a significant increment in the amount of water uptaken by cut Gladiolus spikes, and significantly decreased, the amount of water loss compared to control in most cases of the two seasons. These treatments were also improved floret diameter, vase life, spike fresh and dry weights, dry weight %, opening %, leaf content of chlorophyll a, b and reducing sugars % in the leaves petals, and decreased wilting %, and carotenoids content in the leaves and total sugars % in the leaves and petals. However, the prevalence was for immersing in STS solution for 10 min treatment, which gave the best values in most previous characters with few exceptions in both seasons. Storage at room temperature or at 5°C, vertically or horizontally for 2 or 4 days alternated improving means of previous characters with the mastery of horizontal cold storage treatment for 2 days, which recorded the best results in most cases. The interaction treatments also induced a marked improvement in most measurements, but the dominance was for the combining between immersing in STS solution for 10 min. and horizontal cold storage for 2 days, as this combination gave the best water relations, the longest vase life and the highest quality compared to the other individual and combined treatments.
Accordingly, it is recommended to immerse the cut spikes of Gladiolus cv. "White Prosperity" in STS solution for 10 min and then holding them in 10 % sucrose solution at room temperature for local marketing or storage them after immersing in STS solution, horizontally for at least 2 days at 5 °C for shipment abroad.