EFFECT OF PRE- AND POSTHARVEST TREATMENTS ON FLOWER LONGEVITY OF CUT ROSE CV. ‘GRAND PRIX

Roses (Rosa hybrida L.) are one of the most important speciality cut flowers produced. The present experiment focuses on the effects of pre and postharvest treatments on postharvest longevity and other related characters of ‘Grand Prix’ cut roses. The results emphasized that the individual treatments with either Ca or NAA at preharvest + either Florissant-400 or silicon at postharvest significantly prolonged vase life, increased the percentage of flower opening and water uptake of rose cut flowers. Moreover, the combined treatments of Ca +NAA at preharvest +Florissant- 400 had a superior effect on extending life of flowers, increasing flower diameter (cm) and flowers fresh weight percentage. The treatment of control at preharvest plus Florissant-400 or silicon at postharvest gave the highest percentage of bent-neck at 9 days with values higher than 86%, whereas the combination between Ca+ NAA at preharvest + either Florissant-400 or silicon at postharvest recorded the highest delay for bending symptoms. Preharvest application of Ca+ NAA + either Florissant-400 or silicon at postharvest had the highest effect on reducing the depletion of sugars content and increasing anthocyanin content in flowers. The individual treatments with NAA at preharvest + either Florissant-400 or silicon at postharvesoccupied the second rank in its effect on the studied characters, thus keeping the quality of flowers compared to the other used treatments and control