Effect of some chemical and natural preservative solutions on vase life, water relations and some chemical composition of Dianthus caryophyllus L. cut flowers

To investigate the effect of some pulsing and holding solutions on the quality of carnation cv. Turbo cut flowers, a laboratory experiment was conducted in the Agricultural Research Center and Cairo University, Egypt during 2020 and 2021 seasons. In this regard distilled water, silver thiosulfate (STS) at 0.4 ppm + sucrose 10% (PS1) and AgNO3 at 10.0 ppm + sucrose 10% (PS2) were employed as a pulsing solution for 15 min while distilled water, sucrose 4% (HS1), boric acid (BoA) at 200 ppm + sucrose 4% (HS2), 8-hydroxyquinoline sulfate (8-HQS) at 300 ppm + sucrose 4% (HS3), Amino-oxyacetic acid (AOA) at 250 ppm + sucrose 4% (HS4), 8-HQS + AOA + sucrose 4% (HS5), BoA + 8-HQS + sucrose 4% (HS6), BoA + AOA + sucrose 4% (HS7), BoA + 8-HQS + AOA + sucrose 4% (HS8), rosemary extract at 25% + sucrose 2% (HS9) and thyme extract at 25% + sucrose 2% (HS10) were used as holding solutions. Regarding pulsing solutions, PS2 and PS1 exhibited a positive effect on all studied traits, while the mastery was to HS8 concerning the effect of holding solutions. Pulsing cut carnations in a solution containing PS2 followed by holding in HS8 resulted in the highest values in terms of vase life, water balance, chlorophyll a, carotenoids and total sugars, while the highest water uptake and loss and chlorophyll b were obtained by pulsing in PS1 followed by holding in HS8. It is recommended to pulse carnation cv. Turbo cut flowers in AgNO3 at 10.0 ppm + sucrose 10% solution for 15 min followed by holding in BoA + 8-HQS + AOA + sucrose 4% for getting the longest vase life, enhancing water uptake and maintaining water balance. Additionally, this preservative solution effectively reduces chlorophyll degradation and preserves the content of carbohydrates throughout the postharvest period.