The effect of pulsing and continuous treatments of chemical preserving solutions on increasing the vase life and quality of cut carnations (Dianthus caryophyllus L., cv.Yellow Candy)

Carnations are one of the most common cut flowers in many countries and have economic importance in the floriculture industry. Their vase life duration could be increased by some methods. The aim of this study was to assess the effect of some chemical solutions on cut carnations (Dianthus caryophyllus) after harvest using a factorial statistical design based on a completely random blocks (factor A: chemical treatments with eight levels including, control, sucrose, HQC350 & 500 mg L-1, salicylic acid 300 & 400 mg L-1, Calcium acetate 2 & 3 mmol L-1 and factor B: duration of treatment application with 4 levels including 7, 14, 21 and continuous hours) and with three replications and evaluation of vase life, fresh weight, water absorption and appearance quality of the flowers. The results of variance analysis showed that chemical treatments had a significant effect on the studied characteristics. The period for solution intake was also significant regarding the studied characteristics (except water absorption). The effect of interaction of the type of solution and time of solution intake was significant for all characteristics. The results of mean comparison showed that Calcium acetate 2ml had the highest effect on the shelf life of the flower and the 8-HQC500 had the most effect on the fresh weight of the flowers. Its apparent quality and finally the 8-HQC350 treatment had the most effect on the flower's water absorption. Salicylic acid also had a beneficial effect on increasing the quality of cut carnations. The pulsing treatment had the highest effect on most of the studied characteristics after a 7-hour solution intake. Generally, the role of Calcium acetate on improving the quality of cut carnations is due to its effect on postponing and deactivating some destructive and physiologic processes with the help of Calcium. Moreover, the HQC treatments, due to its anti-microbial effect, revents the accumulation of micro-organisms in xylem vascular tissues and therefore prevents their obstruction.