Salicylic acid and herbal extracts prolong vase life and improve quality of carnation (Dianthus caryophyllus L.) flowers

Abstract

• Exposure to 50 and 100 mg L − 1 SA resulted in marked increased in vase life of carnation flower. • The bacterial population in flowers exposed to 150 mgL −1 SA vase solution was 83% lower than that of control. • SA treated flowers displayed a dramatic increase in protein, CAT and POD activities compare to untreated control. • Salix and Mentha leaf extracts and SA enhanced the expression of CAT and POD genes, with SA treatment being most superior. The natural limitation of the cut carnation ( Dianthus caryophyllus L.) flower vase-life, led to complications in marketing and long-distance transportation. Different chemical preservatives and growth regulators are currently in use to extend the shelf and postharvest life of cut flowers. This research was aimed to evaluate the impacts of Salix and Mentha leaf extracts (SE and ME) and salicylic acid (SA) on post-harvest quality and vase life status of cut carnations flowers. Cut carnations were exposed to the various concentrations of SE and ME (25, 50 and 100 mg L − 1 ) and SA (50, 100 and 150 mg L − 1 ) vase solutions. All concentrations of SE, ME and SA considerably prolonged the vase life and increased membrane stability index (MSI), protein and antioxidant enzyme activity of catalase (CAT) and peroxidase (POD). Exposure to 50 and 100 mg L − 1 SA resulted in marked increase in vase life. In flowers treated with 150 mgL −1 SA vase solution, the bacterial population was 83% lower than control. The SA treated flowers displayed a dramatic increase in protein, CAT and POD activities compared to untreated control. Furthermore, ME, SE and SA treatments enhanced the expression of CAT and POD genes, but this increase was much greater with SA treatment. In general, post-harvest application of SA in comparison with ME and SE and control improved longevity in cut carnation flowers by enhancing the scavenging ability related to CAT and POD activity and improving the water balance.