Extending vase life of carnation flowers by postharvest nano silver, humic acid and Aloe Vera gel treatments

Abstract

Standard Carnation flowers (Dianthus caryophyllus cv. Dover) were harvested at the paint brush stage in the early morning, pre-cooled at 4° C for 6-h then moved under dry conditions to the laboratory. Flowers were weighted and treated for 24-h with silver nanoparticles (AgNPs) at 0, 5 or 10 ppm in plastic buckets. After pulsing treatments, cut flowers were transferred to 500 mL glass jars containing 300 mL of preservation solution treatments including, individually, humic acid at 200, 400 or 600 ppm and Aloe vera gel at 2.5%, 5.0% or 7.5% (w/v) till the end of the experiment (when flower color began to fade, petals began to roll). Distilled water was used for the control and to prepare the tested solutions. 2% sucrose was added to all treatments including the control. Addition of all preservatives to vase solutions significantly increased all the studied characteristics of cut flowers compared to control (distilled water, least values). Nanosilver treatments have the potential to be used as preservative solutions for improving postharvest vase life and quality of carnation flowers. An increment in vase life, relative fresh weight, vase solution uptake, flower diameter as well as total chlorophylls in leaves, total carbohydrates and total phenols in leaves and petals was observed, in addition to a decrease in bacterial counts in vase solution. Best results were obtained using 5 ppm AgNPs + 5.0% Aloe vera gel followed by 5 ppm AgNPs +7.5% Aloe vera gel solutions. Aloe vera gel, especially 5.0% level, showed better results than humic acid when used alone or combined with AgNPs. Nanosilver at 5 ppm recorded better results than 10 ppm when used as a single treatment.

Response of preservative chemicals on the shelf life of cut lilium (Lilium spp.) flower cv. ‘Pavia’

“…Results showed that more than 80% of flowers were opened on 11 th day and treatment combination 50 ppm AgNO 3 and 20% sucrose (T 5 ) took maximum 12.5 days on average to open all the flowers on the spike and resulted in long vase life of the spike followed by 8 8-HQC (150 ppm) + AgNO 3 (75 ppm) + Sucrose (20%) T 13 8-HQC (200 ppm) + AgNO 3 (75 ppm) + Sucrose (20%) T 14 8-HQC (100 ppm) + AgNO 3 (100 ppm) + Sucrose (20%) T 15 8-HQC (150 ppm) + AgNO 3 (100 ppm) + Sucrose (20%) T 16 8-HQC (200 ppm) + AgNO 3 (100 ppm) + Sucrose (20%)…”