Relationships between flower quality and postharvest performance: Water and sugar contents in floral organs in spray type of cut carnation flower

Abstract

Cut flowers of the spray type carnation 'Light Pink Barbara' graded as: High(H), middle(M) and the low(L) in a flower market were investigated with respect to their vase life, fresh weight, and water and sugar contents in the floral organs. 1. Total fresh weight, percent water content and water absorption were highest in H and lowest in L throughout the experiment. 2. Buds of H and M opened normally within 10 days, whereas those of L blasted; vase life in H and L were 15 and 10 days, respectively. 3. Petals of H and M contained 11 to 13 mg/100mg dry weight (DW) of glucose and fructose, respectively, at the beginning of the experiment; the concentration in H decreased to about 8 mg/100g DW within four days and sustained this level, whereas in M, they decreased to about 4 and 6 mg/100g DW by the end of the experiment. Petals of L contained 4 and 6 mg/100g of glucose and fructose, respectively, throughout the experiment. 4. Sucrose contents of leaves were 10 mg/100mg in H, 12 mg/100mg in M and about 2 mg/100mg in L; fructose and glucose contents were about 1 mg/100mg in the grades. These levels persisted throughout the experiment in leaves of all grades. 5. Sucrose contents in stem of the three grades ranged between 4 to 6 mg/100mg DW throughout the experiment; glucose content decreased from 2 mg to 0.5 mg/100mg during the same period. 6. When cut flowers were treated with silver thiosulphate, a substantial amount of silver was detected in petals, indicating that a significant uptake of the solution occurred. These results indicate the high water content percent of the cut flower with high fructose and glucose contents in the petals contribute to long vase life in spray carnation treated with silver.