Delaying petal and leaf senescence in Yellow Star chrysanthemum using ascorbic acid

Abstract

Effect of non-enzymatic antioxidant ascorbic acid on leaf and petal senescence was studied in chrysanthemum cv. Yellow Star. The experiment was laid out in completely randomized design with eight treatments replicated thrice having three stems per replication. Spraying ascorbic acid at a concentration of 50 and/or 100 ppm significantly enhanced vase life of cut flowers accompanied by minimum change in fresh weight, higher solution uptake, no leaf wilting and also preserved maximum chlorophyll content (a, b and total chlorophyll) as compared to control. Maximum superoxide dismutase activity (10.51 units/mg protein/min) and peroxidase activity (25.54 millimol/mg protein/min) was recorded in flowers sprayed with 150 ppm ascorbic acid. Catalase activity (7.86 millimol/mg protein/min) was significant in flowers sprayed with 100 ppm ascorbic acid. Minimum H2O2 content (1.13 μmol/g) was observed in flowers sprayed with 50 ppm ascorbic acid as compared to control. Thus, rise in the level of superoxide dismutase, catalase, peroxidase antioxidant enzymes was observed which indicated quenching of hydrogen peroxide released by the chrysanthemum petals thus delaying leaf and petal senescence.