Effect of gibberellin A(3) on leaf yellowing and vase life of cut Narcissus tazetta var. chinensis flowers

Effect of gibberellin A(3) (GA(3)) on the leaf yellowing and vase life of c ut flowers of Narcissus tazetta var, chinensis was examined. Chlorophyll co ntents of the leaves in the cut spikes or cut leaves were measured with a S PAD meter or spectrophotometer. Continuous and pulse treatments (20 hr) of the cut leaves with GA(3), especially at 100 mu M, delayed the degradation of chlorophyll. In cut spikes, the yellowing of leaves was delayed by the t reatment with GA(3) at 12 degrees C and 23 degrees C, but the effect was gr eater at 12 degrees C. Both continuous and pulse treatments extended the va se life of the flowers at 23 degrees C, but only continuous treatment did s o at 12 degrees C. The treatment with GA(3) did not promote the elongation of cut leaves and peduncles. In conclusion, the treatment with GA(3) will b e useful for improving the vase life of cut N. tazetta var. chinensis flowe rs.