Effect of salicylic acid on some physiological indices of Chrysanthemum cv “mai vang” cut flowers

Chrysanthemum (Chrysanthemum sp.) has an important economic and medicinal value. This plant is the second most important cut flower produced in the world. Salicylic acid is a growth regulator with multifunction that is involved in plant physiology. In this works, the effect of salicylic acid at different concentrations (0.0; 0.25; 0.5; 0.75; 1.0; 1.5 and 2.0 mM, respectively) on physiological characteristics of Chrysanthemum "mai vang" cut flowers was investigated. Research results indicated that salicylic acid affected the content of photosynthetic pigments and chlorophyll fluorescence of leaves as well as anthocyanin content in the petals Chrysanthemum cv. “mai vang” cut flowers. Salicylic acid at concentrations of 0.25 - 0.5 mM increases the content of chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids in leaf tissue at days 2 to 5 compared to day 1. The content of these photosynthetic pigments did not change through the experiments under influence of 0.75-1.0 mM salicylic acid. Meanwhile, salicylic acid at the concentration of 1.5 - 2.0 mM reduced photosynthetic pigment content at days 3 - 5 compared to day 1. A decrease of Fv\Fm value from day 1 to day 5 was observed in all experimental formula, the smallest reduction was found in the 0.25 and 0.5 mM treatments. Anthocyanins were higher accumulated in Chrysanthemum "mai vang" petals in all experimental formulas at days 2 to 4 than at day 1. At day 5, the anthocyanin content was still higher than at day 1 under salicylic acid treatments with concentrations of 0.25 - 0.75 mM.