Effects of spermidine spray on morphological, physiological and biochemical characteristics of Cyclamen persicum Miller.

Persian cyclamen is a perennial geophytes plant which has a special position between ornamentals due to its charm, diversity and flowering during winter. As this flower’s quality and quantity is affected extensively by its nutrition and environmental factors, and regarding the importance and special role of poly amines in plant nutrition, this experiment was conducted to evaluate the external application of spermidine on the quality and quantity of this Iranian native flower. Therefore an experiment was conducted in two parts. In the first part, cyclamen plants were sprayed with spermidine (0, 5, 10 and 20 mM) in a completely randomized design and morphological and physiological characteristics were studied. This was while the second part was factorially arranged in a completely randomized design and cyclamen plants were treated with spermidine (0, 5, 10 and 20 mM) at five different flower development stages for studing biochemical characteristics. Studied morphological characteristics were: bud stage days, blooming days, total flowering days, total flowers, leaf area and number. Studied physiological characteristics were: fresh weight, dry weight, relative water content and membrane stability index of petals. This was while for biochemical characteristics superoxide dismutase, catalase beside protein, spermidine and spermine content were studied. Morphological results indicate the beneficial effect of external spermidine application on flowering and vegetative growth of Persian cyclamen. Effective level of spermidine application on flowering characteristics was 10 mM while for vegetative growth it was 20 mM. Besides that, spermidine application increased fresh weight, dry weight, relative water content and membrane stability index of petals. Free radical scavengers such as SOD and CAT beside protein content increased during flowering stages 1 to 5. Spermine content showed a similar increasing trend by spermidine application, while spermidine content increased during flowering phase 1-3 and decreased afterwards.