Effect of spermidine and irrigation period on some physiological characteristics of Cucurbit (Cucurbita pepo L.)

In this study the effect of spermidine on proline, soluble sugars, peroxidase, ascorbate peroxidase, membrane stability and chlorophyll a and b, under irrigation period were evaluated. This study was conducted in pots and as a factorial completely randomized design in four replications. Espermidine was applied at 0, 1 and 2 mM and irrigation period was imposed at three days, five days and seven days in between. The Results showed irrigation period in seven days compared to control group increases proline content, activity of peroxidase and ascorbate peroxidase and membrane stability, and decrease in soluble sugars, chlorophyll a and b. The plants that have been irrigated for seven days, treatment with 2mM spermidine (relative to concentrations of 0 and 1 mM) increased proline content, soluble sugars, activity of peroxidase and ascorbate peroxidase at the highest level (class a). The membrane stability in these plants the concentration of 0 mM spermidine was highest (77.75%). Spermidine had no significant effect on chlorophyll a and b. Generally treatments with 2 mM spermidin in plants that were irrigated for seven days Increased proline content (1.11 mM/g.FW), soluble sugars (0.96 mg/gFW), peroxidase activity (0.91 OD.g-1.FW.min-1) and ascorbate peroxidase activity (0.98 OD.g-1.FW.min-1) at the highest level (class a).