Effect of different irrigation regimes and salicylic acid on morphophysiological characters of Calendula officinalis L. under zanjan climate conditions

In order to evaluatethe effect of salicylic acid on some morpho physiological charactristics of Calendula officinalis.L. under water deficit stress, an experiment was set out in split plot design based on RCBD with three replications under Zanjan climate conditions. Treatments consisted of 3 different irrigation regimes(100, 66, 33% ETC) as main plot and SA at 4 levels (0, 0.5, 1, 1.5 mM) as sub plots. Results indicated that, water deficit stress significantly increased proline content and peroxidase enzyme activity and reduced height, fresh and dry weights of shoot, flower number, flower vase life and leaf relative water content (RWC). Foliar application of SA at the 1 mM significantly increased fresh and dry weight of shoot, flower number, flower vase life, relative water content (RWC), peroxidase enzyme activity and proline content under water deficit stress. According to the results of this research, foliar application of salicylic acid could improve plant response in most traits at 1% level to drought stress.