Cucumber (Cucumis sativus L.) is one of the most widely consumed fruit vegetables throughout the world. In the present study, the effects of different concentrations of salicylic acid (0.00, 0.001, 0.01, 0.10, and 1.00mM) and two methods of its application (foliar spraying or seed priming) were investigated on morphological and physiological traits of greenhouse cucumber cv. Dream. The application methods were one-time foliar application in four-leaf stage of seedlings and seed priming in salicylic acid solutions for 24h. Results showed that the highest values for stem length, number of branches, number of leaves, number of fruits per plant, fruit diameter, fresh and dry weight of stems, and dry weight of leaves and fruits were obtained in seeds priming of 0.01mM salicylic acid and other measured traits were also improved compared with control. In addition, the prevalence of disease was not observed in 0.01mM salicylic acid. Furthermore, in treatment of 0.01mM salicylic acid, stem diameter and stem fresh weight showed a significant increase compared with control. The highest fresh and dry weight and root volume were obtained by foliar application of 0.01mM salicylic acid. The highest percentage of potassium and phosphorus in leaf samples were observed by foliar application of 0.10 and 1.00mM salicylic acid. Thus, the best values for the measured traits were observed by seed priming with 0.01mM salicylic acid.
