Anatomical and physiological traits of broad bean (Vicia faba L.) seedling affected by salicylic acid and salt stress

A laboratory experiment was carried out at the College of Agriculture University of Baghdad in 2017. The aim was to improve the anatomical and physiological traits of broad bean seedling under salt stress by soaking it in salicylic acid. The concentrations of salicylic acid were 0, 10, and 20 mg L⁻¹ and the electrical conductivity levels were 0, 3, and 6 dS m⁻¹. The complete randomized design was used with four replications. The increasing of salicylic acid concentration up to 10 mg L⁻¹ led to increasing the stem cortex thickness, stem vascular bundles thickness, and root cortex thickness significantly by (34.9, 36.7, and 55 μm) respectively, while the treatment of 20 mg L⁻¹ led to decreasing these traits by (28.2, 27.8, and 48.1 μm), compared to control treatment (33.8, 35.9, and 53.8 μm), respectively, and the interaction of studied factors led to increasing those traits up to 10 mg L⁻¹ and then decreased up to 20 mg L⁻¹ of salicylic acid under each level of electrical conductivity. Therefore, it is recommended to soak the broad been seeds with 10 mg L⁻¹ salicylic acid to improve the anatomical traits of seedlings and increase their tolerance to salt stress up to 6 dS m⁻¹.