Effect of salicylic acid and brassinosteroid on physiological response and grain and oil yield of coriander (Coriandrum sativum L.) under water deficit

A field experiment was carried out as a split-plot based on a randomized complete block design with three replications in 2020, to evaluate physiological performance and grain and oil yield of coriander, in response to water limitation and foliar application of salicylic acid and brassinosteroid. Treatments were four levels of water supply (irrigation after 70, 100, 130 and 160 mm evaporation from class A pan) and three levels of foliar application (control (foliar application of water), foliar application of salicylic acid (1 mmolar) and foliar application of brassinosteroid (1 μmolar). Irrigation and foliar application treatments were allocated to main and subplots, respectively. In this study, proline content, leaf chlorophylls a and b and carotenoids content, antioxidant enzymes activity, soluble sugars and anthocyanin content and oil percentage and yield of coriander were evaluated. Water deficit stress resulted in a 20.6% and 21.6% decrease in chlorophylls a and b content, respectively and a 62.9% increase in leaf carotenoids. However, leaf proline content increased under water deficit stress. The mean leaf chlorophyll a content increased significantly (11.4%) compared to the control with salicylic acid