Effect of Silicon and Melatonin Co-application on the Physiological and Biochemical Responses of Cyamopsis Tetragonoloba L. Under Salinity Conditions

Salt stress is considered a multidimensional stress that can influence the quality and quantity of crop production. Different approaches have been attempted to reduce the negative impacts of salt stress on crops. Among various strategies applied, the use of growth-promoting agents such as silicon and melatonin has demonstrated notable effectiveness. In light of the desirable roles of silicon or melatonin on the alleviation of the possible detrimental effects related to salt stress and enhancing the morphological, physiological, and biochemical attributes, the objective of this work was to assess the roles of the combination of silicon and melatonin, and salinity on the profile of fatty acids and nutritional attributes of C. tetragonoloba L. using a 4 x 3 factorial design. The work aimed to determine the effects of Plant growth-promoting substances (PGPS) and Salinity on physiological and biochemical traits, profile of fatty acids, and nutritional attributes of C. tetragonoloba L. The results showed that salt stress caused a significant decrease in Fv'/Fm', Phi PSII, Rfd and unsaturated fatty acids, and led to an increase in malondialdehyde and saturated fatty acids. Regarding the protective impacts of combining silicon and melatonin, the salinity's adverse impacts were reduced through the foliar usage of this treatment, by improving Fv'/Fm', Phi PSII, Rfd, relative water content, potassium, magnesium, and calcium concentrations, as well as total phenolic and flavonoid contents. Therefore, the combination of silicon and melatonin improves linoleic acid, oleic acid, linolenic acid, and nutritional indices under conditions related to salt stress. Overall, silicon and melatonin's foliar combination could be an innovative approach to reduce the negative impacts of salt stress on crops.