Mitigation of salt stress in Camelina sativa by epibrassinolide and salicylic acid treatments

Salinity stress is a critical abiotic factor that severely limits the growth of crops and agricultural productivity. This study explores the potential of exogenously applied salicylic acid (SA) and 24-epibrassinolide (EbR) to mitigate the adverse effects of salt stress on camelina by enhancing physiological processes critical for plant resilience, such as water retention, membrane stability, and pigment biosynthesis. This research was conducted to determine the effects of two hormones applied under salt stress on the growth and development of the camelina plant (Camelina sativa) under greenhouse conditions. Eight parameters were evaluated in this study, including Fresh Weight (FW), Dry Weight (DW), Plant Water Content (PWC), Relative Water Content (RWC), Membrane Permeability (MP), Chlorophyll-a (Ch-a), Chlorophyll-b (Ch-b) and carotenoids. The results revealed that salt stress significantly reduced plant growth and productivity of all genotypes in most parameters. Under salt stress conditions, the addition of SA and the combination of EbR + SA enhanced the performance of both RWC and carotenoid parameters. In contrast, EbR treatment specifically enhanced RWC without significantly affecting carotenoid levels. The highest FW (5.49 g) and DW (1.31 g) were obtained for the NaCl + EbR + SA treatment group after the control group. The highest values of MP were obtained for the NaCl treatment group in Arslanbey genotype and for the NaCl + EbR + SA treatment group for the other two genotypes. Furthermore, when the control and NaCl + EbR + SA treatments were compared, the highest increase in Ch-a, Ch-b and carotenoid contents was obtained in PI-650142 genotype. However, more research is required to fully understand the mechanisms and effects of these compounds when applied together. Overall, SA and EbR have promising potential for improving the productivity of crops grown under salt-stress conditions. Further studies should be performed by considering the sensitivity of genotypes with low salt tolerance.