**3.10 Strigolactones (SLs)**

Synthesized in several plant species, strigolactones (SLs) are multifunctional β-carotene derivative molecules and are considered as an essential plant hormone in regulating plant functions. SLs have been considered an emerging growth regulator for developing resilience in plants [37, 41, 179]. In salinity-treated rapeseed (*Brassica napus*), the supplied SL increased plant growth, photosynthetic traits, and antioxidant enzyme activity [180]. Involvement of SL signal transduction and SL-biosynthetic mutants in *more axillary growth3 (max3)* and *max4* was reported in SLs-mediated positive regulation of plant salt tolerance [181, 182]. In many instances, SL-mediated plant salt tolerance involved ABA accumulation [40, 183, 184]. In some studies on salinity-exposed plants, exogenous SLs improved ROS metabolism and decreased lipid peroxidation and cellular damage [185, 186]. The role of arbuscular mycorrhizal fungi and ABA in SL-assisted improvement in plant-salinity tolerance has also been reported [183, 184].
