Strigolactone‐Mediated Modulation of Physiological and Biochemical Responses Under Salinity Stress in
Punica granatum
Emad H. Khedr, Mohamed Abdel‐Haleem, Mohamed M. El‐Mogy, Hossam S. El‐Beltagi ABSTRACT
Salinity stress is a major constraint affecting pomegranate productivity and fruit quality. This study evaluated the effects of strigolactone (SL) at 15 and 30 μM on alleviating salinity stress and improving fruit yield and quality in pomegranate trees over two consecutive seasons. SL treatments significantly enhanced yield per tree, fruit weight, total soluble solids, firmness, ascorbic acid, and anthocyanin content compared with untreated trees. In addition, SL improved relative water content, indicating improved plant water status under saline conditions. SL application reduced membrane permeability and malondialdehyde content, reflecting enhanced membrane stability and reduced oxidative damage. Moreover, antioxidant enzyme activities were significantly increased following SL treatments. Elevated levels of proline and amino acids further suggest improved osmotic adjustment under salinity stress. The results also suggest that SL treatments are associated with changes in the activities of key enzymes involved in the phenylpropanoid pathway, including cinnamate 4‐hydroxylase, 4‐coumarate‐CoA ligase, cinnamyl alcohol dehydrogenase, and cinnamoyl‐CoA reductase, which may be linked to changes in anthocyanin content. Overall, these findings highlight the role of SL in modulating physiological and biochemical responses associated with salinity tolerance in pomegranate and support its potential as a biostimulant for sustainable fruit production in salinity‐affected environments.