Phenotypic, bioactive and enzymatic effects of salt and gibberellic acid on some lentil cultivars

Lentil (Lens culinaris Medik.) is an important edible legume widely cultivated worldwide. Salt stress adversely affects plant growth and development, leading to yield losses. In this study, the effects of salt stress (150 mM) on phenotypic parameters were first examined in twelve lentil cultivars. Subsequently, the effects of different GA3 doses (control, 50 μM, 100 μM, and 200 μM) on the bioactive and enzymatic properties of lentil were investigated under varying levels of salt stress (control, 75 mM, and 150 mM) in the most salt-sensitive lentil cultivar. Significant reductions in root and shoot weight, root and shoot length, and leaf color parameters were observed under salt stress. Application of different doses of GA3 to the lentil cultivar grown under salt stress increased chlorophyll content, total carotenoid content, total phenolic content, total flavonoid content, total soluble protein content, and antioxidant capacity (FRAP, DPPH, CUPRAC) compared to the control group. Enzyme activity analyses revealed that GA₃ treatments enhanced catalase (CAT) and ascorbate peroxidase (APX) activities, playing a crucial role in the plant's defense mechanisms against salt stress. Principal component analysis (PCA) revealed the relationships between the studied variables and the main sources of variation in the data. The findings demonstrated that GA3 applications contribute to the improvement of stress tolerance by regulating biological and biochemical responses in salt-sensitive lentil cultivars. The results are expected to provide significant insights into breeding programs for developing salt-tolerant lentil cultivars and enhancing the bioactive and biochemical content of lentils.