Enhancing the nutritional value of sweet bell pepper through moderate NaCl salinity

Salinity presents a significant obstacle to crop productivity, particularly in dry and semi-arid regions. Sweet bell pepper (Capsicum annuum L.), a widely grown and consumed horticultural crop, is especially vulnerable to salinity. Consequently, it is vital to determine the salinity threshold that impacts bell pepper growth and quality, enabling sustainable production in salinized areas. This study aimed to evaluate the effects of varying sodium chloride concentrations (0, 50, and 75 mM) on bell pepper growth, nutritional value, and phytochemical composition, aiming to identify the adaptable threshold in salinized environments. The results suggested that the application of 75 mM NaCl not only had no adverse impact on fruit quality in terms of biomolecules and phytochemicals but also led to significant improvements. Specifically, under these conditions, there was a remarkable increase, in respect to control, in total protein (TPRO by 50 %), total carbohydrates (TCARB by 18 %), lycopene (LIC by 68 %), total Carotenoids (TCAR by 13 %), and total phenols (TPHE by 18 %) in terms of antioxidants.In contrast, the content of ascorbic acid and antioxidant activities remained consistent. Moderate salt stress exhibited the most positive influence on sweet bell pepper quality, leading to higher concentrations of essential nutrients and nutraceutical compounds, including minerals, phenolic acids, and flavonoids.