Ascorbic acid as a mitigator of salt stress effects on radish

ABSTRACT Using water with high salt concentrations in irrigated agriculture can affect sensitive plants’ metabolic and biochemical functions. Therefore, strategies are needed to minimize the adverse impacts of salt stress. This study aimed to evaluate radish plant growth, water relations, and biochemical and nutritional responses as a function of irrigation water salinity and exogenous ascorbic acid (AsA) application. The experiment was conducted in a controlled greenhouse under a completely randomized design in a 3 × 2 factorial scheme with four replicates, using one plant per experimental unit. Treatments consisted of three levels of irrigation water salinity (0.5, 3.0, and 5.0 dS m-1) and ascorbic acid application [without (0 mM) and with (1 mM)]. Increased salinity (3.0 and 5.0 dS m-1) affected growth, water status, biochemical traits, and nutrient accumulation in radish plants. Stem diameter (55.0%), shoot mass ratio (14.5%), relative growth rate (9.0%), and soluble sugars in shoot (29.8%) and root (47.6%) increased with 1 mM AsA application, especially at 5.0 dS m-1. Applying 1 mM AsA reduced Na⁺ and Cl⁻ cont 0ents in both shoot and root at all salinity levels and increased the Mg²⁺ content in shoot and root and Ca²⁺ content at 3.0 and 5.0 dS m-1.