Impacts of Trehalose on morphological traits and water relation parameters of Arsenic toxicity in Brassica juncea L

Arsenic (As) toxicity is a significant global issue that severely restricts crop growth and productivity. This study investigated the ameliorative effect of exogenous Trehalose (Tre), a natural sugar with well-documented osmo-protective and antioxidative functions, on B. juncea (Indian mustard), a model hyperaccumulator species known for its rapid growth. Plants were exposed to As stress (0.4 mM) and treated with Tre at concentrations of 25, 50, and 75 mM under both in vitro and pot conditions. Among the tested concentrations, 75 mM Tre was most effective in mitigating As-induced damage in 30-, 60-, and 90- days-old plants. Compared to untreated As- stressed plants, 75 mM Tre-treated plants showed marked improvements in root and shoot lengths, stomatal performance, relative water content, and mineral (K, Mg, P) uptake, along with significantly reduced As accumulation. Moderate benefits were obtained at lower concentrations (25 and 50 mM). These findings highlight that the Tre application, particularly at 75 mM, significantly reduces As toxicity in B. juncea , providing a safe and sustainable method of boosting crop resilience. Future research should focus on elucidating the molecular mechanisms underlying Tre action and validating its efficacy under field conditions across diverse crop species to support sustainable agriculture in As-contaminated environments.