Ascorbic and silicic acid application mitigated toxic effects of ozone in mung bean (Vigna radiata L. Wilczek) by modulating growth, secondary metabolites, water relations, and grain quality attributes.

Abstract

Background: Elevated levels of tropospheric ozone (O₃) pose a significant threat to plant health and productivity. Developing ozone-tolerant varieties is crucial for mitigating these environmental stresses. This study investigates the effects of ascorbic acid (AA) and silicic acid (SA) treatments on 12 different mung bean varieties under elevated O₃ conditions.

Results: A controlled pot experiment was conducted with four treatments: ambient O₃ (40-45 ppb), elevated O₃ (120 ppb), elevated O₃ with silicic acid (0.1 mmol L^-1), and high O₃ with ascorbic acid (10 mmol L^-1). High O₃ stress negatively impacted growth attributes across all mung bean cultivars. However, both AA and SA treatments significantly alleviated O₃-induced growth reductions. Under O₃ stress, osmotic potential, water potential, relative water content, turgor potential, sugars, pod number, amino acids, 100-seed weight, and grain carbohydrates all decreased. In contrast, antioxidant enzymes (ascorbate peroxidase, peroxidase, catalase, and superoxide dismutase), flavonoids, tannins, and grain protein content increased.

Conclusion: The NIAB Mung 20-21, NIAB Mung 2006, and NIAB Mung varieties exhibited O₃ resistance. Silicic acid proved to be more effective than ascorbic acid in mitigating O₃ damage, though a combination of both treatments was the most beneficial for enhancing plant resilience under elevated O₃ conditions. © 2025 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.