Ascorbic Acid Application Improves Salinity Stress Tolerance in Wheat

Abstract

Salinization converts fertile land into infertile land, and is a severe threat to food security and crop productivity worldwide. In this study, we treated wheat plants (Triticum aestivum L. var. Yecora Rojo) with or without ascorbic acid (ASA), both under salt stress and non-stress conditions, to understand the effect of ASA on plant response to salinity stress. We monitored the amounts of photosynthetic pigments, osmoprotectants, and antioxidant enzymes. Application of ASA enhanced growth characteristics, such as shoot and root length, shoot and root fresh weight, shoot and root dry weight. It also improved the physiological and biochemical parameters, such as carbonic anhydrase (CA) and Rubisco activities, photosynthetic pigments (Chl a, b, and Total Chl), and compatible solutes (proline [Pro] and glycinebetaine [GB]) contents, under non-stress conditions. Under NaCl stress, the ASA addition improved growth attributes, levels of pigments, accumulation of Pro and GB, and antioxidant enzymes activities, such as superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase. Also, ASA decreased Chl degradation, electrolyte leakage, and concentration of malondialdehyde and hydrogen peroxide in wheat plants. We conclude that supplementing ASA can benefit wheat plants by improving their tolerance to salinity stress.