Overexpression of BdASR2 Plays a Positive Role in Response to Salt Tolerance in Brachypodium distachyon

Adverse environmental stresses are known to affect plant growth and development, thus reducing crop productivity. Abscisic acid-, stress -, and ripening-induced (ASR) proteins play important roles in protecting plants from adverse environmental conditions. However, the biological functions of ASR proteins in Brachypodium remain unclear. We characterized the Brachypodium BdASR2 gene and concluded that it plays a positive role in salt stress tolerance. Overexpressing BdASR2 plants showed enhanced salt tolerance and decreased ion leakage and MDA content as compared to WT plants under salt stress conditions. Moreover, the roots were longer in overexpressing BdASR2 plants than WT plants under salt stress. The overexpression of BdASR2 increased antioxidant enzyme activity and upregulated the expression of stress-related genes under salt stress conditions. Taken together, these results indicate that BdASR2 plays important roles in salt stress responses by controlling ROS homeostasis and regulating the expression of stress-related genes.