Low temperatures limit the yield and stability of autumn-sown oats; thus, investigating cold resistance physiological responses is essential. In this study, we compared a cold-resistant variety (‘Aiwo’) and a cold-sensitive variety (‘Hewang’). ‘Aiwo’ exhibited a significantly higher overwintering survival rate (96.9%) and superior physiological traits, including elevated levels of soluble proteins, proline, putrescine, unsaturated fatty acids, and glutathione, alongside greater ATPase activity and reduced ROS levels. Exogenous putrescine application suggested a potential role of Put in alleviating lipid peroxidation. Metabolomic analysis showed that the arginine–proline and cysteine–methionine pathways were enriched among DAMs associated with ‘Aiwo’, accompanied by the accumulation of stress-protective metabolites. These metabolic changes may contribute to improved energy balance and membrane stability under low-temperature conditions. Our findings suggest that proline, putrescine, and glutathione are candidate physiological indicators associated with the cold-resistant phenotype, which may facilitate future screening of cold-resistant oat germplasm.
Zhang et al. (Sun,) studied this question.