种子劣变是引起种子活力丧失的关键因素，也是导致种子质量下降和经济损失的直接原因。研究种子劣变的生理机制对保持种子活力和发挥其遗传潜能具有非常重要的理论价值和现实意义。试验以10%和16%含水量的燕麦种子为材料，采用45℃控制劣变处理获得不同活力水平的种子样品。通过透射电镜观测不同活力水平种子的线粒体超微结构变化；针对抗坏血酸—谷胱甘肽（AsA-GSH）循环，采用外源抗氧化剂处理分析比较抗氧化酶和代谢产物的变化规律；利用双向电泳和质谱分析以及iTRAQ技术确定线粒体差异蛋白的种类及表达水平，并结合qRT-PCR鉴定与差异蛋白表达相关的功能基因。试验目的在于研究安全含水量和高含水量种子贮藏劣变过程中，种胚线粒体的结构和功能变化规律以及抗坏血酸—谷胱甘肽循环的抗氧化机制，为探索燕麦劣变种子线粒体活性氧自由基清除的作用机理提供理论依据。

Seed deterioration is the key factor that causes the loss of seed vigor, and also is the direct reason for the economic loss of agricultural production due to declining of seed quality. There are very important theoretical value and practical meaning to study and reveal the mechanisms of seed deterioration for maintaining seed vigor and exerting genetic potential. Oat (Avena sativa) seeds with 10% and 16% moisture content were adopted in this study and aged at 45 °C to obtain samples with different vigor levels. Changes of mitochondrial ultrastructure including membrane system were observed by transmission electron microscope; for ascorbic acid-glutathione (AsA-GSH) cycle, exogenous antioxidants were used to analyze and compare the changing rules of antioxidant enzymes and metabolic products. Furthermore, the types and expression levels of mitochondrial proteins were determined by two-dimensional electrophoresis and iTRAQ; functional genes associated with expression of differential proteins were identified by qRT-PCR. The objectives were to determine the changes in ultrastructure and function of embryonic mitochondria and antioxidation mechanisms of AsA-GSH cycle during seed deterioration at safe or high moisture content, and to provide theoretical basis for exploration the scavenging mechanism of active oxygen free radicals in mitochondria.