低温冷害严重影响小麦生长发育和产量形成，针对粒数形成期的低温效应研究对于高产稳产具有十分重要的意义。国内外针对小麦苗期和拔节期的低温胁迫研究较多，且偏重于形态学、生理或分子响应等某一个方面，而在多水平下对孕穗至开花期的低温耐性机制研究相对不足。我们前期持续多年的自然环境和人工气候室研究发现，西南麦区突破性小麦品种“川麦104”具有很强的低温耐性，但其生理及分子基础不明。本项目以生育进程基本一致的两个品种川麦104（耐低温）和川麦42（不耐低温）为研究对象，通过人工气候室模拟关键生育时期（孕穗、抽穗和开花）的低温胁迫及自然低温逆境，采用形态学和细胞学观察，生理生化特性检测，以及转录组、蛋白质组和代谢组学分析等方法，系统研究不同低温耐性品种在孕穗至开花期受低温胁迫后的响应机理，明确川麦104低温耐性的生理及分子基础。本项目的实施有利于丰富和完善小麦抗逆生理理论，在生产实践上指导栽培管理。

Low temperature damage seriously affects the growth, development and yield of wheat. It is significant for keeping high and stable yield of wheat to carry out research on the effect of low temperature during grain number formation period. There are many studies on the low temperature stress at seedling or jointing stage of wheat from all over the world, while most of them are focus on the morphological changes, physiological or molecular responses separately. Very few researches have been done on the mechanisms of cold tolerance during booting-flowering stage at multiple levels. After several consecutive years’ investigation in natural environment and artificial climate chamber, we observed that the outstanding wheat variety ‘Chuanmai 104’ in southwest China showed strong cold tolerance. However, the physiological and molecular basis is still unclear. In this study, two varieties with nearly consistent growth process but very different cold tolerance (cold-tolerant variety Chuanmai 104 and cold-sensitive variety Chuanmai 42) were selected as the research objects. We will use morphology and cytology observation, physiological and biochemical characteristics detection, transcriptome, proteomics and metabonomics analysis to systematic figure out the response mechanism of different wheat varieties under low temperature stress in artificial climate chamber and natural environment at critical growth stages (booting, heading, and flowering). Furthermore, we want to confirm the physiological and molecular basis of cold tolerance in Chuanmai 104. The implementation of this project is beneficial for enriching and improving the physiological theory of wheat stress tolerance, guiding cultivation management in production practice and reducing the yield loss caused by cold damage.