干旱锻炼提高小麦对灌浆期干旱耐性形成的生理机制

灌浆期干旱严重制约小麦籽粒增重，导致产量大幅波动。生育前期适宜的胁迫锻炼，可诱发产量形成关键时期小麦植株对逆境的抗/耐性，实现抗逆稳产，但其内在机制尚不明确。本项目拟在小麦生育前期进行干旱锻炼，通过灌浆期干旱胁迫下籽粒产量、植株形态及生理指标等的表现，筛选出对灌浆期干旱耐性诱导效果较好的锻炼处理；通过锻炼和未锻炼植株在灌浆期逆境下信号传导、叶片光合特性、植株糖氮代谢、细胞抗氧化系统等的表现，阐明干旱锻炼诱导耐旱性形成的生理生化机制。同时，在转录组和蛋白质水平上，研究锻炼与未锻炼植株在灌浆期干旱逆境下的差异表达基因和蛋白，结合生理生化过程研究结果，明确小麦耐旱性获得中的关键代谢途径（或位点），阐明干旱锻炼诱导耐旱性形成的内在机制。

Drought during the grain filling stage causes significant yield loss in wheat. Priming, by exposing plants to moderate stress in the early growth stage, can induce plant resistance to a later severe stress episode which happened during critical stage of the yield formation. However, the underlying mechanisms remain largely elusive. Towards this target, wheat plants will firstly be primed with a short-period moderate water deficit at different growth stages before anthesis, and then subjected to a severe drought stress during grain filling. According to the performances of grain yield, plant morphological and a variety of physiological traits, the optimum priming period will be determined. Then, we will compare the differences in signaling pathway, leaf photosynthesis, carbohydrate and nitrogen metabolism and the antioxidant system, to reveal the physiological mechanisms underlying the priming effects. Finally, both transcriptome and proteome approaches will be used to screen the differential expressed genes and proteins between the primed plants and non-primed plants under drought during grain filling. The molecular mechanisms of drought priming effects will then be elucidated.