水稻低温胁迫不同时间的代谢物谱图分析

苗期低温严重影响水稻幼苗生长, 分析低温胁迫下幼苗体内代谢物变化特征有助于解析水稻应对胁迫的生理机制。采用气质谱联用仪(GC-MS)技术系统分析水稻品种IR64遭遇不同时间段低温后代谢物图谱的变化特征。结果表明, 草酸、戊糖酸-1,4-内酯、海藻糖及水杨酸参与了水稻低温胁迫早期应激性反应; 在低温胁迫过程中, 水稻植株主要通过苯丙氨酸、脯氨酸、谷氨酸、丝氨酸、苏氨酸、天门冬氨酸、缬氨酸、木糖醇、尿囊素和鼠李糖等含量的提高维持细胞渗透平衡。代谢物动态分析发现参与低温胁迫反应及胁迫恢复后进程的主要代谢物不同。研究结果为全面系统剖析水稻耐冷胁迫的分子生理机制打下了基础。

Time-Course Metabolic Profiling in Rice under Low Temperature Treatment

Rice seedling growth is inhibited greatly by the occurrence of low temperature. Characterization of the dynamic changes in rice metabolite under chilling stress will contribute to the understanding of physiological mechanism responsive to abiotic stresses. At the present study, the time-course metabolic profiling of the rice variety, IR64, under low temperature was investigated with GC-MS technique. The results showed that the contents of the oxalic acid, pentonic acid-1,4-lactone, trehalose and salicylic acid increased greatly at the early chilling stress, while phenylalanine, proline, glutamicate, serine, threonine, asparticate, valine, xylitol, allantoin, and rhamnose were induced significantly by the low temperature treatment to keep the osmotic homeostasis. Further dynamic analysis of metabolites indicated that different sets of metabolites were involved in the chilling stress response and the subsequent recovery process. All these results provide a basis for further elucidation of molecular physiological mechanism in rice chilling tolerance.