Nipponbare rice was selected as the research object, and the whole process of rice seedlings from normal growth to low temperature to recovery was simulated. In combination with the determination of physiological and biochemical indicators of rice seedlings, it was found that the application of alginic oligosaccharides not only improved the ability of rice seedlings to resist low temperature stress, but also improved root vitality and the activities of SOD, POD, CAT. At the same time, when rice seedlings are subjected to low temperature stress, alginate oligosaccharides could promote the production of soluble sugars and effectively inhibit the increase of malon-dialdehyde content in rice seedlings. Label-free quantification was used to identify and analyze differential proteins and metabolites and study their metabolic pathways. After GO annotation of differentially expressed proteins, the experimental group enriched more entries. The first 10 key pathways were obtained by KEGG enrichment. Metabolomic analysis of rice seedlings by UPLC-Q-TOF-MS showed that the main small molecule differential metabolites were amines, followed by carboxylic acids and alkaloids. Through multiomics analysis, the mechanism of alginate oligosaccharides in improving the cold resistance of rice seedlings was elucidated, which provided a scientific basis for understanding the defense mechanism of cold resistance of rice seedlings as well as the development and utilization of alginate oligosaccharides.

rice seedlings, alginate oligosaccharides, cold resistance performance, proteomics, metabolomics

选取日本晴水稻作为研究对象, 模拟水稻幼苗从正常生长到遭遇低温再到复性的全过程, 结合水稻幼苗生理生化指标的测定结果, 发现施加褐藻胶寡糖不仅提高水稻幼苗抵御低温胁迫的能力, 还提高其SOD, POD和CAT活性以及根系活力; 同时, 在水稻幼苗受到低温胁迫时, 褐藻胶寡糖能促进其产生更多的可溶性糖, 并有效地抑制丙二醛含量的增加。采用非标记定量技术, 对差异蛋白和差异代谢物进行鉴定和分析, 并研究其代谢通路。差异表达蛋白进行 GO注释后, 实验组富集到的条目更多; 通过KEGG富集得到前10条关键性通路。通过UPLC-Q-TOF-MS对水稻幼苗进行代谢组学分析, 发现小分子差异代谢物主要为胺类, 其次为羧酸和生物碱等。研究结果阐明褐藻胶寡糖提高水稻幼苗抗寒性能的机理, 可为理解水稻幼苗抗寒性能防御机制及褐藻胶寡糖的研发利用提供科学依据。

水稻幼苗, 褐藻胶寡糖, 抗寒性能, 蛋白质组学, 代谢组学