College of Food Science and Engineering, Ocean University of China, Qingdao, China; State Environmental Protection Key Laboratory of Estuarine and Coastal Environment Beijing, Beijing, China.
College of Food Science and Engineering, Ocean University of China, Qingdao, China.
Int J Biol Macromol. 2021 Jul 31;183:12-22. doi: 10.1016/j.ijbiomac.2021.04.121. Epub 2021 Apr 20.
Polysaccharides derived from seaweeds can be used as biostimulants to enhance plant resistance to different stressors. In this study, we investigated the effects of applying low molecular weight polysaccharides (LPU) derived from Ulva prolifera with 14.2 kDa on the responses of wheat (Triticum aestivum) to osmotic stress. The results showed that osmotic stress simulated using polyethylene glycol inhibited seedling growth, whereas we observed increases in the fresh weights and shoot lengths of seedlings treated with polysaccharide for 120 h. Furthermore, we observed enhanced activities of antioxidant enzymes, and significant reductions in malondialdehyde content of 23.13%, 19.82%, and 20.04% in response treatment for 120 h with 0.01%, 0.03%, and 0.05% LPU, respectively, relative to those in the group treated with polyethylene glycol alone. In all treatments, expression of the P5CS gene was upregulated to promote proline accumulation. Moreover, after 120 h, exogenously applied LPU induced the expression of stress-related genes, including SnRK2, Wabi5, Wrab18, and Wdhn13. Collectively, these findings indicate that LPU might have the effect of regulating the abscisic acid-dependent pathway in wheat, thereby increasing seedling antioxidant capacity and growth. Application of LPU may accordingly represent an effective approach for enhancing the resistance to osmotic stress in wheat.
海藻来源的多糖可用作生物刺激素，以增强植物对不同胁迫的抗性。在这项研究中，我们研究了用 14.2 kDa 的浒苔提取的低分子量多糖（LPU）对小麦（Triticum aestivum）对渗透胁迫响应的影响。结果表明，用聚乙二醇模拟的渗透胁迫抑制了幼苗生长，而用多糖处理 120 h 的幼苗鲜重和苗高增加。此外，我们观察到抗氧化酶活性增强，丙二醛含量分别降低了 23.13%、19.82%和 20.04%，用 0.01%、0.03%和 0.05%的 LPU 处理 120 h 后，与单独用聚乙二醇处理的组相比。在所有处理中，P5CS 基因的表达均上调以促进脯氨酸积累。此外，经过 120 h，外源施加的 LPU 诱导了与应激相关的基因的表达，包括 SnRK2、Wabi5、Wrab18 和 Wdhn13。总之，这些发现表明 LPU 可能具有调节小麦中脱落酸依赖途径的作用，从而提高幼苗的抗氧化能力和生长。因此，LPU 的应用可能代表了增强小麦抗渗透胁迫的有效方法。
