Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing 210037, China.
Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing 210037, China.
Int J Mol Sci. 2022 Aug 30;23(17):9854. doi: 10.3390/ijms23179854.
Iron deficiency causes chlorosis and growth inhibition in , an important landscaping tree species. Siderophores produced by plant growth-promoting rhizobacteria have been widely reported to play an indispensable role in plant iron nutrition. However, little to date has been determined about how microbial siderophores promote plant iron absorption. In this study, multidisciplinary approaches, including physiological, biochemical and transcriptome methods, were used to investigate the role of deferoxamine (DFO) in regulating Fe availability in seedlings. Our results showed that DFO supplementation significantly increased the Fe content, SPAD value and ferric-chelate reductase (FCR) activity in plants, suggesting its beneficial effect under Fe deficiency. This DFO-driven amelioration of Fe deficiency was further supported by the improvement of photosynthesis. Intriguingly, DFO treatment activated the metabolic pathway of glutathione (GSH) synthesis, and exogenous spraying reduced glutathione and also alleviated chlorosis in . In addition, the expression of some Fe acquisition and transport-related genes, including , , , and , was significantly upregulated by DFO treatment. Collectively, our data demonstrated an effective, economical and feasible organic iron-complexing agent for iron-deficient camphor trees and provided new insights into the mechanism by which siderophores promote iron absorption in plants.
缺铁会导致樟树（一种重要的景观树种）出现黄化和生长抑制。植物促生根际细菌产生的铁载体已被广泛报道在植物铁营养中发挥不可或缺的作用。然而，迄今为止，关于微生物铁载体如何促进植物铁吸收的研究还很少。在这项研究中，采用了包括生理、生化和转录组学方法在内的多学科方法，研究了去铁胺（DFO）在调节樟树幼苗铁供应中的作用。研究结果表明，DFO 补充显著增加了植物中的铁含量、SPAD 值和三价铁螯合还原酶（FCR）活性，表明其在缺铁条件下具有有益作用。DFO 驱动的缺铁缓解作用进一步得到了光合作用改善的支持。有趣的是，DFO 处理激活了谷胱甘肽（GSH）合成的代谢途径，外源喷施还原型谷胱甘肽也能缓解樟树的黄化。此外，DFO 处理还显著上调了一些铁吸收和转运相关基因的表达，包括 、 、 、 和 。总之，我们的数据表明，DFO 是一种有效、经济且可行的缺铁香樟树有机铁螯合剂，为铁载体促进植物铁吸收的机制提供了新的见解。
