Oligogalacturonides (OGs) are fragments of pectin released from the plant cell wall during insect or pathogen attack. They can be perceived by the plant as damage signals, triggering local and systemic defence responses. Here, we analyse the dynamics of local and systemic responses to OG perception in tomato roots or shoots, exploring their impact across the plant and their relevance in pathogen resistance. Targeted and untargeted metabolomics and gene expression analysis in plants treated with purified OGs revealed that local responses were transient, while distal responses were stronger and more sustained. Remarkably, changes were more conspicuous in roots, even upon foliar application of the OGs. The treatments differentially activated the synthesis of defence‐related hormones and secondary metabolites including flavonoids, alkaloids and lignans, some of them exclusively synthetized in roots. Finally, the biological relevance of the systemic defence responses activated upon OG perception was confirmed, as the treatment induced systemic resistance to Botrytis cinerea. Overall, this study shows the differential regulation of tomato defences upon OGs perception in roots and shoots and reveals the key role of roots in the coordination of the plant responses to damage sensing.

中文翻译：

---

根驱动寡聚半乳糖苷诱导的番茄全身免疫

寡半乳糖苷（OG）是在昆虫或病原体侵袭期间从植物细胞壁释放的果胶片段。植物可以将它们视为破坏信号，从而触发局部和系统防御反应。在这里，我们分析了番茄根或芽中对OG感知的局部和系统反应的动力学，探讨了它们对整个植物的影响以及它们与病原体抗性的相关性。用纯化的OGs处理过的植物中的靶向和非靶向代谢组学和基因表达分析表明，局部反应是短暂的，而远端反应则更强且更持久。值得注意的是，即使在叶面施用OG时，根部的变化也更为明显。这些处理差异地激活了防御相关激素和包括黄酮类在内的次级代谢产物的合成，生物碱和木脂素，其中一些仅在根部合成。最后，确认了OG感知激活的全身防御反应的生物学相关性，因为该治疗诱导了对灰葡萄孢。总体而言，这项研究显示了番茄防御对根和芽中OG的感知的差异调节，并揭示了根在协调植物对伤害感测的反应中的关键作用。