Exogenous melatonin enhances Lr10-mediated resistance to Puccinia triticina by upregulating TaRAR1 and potentiating salicylic acid pathway and antioxidant defense system

作者：Johannes Mapuranga, Lulu Song, Ruolin Li, Hao Li, Jiaying Chang, Jiaojie Zhao, Yingdan Zhang, Na Zhang, Yang WenXiang · 发表于：Plant Stress · 年份：2025 · DOI：10.1016/j.stress.2025.100974 · 被引用次数：6 · 研究领域：Plant Stress Responses and Tolerance、Plant-Microbe Interactions and Immunity、Photosynthetic Processes and Mechanisms

• Exogenous melatonin (100 µM) augments wheat resistance to Puccinia triticina through the upregulation of defense-related genes and activation of key signaling pathways. • Melatonin potentiates SA signaling pathway, upregulates antioxidant enzyme genes, and activates the MAPK cascade, and WRKY transcription factors, thereby reducing fungal colonization. • TaRAR1 is strongly upregulated during early stages of infection in incompatible interactions and is required for Lr10 -mediated resistance. • TaRAR1 silencing compromised TcLr10 resistance, resulting in reduced endogenous SA and melatonin levels, downregulated defense-related genes and reduced hydrogen peroxide accumulation. • Furthermore, silencing of TaRAR1 significantly downregulated TaSGT1 and TaHSP90 expression, indicating its key function as a cochaperone in stabilizing R -gene mediated defense signaling. Wheat leaf rust, caused by the biotrophic fungal pathogen Puccinia triticina ( Pt ), continuously threatens global wheat production, causing considerable yield losses necessitating the implementation of effective management approaches. While conventional breeding and chemical control strategies have been used, priming agents and genetic regulators offer sustainable strategies for wheat leaf rust management. Melatonin (N-acetyl-5-methoxytryptamine), a pleiotropic signaling molecule, induces plant innate immunity against abiotic and biotic stresses. This study demonstrates that exogenous melatonin (100 µM) enhances Lr1...