Integrated transcriptomic and metabolomic analysis revealed the potential role of hesperetin in wheat resistance to leaf rust.
TL;DR
Findings indicated that hesperetin may serve as a potential defense compound in wheat during the early stages of leaf rust infection, providing crucial insights for developing novel natural products and a theoretical foundation for genetic improvement in disease-resistant wheat breeding.
Abstract
Background
Natural plant metabolites, such as flavonoids and lignin, exhibited safe and environmentally friendly roles in defending against pathogen attack. However, their functional roles in the interaction between wheat and Puccinia triticina (Pt) remained poorly characterized.
Results
In this study, we integrated transcriptomic and quasi-targeted metabolomic analyses to systematically characterize differentially expressed genes (DEGs) and metabolites associated with the compatible and incompatible interactions between wheat and Pt. In the wheat-Pt interaction system, a total of 1,242 metabolites were identified, predominantly classified into amino acids and derivatives, flavonoids, and related compound classes. In the flavonoid and lignin biosynthesis-related pathways-namely, Flavonoid biosynthesis and Phenylpropanoid biosynthesis-significant differences were observed in both the accumulation levels of key metabolites and the expression of genes associated with their biosynthetic pathways. Notably, in the incompatible interaction, the expression of TaCAD, a gene implicated in syringyl lignin (S-lignin) biosynthesis, was significantly up-regulated. Gene regulatory network (GRN) analysis further suggested that transcription factors (TFs) including ERF, LBD, BBR-BPC, and C2H2 may play critical regulatory roles in mediating wheat resistance to leaf rust. Moreover, the key flavonoid hesperetin was markedly enriched in the incompatible combination (TcLr24_120 h vs. TcLr24_0 h). Exogenous application of hesperetin significantly inhibited urediniospores germination in vitro. More importantly, it significantly reduced disease severity of wheat leaf rust in vivo.
Conclusions
These findings indicated that hesperetin may serve as a potential defense compound in wheat during the early stages of leaf rust infection, providing crucial insights for developing novel natural products and a theoretical foundation for genetic improvement in disease-resistant wheat breeding.