Glycerol-Induced Powdery Mildew Resistance in Wheat by Regulating Plant Fatty Acid Metabolism, Plant Hormones Cross-Talk, and Pathogenesis-Related Genes.

Yinghui Li,Tamar Krugman,Qixin Sun,Chaojie Xie,Tzion Fahima,Qiang Zhang,Xiangxi Zhuansun,Xinye Liu,Lina Qiu

doi:10.3390/ijms21020673

Abstract

Our previous study indicated that glycerol application induced resistance to powdery mildew (Bgt) in wheat by regulating two important signal molecules, glycerol-3-phosphate (G3P) and oleic acid (OA18:1). Transcriptome analysis of wheat leaves treated by glycerol and inoculated with Bgt was performed to identify the activated immune response pathways. We identified a set of differentially expressed transcripts (e.g., TaGLI1, TaACT1, and TaSSI2) involved in glycerol and fatty acid metabolism that were upregulated in response to Bgt infection and might contribute to G3P and OA18:1 accumulation. Gene Ontology (GO) enrichment analysis revealed GO terms induced by glycerol, such as response to jasmonic acid (JA), defense response to bacterium, lipid oxidation, and growth. In addition, glycerol application induced genes (e.g., LOX, AOS, and OPRs) involved in the metabolism pathway of linolenic and alpha-linolenic acid, which are precursor molecules of JA biosynthesis. Glycerol induced JA and salicylic acid (SA) levels, while glycerol reduced the auxin (IAA) level in wheat. Glycerol treatment also induced pathogenesis related (PR) genes, including PR-1, PR-3, PR-10, callose synthase, PRMS, RPM1, peroxidase, HSP70, HSP90, etc. These results indicate that glycerol treatment regulates fatty acid metabolism and hormones cross-talk and induces the expression of PR genes that together contribute to Bgt resistance in wheat.

Highlights

Bread wheat (Triticum aestivum L.) is one of the most important food crops worldwide
We found that glycerolipid metabolism and fatty acid biosynthesis pathways were in response to Blumeria graminis f.sp. tritici (Bgt) infection, which might contribute to G3P and OA18:1 accumulation
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Summary

Introduction

Bread wheat (Triticum aestivum L.) is one of the most important food crops worldwide. Tritici (Bgt), is an obligate biotrophic ascomycete fungus that invades the aerial parts of wheat, causing powdery mildew disease. The damage caused by Bgt can result in yield losses from 30% to 40% in years with severe epidemics [1,2]. Deployment of resistance (R) genes and spraying with foliar fungicides are the common methods for diseases control in wheat. Many R genes lost their effectiveness due to the appearance of new pathogen races, and fungicides are not always economically feasible and environmentally friendly. New sustainable effective ways for disease control in wheat are needed

Methods

Results

Conclusion