UPLC-QTOF-MS metabolomics analysis revealed the contributions of metabolites to the pathogenesis of Rhizoctonia solani strain AG-1-IA

• Published in: PloS one 2018-02, Vol.13 (2), p.e0192486-e0192486
• Main Authors: Hu, Wenjin, Pan, Xinli, Li, Fengfeng, Dong, Wubei
• Format: Article
• Language: English
• Subjects: Acids; Analysis; Arabidopsis thaliana; Biology and Life Sciences; Cell cycle; Chemical synthesis; Chemometrics; Chromatography; Corn; Crop diseases; Discriminant analysis; Diseases and pests; Gene expression; Genetic aspects; Glutamic acid; Growth; Infections; Jasmonic acid; Leaves; Liquid chromatography; Mass spectrometry; Mass spectroscopy; Medicine and Health Sciences; Metabolism; Metabolites; Metabolomics; Pathogenesis; Phenylacetic acid; Physical Sciences; Phytotoxins; Plant diseases; Plant growth; Plant pathology; Plant resistance; Plant sciences; Plant tissues; Plant-pathogen relationships; Principal components analysis; Quercetin; Research and Analysis Methods; Rhizoctonia solani; Rhopalosiphum maidis; Rutin; Sheaths; Signal transduction; Signaling; Zeaxanthin
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0192486

To explore the pathogenesis of Rhizoctonia solani and its phytotoxin phenylacetic acid (PAA) on maize leaves and sheaths, treated leaf and sheath tissues were analyzed and interpreted by ultra-performance liquid chromatography-mass spectrometry combined with chemometrics. The PAA treatment had similar effects to those of R. solani on maize leaves regarding the metabolism of traumatin, phytosphingosine, vitexin 2'' O-beta-D-glucoside, rutin and DIBOA-glucoside, which were up-regulated, while the synthesis of OPC-8:0 and 12-OPDA, precursors for the synthesis of jasmonic acid, a plant defense signaling molecule, was down-regulated under both treatments. However, there were also discrepancies in the influences exhibited by R. solani and PAA as the metabolic concentration of zeaxanthin diglucoside in the R. solani infected leaf group decreased. Conversely, in the PAA-treated leaf group, the synthesis of zeaxanthin diglucoside was enhanced. Moreover, although the synthesis of 12 metabolites were suppressed in both the R. solani- and PAA-treated leaf tissues, the inhibitory effect of R. solani was stronger than that of PAA. An increased expression of quercitrin and quercetin 3-O-glucoside was observed in maize sheaths treated by R. solani, while their concentrations were not changed significantly in the PAA-treated sheaths. Furthermore, a significant decrease in the concentration of L-Glutamate, which plays important roles in plant resistance to necrotrophic pathogens, only occurred in the R. solani-treated sheath tissues. The differentiated metabolite levels may be the partial reason of why maize sheaths were more susceptible to R. solani than leaves and may explain the underlying mechanisms of R. solani pathogenesis.