title: NMR metabolomics of esca disease-affected Vitis vinifera cv. Alvarinho leaves.
abstract: Esca is a destructive disease that affects vineyards leading to important losses in wine production. Information about the response of Vitis vinifera plants to this disease is scarce, particularly concerning changes in plant metabolism. In order to study the metabolic changes in Vitis plants affected by esca, leaves from both infected and non-affected cordons of V. vinifera cv. Alvarinho (collected in the Vinho Verde region, Portugal) were analysed. The metabolite composition of leaves from infected cordons with visible symptoms [diseased leaves (dl)] and from asymptomatic cordons [healthy leaves (hl)] was evaluated by 1D and 2D (1)H-nuclear magnetic resonance (NMR) spectroscopy. Principal component analysis (PCA) of the NMR spectra showed a clear separation between dl and hl leaves, indicating differential compound production due to the esca disease. NMR/PCA analysis allowed the identification of specific compounds characterizing each group, and the corresponding metabolic pathways are discussed. Altogether, the study revealed a significant increase of phenolic compounds in dl, compared with hl, accompanied by a decrease in carbohydrates, suggesting that dl are rerouting carbon and energy from primary to secondary metabolism. Other metabolic alterations detected comprised increased levels of methanol, alanine, and gamma-aminobutyric acid in dl, which might be the result of the activation of other defence mechanisms.
authors: University of Minho, Department of Biology, CITAB-Centro de Investigação e de Tecnologias Agro-Ambientais e Biológicas, Campus de Gualtar, 4710-057 Braga, Portugal.
authors: Marta R M
authors: MR
authors: Lima
authors: Mafalda L
authors: ML
authors: Felgueiras
authors: Gonçalo
authors: G
authors: Graça
authors: João E A
authors: JE
authors: Rodrigues
authors: António
authors: A
authors: Barros
authors: Ana M
authors: AM
authors: Gil
authors: Alberto C P
authors: AC
authors: Dias
mesh_terms: D009682:Magnetic Resonance Spectroscopy; D055432:Metabolomics; D010935:Plant Diseases; D018515:Plant Leaves / Q000378:metabolism; D025341:Principal Component Analysis; D027843:Vitis / Q000737:chemistry / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D005680:gamma-Aminobutyric Acid