Vine decline mechanisms, from physiology to pathology

^{Keywords : carbon depletion, hydraulic dysfunction, wood diseases, foliar diseases, water stress}

The aim of the Physiopath project is to identify the mechanisms behind vine dieback through an integrated approach, combining biotic interactions and the physiology of the host plant. The hydraulic properties of the vascular system (conductive tissue for xylem sap, and dispersion site for vascular pathogenic agents) will be studied, as well as their roles in the vine’s vulnerability to vascular diseases and to drought. The vine’s physiological response (hydraulic and carbon dysfunction) to biotic constraints (vascular and foliar diseases) and abiotic constraints (drought) will be studied. This project will ultimately lead to the identification of thresholds for these constraints, beyond which dieback will occur in the vineyard. This project will help to remove some of the unknowns concerning pathology and ecophysiology, in order to identify tools for diagnosing vine dieback which can be used by the wine growing profession.

Partners

Led by Chloé Delmas at the UMR Vineyard Health and Agroecology (SAVE) in Bordeaux, the project calls upon the expertise of four other INRA research units: the UMR Vine Ecophysiology and Functional Genomics (EGVF), the UMR Genes and Communities Biodiversity (BIOGECO), both in Bordeaux; the Laboratory of Plant Ecophysiological Responses to Environmental Stresses (LEPSE) in Montpellier, and the Pech Rouge Experimental Unit, near Narbonne.

Actions

• Action 1 : Interaction between the properties of the vessels, the hydraulic functioning, and the vine’s susceptibility to pathogenic agents.
• Action 2 : Impact of the biotic and abiotic factors on vine physiology.
• Action 3 : Indicators of biotic and abiotic factors: identification of thresholds beyond which vine dieback occurs.

Programme

The Physiopath project started in Autumn 2017 and the various studies will continue until March 2021.

Photo : Inra A.Girard