Exploring grapevine water relations in the context of fruit growth at pre- and post-veraison

The Languedoc-Roussillon wineries are facing a decline in wine yields particularly PGI yields due to many factors. Climate change is just ones, but is expected to increase in the future. There is also structurally a large heterogeneity of yield profiles among terroirs, varieties and strategies. This work investigates the link between yield, competitiveness and resilience to explore how resilient winegrowers have been in the recent past. To this end two approaches have been combined; (i) an accountancy database analysis at estate scale and (ii) municipality level competitiveness analysis. A new resilience indicator that characterizes the capacity of an estate to absorb yield variation is also defined. The FADN database between 2000 and 2018 of ex-Languedoc-Roussillon (France) and other data are used to analyse the current situation and the past evolution of competitiveness and resilience by type of estate (type of farm: PGI and/or PDO & type of commercialization: bulk and/or bottles). The net margin, which defines competitiveness, is not correlated to yield for all types but depends on the type of commercialization and the level of specialisation. The resilience indicator shows that the net margin of estates specialized in PGI is particularly sensitive to yield declines. We also show that price evolutions seem to compensate the effect of yield losses for the majority of types. Municipality scale analysis shows the links between local pedoclimate, yield, commercialization strategies and price. Overlapping a PDO with a PGI does not always increase a municipality’s PGI competitiveness. It is difficult to make links between causes and effects due to the complexity of the wine production system. Production diversification may be a solution. Resorting to the two level of analysis helps resolving the data gap that is necessary to explore the links between yield and economic performance of the wine estates in the long term.

A critical aspect of wine quality is the overall expression of wine flavour, which is formed by the interplay of volatile aroma compounds, their precursors, and taste and matrix components.
Grapes directly contribute to wine only a small number of potent aroma compounds, and the unique
sensory attributes and perceived quality of a wine result from combining 100s of metabolites of grapes, yeast and bacteria, and oak wood.

The USDAAgricultural Research Service maintains Vitis germplasm repositories in Geneva, NY and Davis, CAcollectively preserving approximately 5,000 unique accessions representing 30 Vitis species.

To understand how phenolic composition and structural modifications impact astringency, research scale (120L) Petite Verdot wines were made to allow for a full-factorial design altering pH (3.25, 3.5, 3.75, 4.0) and oxidative and reductive adjuvants (glutathione, GSH, sulfur dioxide, SO2, and acetaldehyde) in triplicate.

In the Table Grape Breeding Program developed at the Junín, Mendoza, Rama Caída and San Juan Agricultural Experimental Stations of the National Institute of Agricultural Technology (INTA), the cultivars Delicia INTA, Fernandina INTA, Serena INTA and Sorpresa INTA were obtained.