Rootstock-scion contributions to seasonal water and light use diversity under field conditions

Grape quality potential for wine production is strongly influenced by environmental parameters and agronomic factors. Several studies underline the rootstock effect on scions vegetative growth and berry composition [1] with an impact on wine quality. Rootstocks are promising agronomic tools for climate change adaptation and in most grape-growing regions the potential diversity of rootstocks is not fully used and only a few genotypes are planted. Moreover, little is known about the effect of rootstock genetic variability on the aromatic composition in wines.

Just over 150 years ago, phylloxera, daktulosphaera vitifoliae, was introduced to europe, and particularly france, from north america via imports of american vitis plants. This aphid, with its complex biology and life cycle, has spread rapidly to most vineyards, causing rapid and lethal decline of v. Vinifera vines due to the primary and secondary damage it causes to the roots. In response to this pest, and given the economic importance of the french wine sector, professional representatives organised into ‘agricultural societies’, scientists and public authorities rallied together to identify the exact causes, seek solutions and try to stem the serious socio-economic crisis that ensued.

In winemaking grapes, it is known that most aroma compounds are present as non-volatile precursors, such as glycosidic precursors. In fact, there is strong evidence supporting the connection between the content of aroma precursors and the aromatic quality of wine [1]. Acid hydrolysis is preferred to reveal the aroma potential of winemaking grapes, as it predicts more accurately the chemical rearrangements occurring during fermentation in acidic environments [2]. In this study, a method involving a fast fermentation followed by acid hydrolysis at 75ºC was used to evaluate the accumulation of aroma compounds over time in fractions obtained from six different varieties of winemaking grapes.

Global changes and sustainability challenge researchers in saving water and nutrients. The response of woody crops, which can be forced at facing more drought events during their life, is particularly important. Vitis vinifera can be an important model for its relevance in countries subjected to climate changes and its breeding, requiring cuttings plantation and strong pruning.

The National Plant Germplasm System (NPGS) in the United States Department of Agriculture safeguards numerous species. Grapevines are split in two locations: Davis, CA and Geneva, NY. The two germplasms maintain 43 Vitis species with over 4500 genetically unique accessions.