The adaptation and resilience of scions and rootstocks to water constraint

Smoke impacts on wines are becoming a worldwide problem; the size and severity of wildfires increasing due to influences from changing climates.¹ For over a century, wines have been known to have a unique issue of absorbing chemical compounds derived from wildfire smoke wherein the flavor of the subsequent wine becomes ashy, rubbery, campfire-like, and smoky.² The economic impacts of a smoke-impacted wine can last for years depending on the grape varietal, costing Oregon and Washington states in the United States over a billion dollars from the 2020 wildfires, as an example.³ While years of research have indicated elevated concentrations of smoke-related compounds, such as guaiacol and syringol, in wines after smoke events, unfortunately, replicating the sensory experience using smoke-associated phenols has not had much success.⁴

En France, la notion de Terroir a largement contribué à la réputation de nombreux vignobles. Elle a permis aussi d’accentuer la sensibilité des consommateurs, à la notion d’origine d’un produit. L’avenir de nombreux vignobles français semble lié à la capacité à innover en produisant des vins de qualité possédant en plus une typicité, aspect sensoriel susceptible de s’affirmer comme un facteur de vente auprès des futurs clients éduqués sur le plan du goût.

Wines exhibit profound chemical complexity which arise from a diverse array of compounds that contribute to its sensory profile.

Vine water status is a crucial determinant of vine growth, productivity, fruit composition and terroir or wine style; therefore, regulating water stress is of great importance. Since vine water status depends on both soil moisture and aerial environment and is very temporally dynamic, direct measurement of vine water potential is highly preferable. Current methods only provide limited data. To regulate vine water status it is critical to monitor vine water status to be able to: (1) measure vine water status to predict the effect of water stress on the overall vineyard performance and fruit quality and optimize harvest management and wine-making (2) properly regulate the water status to impose for a desired fruit quality or style (3) determine if water management has reached the desired stress level.

Since the emergence of phylloxera, grafting has been the most used propagation method in viticulture. Despite all the improvement measures implemented in the nurseries, it is frequent that graft success rates vary depending on the nursery process and scion/rootstock combinations. The reasons behind this unsatisfactory behaviour are still unknown and can be diverse, although carbohydrate reserves might be hypothesised to be crucial, since callus, root, and new tissue formation will be built based on them. In order to identify the effect of carbohydrates on grafting success, nine combinations were established based on the starch content in grapevine scionwoods (cv. Tempranillo clone VN69) and rootstocks cuttings (110 Richter clone 237) used for grafting: Low (L), Medium (M), High (H).