Freeze-thaw temperature oscillations promote increased differential gene expression during grapevine bud dormancy

Knowledge of the nitrogen nutrition status of grapevines is essential for the sustainable management of their nutrition for the production of quality grapes. The measurement of the chlorophyll index is a rapid, non-destructive and relatively inexpensive method that provides a good approximation of the nitrogen nutrition status of the vine during the season. Interpretation thresholds are currently insufficient or non-existent for some chlorophyll meters. Ideally, they should be available for each variety and each phenological stage. In order to popularize the use of chlorophyll-meters, measurements were carried out at Agroscope in Switzerland to establish the correlation between the indices obtained by the devices N-tester and SPAD 502.

In the context of global change, the environmental conditions are expected to be more stressful for viticulture. The choice of the rootstock may play a crucial role to improve the adaptation of viticulture to new biotic and abiotic threats (Ollat et al., 2016). However, the selection of interesting traits in rootstock breeding programs is complex because of the combination of multiple targets in a same ideotype. In this sense, the integration of studies about the genetic architecture for desired biotic and abiotic response traits allow us to identify genomic regions to combine and those with interesting pleiotropic effects.

Vineyards are home to a myriad of microorganisms that interact with each other and with the vines. Some microorganisms are plant pathogens, such as the oomycete Plasmopara viticola, causing grapevine downy mildew. Others have a positive effect on vine health, such as disease biocontrol agents. These beneficial plant-microbe and microbe-microbe interactions have gained more attention in recent years because they could represent an alternative to the use of fungicides in viticulture.

The Douro demarcated region constitutes just over 50% of the area of mountain vineyard in the world, i.e., vineyards with slope gradients of 30% or above. Among the different (terraced) vineyard layouts, the formerly preferred wider terraces supporting two rows of vines and the currently advocated narrower single vine row, dominate the vineyards’ planting layout. The slope of these terraces, in other words, the supporting earth ramp, is a key element in these vineyards’ construction.

High quality wines start in the vineyard however little is known about the role vineyard management practices play in this quality outcome. Gold medals and well-known regionality increase consumer preference for purchasing a wine. An increase in the former will certainly also drive an increase in the latter and therefore practices in production that consistently lead to gold medal winning wines will improve both the marketability of the region and its products. It is argued that vinification is the main driver of wine quality and in fact, the presence of some oak compounds is a well-known consumer and expert mark of quality. However, only select wines are vinified in oak and therefore the original grape quality at the winery door must in fact drive all further downstream vinification decisions.