Using δ13C and hydroscapes as a tool for discriminating cultivar specific drought response

In this video recording of the IVES science meeting 2021, Sophie Tempère (Institut des Sciences de la Vigne et du Vin – ISVV, Université de Bordeaux) speaks about the recovery of olfactory capacity following a COVID-19 infection. This presentation is based on an original article accessible for free on IVES Technical Reviews.

As an essential element for grapevine development and yield, nitrogen is also involved in the winemaking process and largely affects wine composition. Grape must amino nitrogen deficiency affects the alcoholic fermentation kinetics and alters the development of wine aroma precursors. It is therefore essential to control and optimize nitrogen use efficiency by the plant to guarantee suitable grape nitrogen composition at harvest. Understanding the impact of environmental conditions and cultural practices on the plant nitrogen metabolism would allow us to better orientate our technical choices with the objective of quality and sustainability (less inputs, higher efficiency). This trial focuses on the impact of crop limitation – that is a common practice in European viticulture – on nitrogen distribution in the plant and particularly on grape nitrogen composition. A wide gradient of crop load was set up in a homogeneous plot of Chasselas (Vitis vinifera) in the experimental vineyard of Agroscope, Switzerland. Dry weight and nitrogen dynamics were monitored in the roots, trunk, canopy and grapes, during two consecutive years, using a 15N-labeling method. Grape amino nitrogen content was assessed in both years, at veraison and at harvest. The close relationship between fruits and roots in the maintenance of plant nitrogen balance was highlighted. Interestingly, grape nitrogen concentration remained unchanged regardless of crop load to the detriment of the growth and nitrogen content of the roots. Meanwhile, the size and the nitrogen concentration of the canopy were not affected. Leaf gas exchange rates were reduced in response to lower yield conditions, reducing carbon and nitrogen assimilation and increasing intrinsic water use efficiency. The must amino nitrogen profiles could be discriminated as a function of crop load. These findings demonstrate the impact of plant balance on grape nitrogen composition and contribute to the improvement of predictive models and sustainable cultural practices in perennial crops.

The wine region of “Vinhos da Campanha” is located in southern Brazil, on the Uruguay borderline. The colonization’s process in the region was characterized by territorial disputes between Portuguese

The use of cover crops (CCs) is widely proposed as an alternative to traditional soil management in vineyards to exploit a wide range of ecosystem services. The presence of a CC in the inter-row space is known to control spontaneous vegetation in vineyards, primarily through the biomass of the sown crop, which competes with other spontaneous species for soil resources.

In this work we present a joint model of calculation the budbreak and full bloom starting dates which considers the heat sums and allows reliable estimations for five white wine grape varieties