Extension to the Saumurois-Touraine area of an Anjou-originated method for the characterisation of the viticultural terroirs. (Loire Valley, France)

Les indices bioclimatiques constituent un bon outil pour piloter le développement vitivinicole dans une région précise

Drought caused by climate change has a dramatic incidence on the vineyard. Despite employing specific rootstocks tolerant to drought like 110 Richter, the vineyard continues to experience various losses, revealing the importance of the scion cultivar in the adaptation to drought stress. In this regard, Merlot, a widely cultivated grapevine, exhibited reduced drought tolerance compared to less cultivated varieties like Callet, a local cultivar originating from the Balearic Islands that demonstrated greater resilience to drought. Therefore, understanding the drought stress response in both cultivars and the cross-talk between scion and rootstock is key to unveiling possible differences that could affect to the adaptation to drought in vineyard.

Agriculture, natural resource management and the production and sale of products such as wine are increasingly data-driven activities. Thus, the use of remote and proximal crop and soil sensors to aid management decisions is becoming commonplace and ‘Agtech’ is proliferating commercially; mapping, underpinned by geographical information systems and complex methods of spatial analysis, is widely used. Likewise, the chemical and sensory analysis of wines draws on multivariate statistics; the efficient winery intake of grapes, subsequent production of wines and their delivery to markets relies on logistics; whilst the sales and marketing of wines is increasingly driven by artificial intelligence linked to the recorded purchasing behaviour of consumers. In brief, there is data everywhere!

Opinions will vary on whether these developments are a good thing. Those concerned with the ‘mystique’ of wine, or the historical aspects of terroir and its preservation, may find them confronting. In contrast, they offer an opportunity to those interested in the biophysical elements of terroir, and efforts aimed at better understanding how these impact on vineyard performance and the sensory attributes of resultant wines. At the previous Terroir Congress, we demonstrated the potential of analytical methods used at the within-vineyard scale in the development of Precision Viticulture, in contributing to a quantitative understanding of regional terroir. For this conference, we take this approach forward with examples from contrasting locations in both the northern and southern hemispheres. We show how, by focussing on the vineyards within winegrowing regions, as opposed to all of the land within those regions, we might move towards a more robust terroir zoning than one derived from a mixture of history, thematic mapping, heuristics and the whims of marketers. Aside from providing improved understanding by underpinning terroir with data, such methods should also promote improved management of the entire wine value chain.

Aim: Several plant-based indicators of vine N status are reported in the literature. Among these, yeast assimilable nitrogen in grape must (YAN) and total N concentration of petiole and leaf blades are considered to be reliable indicators and so is the chlorophyll index, measured with a device called N-tester. The N-tester index is used to measure the intensity of the green colour of the leaf blade, and therefore to estimate its chlorophyll content.

Un paysage viticole est une relation entre des formes, dimension objective, et la perception que nous en avons, dimension subjective, émotionnelle. La viticulture n’est pas seulement productrice d’un vin, elle contribue également à façonner le paysage. Pourtant, jusqu’à présent, la connaissance des terroirs était principalement basée sur la caractérisation de leur aptitude à produire des vins de qualité.