Probabilistic modeling of the quality of a vineyard and deterministic modeling of the quality of a wine: first approaches

The French official catalog now includes more than 350 varieties. Each year, new varieties join the list. With, anytime, the ambition to give opportunities to meet the challenges that wine industry is facing. High hopes and expectations are based on the vine material in order to face climate change, reduction of chemicals or the ability to maintain the competitiveness.

It is 40 years since I made my first harvest of Syrah vines in the hot climate of Griffith, NSW, Australia. The commercial vineyards of the region were healthy and vigorous, extensively cultivated with heavy and wide tractors, own-rooted, flood irrigated, relatively high yielding (to 30 t/ha), hand pruned and harvested, and with non-positioned, highly-shaded canopies producing bulk wine in general.

Grapevines are cultivated on 6 out of 7 continents, between latitudes 4° and 51° in the Northern Hemisphere and between 6° and 45° in the Southern Hemisphere across a large diversity of climates (oceanic, warm oceanic, transition temperate, continental, cold continental, Mediterranean, subtropical, attenuated tropical, and arid climates).

A production system is sustainable if it meets four conditions: it is profitable, accounts for environmental and social expectations and ensures product safety. The challenges for sustainability in the vineyard and winery overlap partially. The latest Australian Wine Industry Environment Conference highlighted four aspects relevant to sustainability: profitability, water, energy and warming climate.

For the last forty years, Swiss research in Viticulture was focused on a model of sustainable production. One of its central objectives is the selection of grapevines adapted to the Swiss pedoclimatic context and highly resistant to the main cryptogamic diseases.