At a global scale, only 12 grape varieties (representing only 1% of the cultivated varieties available) make up nearly 80% of the vineyards of certain countries.
Earlier harvest dates, droughts affecting grape vines, or wines with higher alcohol content, less acidity and new aromatic profiles all show that the winemaking industry is already affected by climate change, and scientists are studying different adaptation strategies for these challenges.
Researchers from the French Institute of Agronomic Research (INRA) and Harvard University suggest that an important tool in adapting the wine industry to climate change is to take advantage of the diversity of other grape varieties that are less frequently used by winemakers to help the industry adapt to new climates in winemaking regions, by planting less known varieties and by encouraging new practices among producers and consumers. Their study was published in Nature Climate Change on Jan. 2, 2018.
To do this, the researchers first used knowledge of the genetic diversity of vines taken from scientific literature. In particular, the analyzed date from the INRA center of biological resources of vines in Vassal-Montpellier, which constitutes a collection that is unique in the world. This conservatory of reference at the international level is composed of vines coming from 54 winemaking countries (2,700 grape varieties, 350 wild vine species, 1,100 hybrid species, 400 rootstocks and 60 vine species).
They complemented this knowledge with a database published by Australian researchers which describes the global distribution of grape varieties planted in all vineyards. An overall analysis of this data allowed for the observation that winegrowers only use a very small proportion of the genetic diversity available at a global level. Indeed, only 1% of varieties occupy about 45% of the space in vineyards around the world. And in certain countries, up to 75% of surfaces are devoted to a single grape variety, Cabernet-Sauvignon.
However, among the thousands of different types of grapes, certain are better adapted to hotter climates and have better results in drought than the 12 well-known grapes that are the most frequently used in the world. It is thus important to better understand and to experiment with the grapes coming from other places in the different production zones in order to evaluate their potential in the face of future climate changes.
This study suggests the need to better involve winemakers in the testing and evaluation of new grape varietals. It would also be beneficial to encourage winemakers to share their data with scientists, through perhaps experiments of participative science in order to together construct strategies for adapting to the climate of tomorrow and to avoid suffering from the negative effects of climate on their production.