Faced with global warming, which promises New Aquitaine to experience in a few years the climate of Seville, the vine is particularly exposed. Changes have already been observed, such as an earlier flowering and harvesting period, an increase in alcohol content… Research programs and experiments are multiplying in an attempt to find an appropriate response.
The prize for the most innovative program, and perhaps the most expensive, goes unquestionably to the start-up Space Cargo Unlimited, which tries neither more nor less to find the solution… in space. With its Wise mission, the Bordeaux start-up has indeed sent vine plants to the international space station, in an attempt to create a new variety that would be more resistant to the phenomenon of global warming, or to diseases.
Plants that grow faster
And the first results of this experiment are “exciting” confides Nicolas Gaume, boss of Space Cargo Unlimited. The Wise mission had sent, in November 2019 then in March 2020, 12 bottles of Petrus vintage 2000, then 320 vine plants – 50% merlot and 50% cabernet sauvignon – on the ISS. The shipments had been recovered in January 2021, then the 320 vine plants had been replanted in the greenhouse, in order to compare their growth with 320 other vine plants remaining on Earth.
A year and a half later, the 320 plants have grown, allowing a new planting campaign at the start of 2022 which has given birth to “thousands of plants”. Concretely, “we have been able to observe that our space plants develop much more quickly than those remaining on earth, and that they put in place appropriate responses to external aggressions. »
Lack of gravity creates considerable stress on plants
Example with the mildew, “disease that we do not know how to treat, except with Bordeaux mixture which is not ideal”, recalls Nicolas Gaume. “We exposed the leaves of our plants to this disease, with the result: 100% of terrestrial vine plants died, while the vast majority of space plants survived. We then selected the plants that survived, which we replanted to see how they will evolve. Important detail: “The characteristics acquired by plants in space are permanent: it’s like when you create a new variety of rose by cutting several roses. »
How to explain this difference? By gravity, or rather the absence of gravity. The idea of the Wise mission was effectively to expose the vine plants at a precise moment in their development, that is to say when young, to this very particular spatial environment, since it is deprived of gravity.
“When you remove an element as essential to life as gravity, it creates considerable stress on living organisms, which leads nature to find adjustment strategies,” explains Nicolas Gaume. The plant finds natural response mechanisms to survive, and gains in adaptability in the face of lesser but nonetheless calamitous stresses, such as water or temperature stress, or in the face of pathogens such as mildew. »
Create vines “more resistant to disease and climate change”
The start-up Space Cargo Unlimited also indicates that, “compared to control plants remaining on Earth, more advanced genetic analyzes on space vine shoots show changes in more than 90 genes linked to basic metabolism, and to the responses of defense of space vine shoots on the leaves of Merlot. Space Cargo Unlimited is now awaiting confirmation of these findings during outdoor replanting.
These initial results therefore confirm the objective of the Wise mission, which is to create vines that are “more resistant to disease and climate change” with, in particular, plants that consume less water. “However, we remain cautious, we are only halfway through our experimentation and we will have to wait to go to the end of the cycle” warns Nicolas Gaume.
A new planting cycle will indeed be necessary to reach definitive conclusions. “For example, we tested mildew on the leaves of the plants but not on the roots, which we are going to do this summer, to go further in the experiment. »
We must now “ensure the taste qualities of the grapes”
It will also be necessary to ensure the taste qualities of the grapes given by these Merlot and Cabernet Sauvignon grape varieties, the most used in Bordeaux, when the warming poses the threat of having to use other grape varieties. “We are waiting for a sufficient quantity of grapes, continues Nicolas Gaume, and we think that this will not be the case this year to carry out vinification, that is why we will replant next year to ensure ensure that it is suitable for wine production with all the health guarantees, which are our obsession. »
All these experiments “are very supervised, in certified laboratories and controlled greenhouses”, insists the boss of Space Cargo Unlimited. The start-up has a partnership with the ISVV, the Institute of Vine and Wine Sciences based in Villenave-d’Ornon in the suburbs of Bordeaux, “one of the largest vine and wine research laboratories in the world. »
Another partnership, which will be decisive for the continuation of the project, is that signed with the Mercier group, “the largest wine nurseryman who supplies most of the great castles” underlines Nicolas Gaume. Because it is thanks to him that “we hope to offer our more resistant vine plants to winegrowers. »