Grape seeds, used to make wine and found at archaeological sites across Europe, have been genetically tested and tell a story of continuity from ancient Rome to the present day. It seems that some of the wines drunk by the Romans, which were drunk in the Middle Ages and modern times, were produced with very similar grape varieties as are used today. This was the continuity of the use of grapevines over the centuries.
The aim of the research was to understand the origin of winemaking in France, which has confused people for many years. It not only reveals the history of grape varieties, but also provides data showing that the wine industry may be vulnerable to climate change.
The study involved a large multidisciplinary team of researchers from several European countries, including the UK, Denmark, France and Germany. It was funded by a Danish and a French research agency. The researchers tried to understand the genomes of the old grapes. Their results were published in the journal Nature Plants.
Comparison of the old and the new grape DNA
The researchers used a large database containing information about the genome of many modern grapes used for winemaking. These were compared to the genetics of grape seeds found in a number of archaeological sites. Technology News reports that "researchers were able to test and compare 28 archaeological seeds from French Iron Age, Roman, and Middle Ages sites." In the recent past, DNA tests were used to study the origin of grapes grown in modern vineyards. According to Decanter.com "there are still some gaps in the family jigsaw of modern varieties".
Waterborne Roman grape seeds like these have been genetically tested in the past to study grape varieties. Credit: L. Bouby, CNRS / ISEM
The European researchers, who worked separately but worked closely together, used the same DNA techniques that identified the ancestors of modern man. Phys.org reports that the experts were able to "establish genetic links between seeds from various archaeological sites".
Then, by comparing genomes, they were able to establish the relationship between ancient seeds and modern grape varieties.
The Roman Connection
The researchers found that the archaeological samples were closely related to Western European varieties that are used today for vinification, according to Nature Plants. The multidisciplinary team was able to find genetic traces indicating that Roman and later grapes were related. According to Phys.org, some of the seeds were identified as having "18 different genetic signatures, including one set of genetically identical seeds from two Roman sites."
These two Roman sites were 600 km apart and date back two millennia. Interestingly, they also have something to do with many grapes that are still grown in French alpine vineyards. This indicates a great continuity in the proliferation of grapes in Western Europe since Roman times. This was mainly due to the abilities of the winegrowers with asexual reproduction and the use of Weinstecklingen that preserved the genetic signatures of the grapes.
Bacchus, Roman god of agriculture, wine and fertility by Peter Paul Rubens. ( Public Domain )
Recent research has shown that it is possible to identify the relationships between Roman and modern wine. Due to the writings of classics like Pliny the Elder, we know the name of many Roman wines. Dr. Jazmín Ramos-Madrigal, one of the co-authors of the study, said: "Now we have the opportunity to know exactly what the Romans are doing in their vineyards using genetics," reports Technology News.
Dr. Nathan Wales of the University of York, a member of the research team, said that "the Syrah-Mondeuse Blanche family and the Pinot-Savagnin family" attribute their ancestors to Roman vineyards, according to Phys.org. This means that the people who lived in the Roman Empire made wine that was similar to ours and tasted very similar. However, it seems that the taste has changed and some popular grapes in the past are not so popular today.
While the study found a relationship between Roman seeds and modern grapes, they were not directly related. However, researchers found a close genetic match between a medieval seed from a vineyard in Orleans, France, and the grape used to make Savagnin Blanc. This is a wine that is not very popular but is still produced and is often known as Traminer Weiss.
It has been found that an ancient Savagnin Blanc grape seed is directly related to the modern variety. CC BY-SA 4.0 )
The danger of global warming
The genetic heritage of many modern grapes has a great continuity with the past. This means that there is a lack of genetic diversity. This could be problematic and even pose an existential risk to future winemaking, especially as our climate warms. Global warming and more extreme weather events could pose a real threat to winemaking in the future, as they could destroy whole crops and make grape varieties disappear.
These and other studies show that it is necessary to develop new grape varieties that are more resistant. National Public Radio quotes Zoë Migicovsky, a Canadian postdoctoral researcher who is investigating the resilience of the wine, saying we need to adjust to "harder grapes". This is the only way to survive winemaking, but it can be expensive to lose loved drops like Merlot and Pinot-Grigio.
The study is important because it allows us to better understand the evolution of winemaking. It also shows how much wine lovers owe the Romans for their favorite drinks. Research also shows that grapes have a dangerous lack of genetic diversity that could make them susceptible to environmental changes.
Picture above: Grape DNA sources throughout Europe have been associated with ancient Roman seeds. Source: Grecaud Paul / Adobe Stock
By Ed Whelan