Scientists analysing 2,000-year-old grape seeds from ancient wells in Tuscany have mapped the most extensive genetic history of ancient grapevines recovered from a single site.
The findings, published in the Journal of Archaeological Science, show that ancient vineyards were part of the Roman Empire's highly sophisticated agricultural network that laid the foundation for modern winemaking.
The discovery was made at Cetamura del Chianti, a hilltop settlement in Italy's famous Chianti wine region. Between 300 BCE and 300 CE, local residents dropped grape pips into deep wells, where oxygen-free mud preserved them.
Dr Oya Inanli, who completed the work as part of her PhD at the University of York's Department of Archaeology, said: "We sequenced the DNA of 80 seeds and found a remarkable story of continuity. A large majority of the tested seeds belonged to a single, identical variety passed directly from the Etruscans to the Romans and maintained for centuries.
"We were also able to go a step further with the genetic testing and determine the colour of the ancient grapes. The markers revealed that this dominant, long-lived clone produced white berries."
The discovery of an overwhelming prevalence of white grapes at an ancient Chianti vineyard was a surprise as the region is globally famous today for its rich, red Sangiovese wines, although some white grapes are still grown in the area today.
Professor Nancy De Grummond, from Florida State University, said: "Our team's research adds an important chapter on the history of wine in the viticulture region of Chianti. What a delightful surprise to learn that the world-famous red wine of today was actually preceded by a white vintage that was curated and maintained for centuries in Etruscan and Roman times."
Following the Roman conquest of the settlement, entirely new grapevine varieties appeared at Cetamura, hinting at the introduction of 'choice varieties' from the expanding empire. In addition, the team found some evidence of the collection of some wild grapes, thanks to a method which examines the shape of the pips.
Genetic testing revealed that the dominant Cetamura clone was closely related to two ancient grape seeds previously tested from Southern France. This provides biological evidence of a wide-reaching agricultural trading network developed by the Romans to standardise wine production.
The team also found another ancient grape seed at Cetamura that belongs to a family of grapes still grown across Central and Eastern Europe today.
While its closest modern look-alike is a rare grape variety found in Hungary called Baratcsuha szurke, the discovery connects this ancient seed directly to a legendary, 400-year-old grapevine growing in Maribor, Slovenia.
This famous vine is officially recognized as the oldest living grapevine in the world that still produces fruit today.
Dr Nathan Wales, from the University of York's Department of Archaeology, said: "Our new findings show that this specific grape family is ancient and resilient. It is incredible to think that the wine grapes enjoyed by the ancient Romans are mere steps away from the varieties we pour into our glasses today.
"When you drink wine made from these relic varieties, you are tasting history that is just a stone's throw from what was served at Roman dinner tables thousands of years ago."
