By Ekaterina Vislinskaya IWA
Our interview with Cristina Mercuri MW took place in early June and for our discussion I chose the timely topic of PIWI grape varieties (PIWI is a German acronym for pilzwiderstandsfähige — meaning “fungus-resistant” grape varieties).
Back in April, Cristina led a Vinitaly masterclass on PIWI varieties. The event had a limited number of seats and, unfortunately, I wasn’t able to attend. But that also highlighted something important: access to the material shared there was limited to the people in the room. I saw an opportunity to extend that conversation beyond Vinitaly and bring the latest insights on PIWI to a much wider international audience.
Cristina Mercuri MW
And who could do it better than Cristina Mercuri MW herself? She is not only a distinguished Master of Wine, she is also the first woman in Italy to earn that prestigious title. With her expertise and passion for innovation, she was the ideal person to guide us through the topic.
So, here are a few selected passages from our conversation.
The Birth of the PIWI Movement
Currently, there are 66 registered grape varieties in Europe classified as fungus-resistant grape varieties, or PIWIs. But how did it all begin? Cristina Mercuri MW takes us back to where it all started.
“The fundamental concept actually traces all the way back to the post-Phylloxera era. When Phylloxera devastated European vineyards in the late 19th century, the wine world realized that the key to survival lay in combining European grape varieties with the natural resistance of American vine species. The solution was to graft Vitis vinifera onto Phylloxera-resistant American rootstocks, rather than to cross the two species. Over time, scientists and viticulturists developed and selected rootstocks with specific characteristics, enabling them to better adapt vines to different soils, climates, vigour and yield requirements.”
The year 1999 marked a decisive turning point. A group of visionary viticulturists, led by Swiss researcher Dr. Pierre Basler, came together to formally organize the growing but still scattered efforts surrounding disease-resistant grape breeding.
Their goal was no longer just academic. It was a direct response to mounting environmental pressures: increasing fungicide resistance, stricter pesticide regulations, growing consumer demand for sustainability, and the looming threat of climate change.
Photo Credit: PIWI International
The initiative culminated in the creation of the international working group that would later become known as PIWI International, bringing together representatives of winegrowing institutions from Switzerland, Germany, Austria, Italy, France and Hungary. For the first time, breeders, winemakers and scientists from across Europe had a shared platform for exchanging knowledge, coordinating trials and promoting these varieties on a global stage.
The abbreviation PIWI, derived from the German Pilzwiderstandsfähige Rebsorten, meaning “fungus-resistant grape varieties”, had been used informally within the group since 1999. It first appeared in print in June 2000, giving the movement a memorable and marketable identity. The name was trademarked in 2004 and formally registered in 2015.
Cristina explains why she sometimes prefers a different term: “The term ‘PIWI’ is widely used in Italy and broader Europe. In other parts of the world, they go by different names, which is why I often prefer using the term FRG (Fungus-Resistant Grape varieties).”
PIWI International Wine Challenge 2026
Photo Credit: PIWI International
FRGs are gaining massive traction in marginal climates — whether that means regions facing extreme heat, extreme cold, or intense humidity. To understand what sets them apart, we have to look at the breeding process called “gene pyramiding”.
In the past, older hybrids were simple crosses between Vitis vinifera and non-vinifera varieties, often resulting in unappealing flavors. Modern FRGs are created through controlled pollination over generations. By continuously backcrossing a resistant non-vinifera variety with premium Vitis vinifera over decades, scientists accumulate multiple resistance genes.”
PIWI: More Than 20 Years On
More than two decades have passed since PIWI varieties began making their debut on the commercial wine scene. What started as an experiment has evolved into a strategic direction for sustainable winemaking, and into a genuine movement reshaping viticulture from Europe to the New World.
Today, PIWI is far more than a technical acronym. It represents a broader shift in the way we think about viticulture, one that prioritizes sustainability, reduced chemical inputs and resilience without necessarily sacrificing quality.
Cristina explains: “The result is a grape that genetically inherits 99% of its attributes from Vitis vinifera and only about 1% from the wild, resistant species. The ultimate purpose is to deliver a grapevine that naturally repels devastating fungal diseases while maintaining the exact flavor profile, elegance and quality that modern consumers expect from classic wine grapes.”
These varieties are also moving out of the niche into the spotlight as a credible long-term response to a changing climate.
The foundation of the movement in 1999 was therefore more than the birth of an organization. It was a moment when scattered breeding projects came together into a global movement — one that continues to influence the way the wine industry responds to the environmental challenges of the 21st century.
Cristina points to one particular striking advantage: “The scientific data accumulated over the last few years is incredibly fascinating. The primary, undisputed strength of these varieties is an approximate 80% reduction in vineyard treatments — fungicides and pesticides.”
Fewer chemical treatments mean fewer tractor passes through the vineyard, lower fuel consumption and potentially lower CO2 emissions, while also reducing the amount of chemicals applied to the soil.
Listen to Episode 2721of the Italian Wine Podcast to hear Cristina explain the benefits in greater detail.
But more than two decades of real-world experience have also produced a complex myriad of insights — some highly encouraging, others more challenging.
So what are the real takeaways after all these years?
Cristina gives her assessment:
“The primary downside right now is upfront cost. A young FRG vine from a nursery can cost up to three times more than a standard Vitis vinifera clone. However, when you look at a vineyard’s 5-to-10-year financial model, that initial investment is recouped incredibly quickly because your annual operational costs — fuel, labor, and chemical treatments — drop drastically.”
Italian PIWI: Leading Producers and Trends to Watch
Who led the way in Italy?
One of the movement’s pioneers and most prominent early “advocates” is Werner Morandell of the Lieselehof winery in South Tyrol/Alto Adige.
Inspired by the principles of sustainable viticulture, Morandell visited the University of Freiburg in 2000 and soon after began experimenting with fungus-resistant varieties such as Solaris, Bronner and Johanniter.
Lieselehof winery, Alto Adige, Italy
A historic milestone came in 2002, when he planted what is regarded as Italy’s first PIWI vineyard at an elevation of more than 1,000 metres above sea level.
The venture was anything but straightforward. At the time, national legislation had not yet caught up with these new varieties, and local authorities even ordered the vines to be ripped out. After a lengthy legal and bureaucratic battle, Morandell succeeded in securing their survival — and, in the process, helped make Italian viticultural history.
Today, Italy has authorized 36 PIWI varieties, with a particularly strong concentration in the north of the country — especially in Veneto, Trentino, Lombardia and Alto Adige.
These regions are dealing directly with increasingly erratic climate conditions: high humidity, sudden drought cycles, intense heatwaves, heavy rainfall and hail.
Among the producers currently working with these varieties are Terre di Ger in Friuli-Venezia-Giulia, Pizzolato in Veneto, Le Carline in Veneto and Friuli-Venezia-Giulia, Niedermayr in Alto Adige, Cantina La-Vis in Trentino, Lieselehof in Alto Adige, Tenuta J.Hofstätter in Alto Adige, and Nove Lune in Lombardia.
Cantina La-Vis in Trentino & Pizzolato in Veneto
What makes these wineries particularly important is that they are not simply growing PIWI grapes — they are helping define what premium FRG or PIWI wine can taste like.
Cristina highlights how quickly quality has evolved:
“Today, institutions like the Fondazione Edmund Mach in Trentino host annual blind-tasting festivals where critics, journalists and producers evaluate these wines. The standard we are seeing on the market today is absolutely outstanding. It is still a very young category, but in a relatively short window of time, we have made a monumental leap forward in quality.”
Fondazione Edmund Mach, San Michele all’Adige, Trentino, Italy
The 2026 PIWI International Wine Challenge also reflected the category’s growing momentum, with a record number of entries and international participation.
Cristina believes the ultimate sign of success will come when these wines no longer need to be treated as a separate category:
“In the next ten to twenty years, I expect these grapes to simply be integrated into regular regional tastings. If we are tasting the white wines of Veneto, an FRG wine should sit right alongside a traditional native wine. Consumers won’t view it as a strange hybrid anomaly — it will just be accepted as an organic, delicious part of our everyday wine culture. That is the goal of the global movement: to build reputation first, and then achieve beautiful normalcy.”
The winners of the 5th PIWI-wine award 2026 by the Fondazione Edmund Mach
Photo Credit: Fondazione Edmund Mach
One thing seems clear: PIWI varieties aren’t just part of the future — they’re already helping to shape it.
As Cristina Mercuri puts it:
“This is absolutely not a passing trend. Decades of rigorous international scientific research cannot be dismissed as a fad. However, I also do not believe they are the only future of wine. The true strength of the global wine industry lies in biodiversity and a richness of choices.”
The sector is likely to continue growing over the next decade, while the classics remain firmly rooted in the wine landscape. Rather than replacing one another, the two may increasingly exist side by side.
Either way, we’ll be watching closely.
There is much more to discover about PIWI grape varieties in the full conversation with Cristina Mercuri MW:
