In the German wine-growing region of Rheinland Palatinate, a state in southwestern Germany, both growers and consumers value traditional grape varieties.
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Cultivars like Riesling, Pinot Gris, Chardonnay, Cabernet Sauvignon and others have long been grown in the region, but they’re now facing threats on two fronts – a changing climate and regulatory pressure.
Why it matters: Experts predict a long-term loss of vineyards and landscape if no action is taken.
According to the Huglin Index, which is used to estimate the suitability of geographical regions for growing grape varieties, temperatures in southern Germany have been rising over the last 40 years, increasing pressure from fungal diseases like downy mildew, powdery mildew and botrytis.
At the same time, the European Union’s Green Deal means growers are losing access to crop protection products as the EU aims to cut use in half by 2030 under its Farm to Fork framework.
“Grape growers are happy to reduce plant protection, but they also want a crop and from my view, it’s not possible without some protection,” says professor Rheinhard Toepfer, head of the Julius-Kuehn-Institute for Grapevine Breeding Geilweilerhof.
“Do we want landscapes with viticulture and tourism? If we don’t, we can stop spraying but then we will have forests starting. It’s very simple.”
That’s why the team at the research station, which was first mentioned as a farm in the records of the nearby monastery in 1184, is working on new cultivars that allow growers to maintain quality and meet sustainability goals.
According to Toepfer, all of Germany’s popular cultivars are susceptible to fungal diseases. Growers have traditionally used crop protection products, but fungicide reduction brings a resurgence of other problems, like black rot.
photo:
Lilian Schaer
“Climate change is a huge problem because cultivars are losing their optimal window of cultivation, and although the EU says we need to reduce pesticides by 50 per cent by 2030, it is not realistic to achieve that in seven years,” he says.
“To be sustainable and fight climate change, we need new cultivars. These are the realities for viticulture in northern Europe.”
Breeding is not a quick fix, however. It can take up to 25 years from first seedling to approved cultivar, with breeders first and foremost looking at quality, followed by yield, disease and stress resistance and agronomic characteristics.
Calardis Blanc is a new class of cultivars called PIWI, short for Pilzwiderstandsfaehig, which means fungal resistant. It is showing resistance against powdery and downy mildew, black rot, botrytis and sun burn, while also meeting grower needs for quality and yield.
It was first crossed in 1993, received variety protection in 2018 and was approved for use in 2020, with approximately 125 acres grown in Germany as of 2022.
“It’s a fresh fruit wine with upright growth, making labour easier, and its high levels of resistance mean that plant protection savings of 70 to 80 per cent are possible (compared to traditional varieties),” says Toepfer, adding that some plant protection is still needed because resistance is not 100 per cent.
Of Germany’s approximately 247,000 acres of wine grape production, just over 8,600 acres are in PIWI varieties. Growers have been somewhat reluctant to adopt the new varieties, he notes, as they worry about performance, yield, and consumer acceptance.
Many vineyards are also steeped in centuries of tradition, but Toepfer believes in the PIWIs’ potential, estimating an overall possible market share of 20 to 30 per cent.
“There are blending options, as well as sparkling wines and Cuvée – there are lots of options to go into the market, but market introduction takes time. It’s an evolution, not a revolution, and it’s a question of storytelling,” he says, adding he believes the idea of climate-adapted wines will resonate with consumers.
For growers, he believes the loss of treatments combined with proven crop protection reduction and political pressure will be the impetus for more farmers to try PIWI varieties.
To date, 83 PIWI grape varieties are classified, registered and approved for grower use in Germany, with a further 131 numbered breeding strains that are showing promise.
