Divona – Agroscope’s New Disease-Resistant White Grape Variety
Bern, 30.10.2018 - Agroscope, the Swiss federal centre of excellence for agricultural research, is launching the first multiresistant white grape variety, Divona. The fruit of twenty years of research, Divona is resistant to fungal diseases, and well-suited for the production of high-quality wines – two characteristics that make it a popular variety for viticulture and winemaking.
Named in homage to the Celtic spring goddess, Divona helps promote ecologically friendly viticulture by reducing the use of plant-protection products. The new grape variety was christened last Tuesday 30 October on the occasion of an event organised by Agroscope and the canton of Geneva. A pioneer in viticulture trials, Geneva canton has been growing Divona in its vineyard since 2009. Head of Agroscope Eva Reinhard is delighted with the results: “Breeding allows us to develop disease-resistant varieties from which high-quality wines are produced.”
Agroscope’s First Multiresistant White Grape Variety
Produced from a cross between the varieties ‘Gamaret’ and ‘Bronner’, Divona shares the same parentage as her big brother, the red-wine variety Divico. The new variety boasts good resistance to botrytis blight (grey mould), and very high oenological potential thanks to Gamaret. From Bronner, it has inherited a high resistance to both powdery and downy mildew. ‘IRAC 2060’, Divona’s code name, was selected from among thousands of candidates on the basis of numerous agronomic, analytical and oenological criteria.
Very Good Cultivation Properties
Divona is an early-ripening grape variety (like Müller-Thurgau). This means that warmer winegrowing areas as well as soils with low water availability are to be avoided in its cultivation. In regions at risk of damage from birds, appropriate protection must be ensured. Divona has moderate vigour, a relatively upright habit, and high productivity, which often requires regulation of the harvest. Depending on disease pressure, only one to three treatments are needed for downy and powdery mildew during flowering and fruit set.
High Promise at Tastings
The wines produced from Divona grapes are rated very highly at tastings. They are structured and possess a fine bouquet, with exotic fruit and citrus flavours, often complemented by floral and mineral notes. The grape variety is already cultivated on a network of experimental plots throughout Switzerland, on farms with both integrated and organic production. Winemaking trials conducted at Agroscope as well as observations from the trial network enable the adaptation of Divona to different terroirs, and allow a fine-tuning of the winemaking methods that are most suitable for this grape variety.
High-Tech Breeding Programme
For 50 years now, Agroscope has developed numerous red and white grape varieties as part of its breeding programme. Classic crossing techniques (or hybridisation) made it possible to breed grape varieties with little susceptibility to grey mould (e.g. Gamaret and Garnoir). Since 1996, interspecific hybridisation techniques between European grapes and grape varieties with powdery- and downy-mildew resistance genes have been used in variety breeding. Both of these diseases require the numerous treatments typical of European viticulture, whether in integrated or organic production. These resistant grape varieties stem from wild species of American and Asian origin.
In order to expedite and optimise this process, Agroscope has developed a biochemical test technique for identifying resistant genotypes at the seedling stage. Potentially worthwhile candidates naturally synthesise compounds from the stilbene family to protect against fungal diseases. This approach allowed for the launch in 2013 of the first multiresistant red grape variety, Divico, whose development is highly promising. This has now been followed in 2018 by the first multiresistant white grape variety, Divona – to whose arrival we now propose a toast!
Address for enquiries
Jean-Laurent Spring, Head of the Viticulture Research Group, Agroscope
+41 58 468 65 63, email@example.com
Claire Bussy Pestalozzi, Agroscope Communication
+41 58 467 32 63, firstname.lastname@example.org
Last modification 03.10.2018