Safeguarding the Genetic Diversity of Arvine
Photo: Agroscope
A programme has been launched for safeguarding the genetic diversity of Arvine, a grape variety formerly cultivated in Valais. Directed selection would make it possible to exploit this variety’s biodiversity and to meet the ecological and economic challenges of the future.
A programme for safeguarding the (intra-varietal) clonal diversity of the main indigenous and traditional grape varieties of Valais has been launched involving the collaboration of several actors such as the Society of Vineyard Nurserymen of Valais, the Office of Vine and Wine of the Canton of Valais and Agroscope.
Arvine – an age-old grape variety
Arvine – also called ‘Petite Arvine’ – is a grape variety cultivated primarily in Switzerland, in the Canton of Valais. Recent studies suggest that Arvine might be a very old grape variety indeed. Its presence in Valais was first reported in the 17th century, making it one of the local specialities. Long cultivated on small plots of land, this grape variety has enjoyed a certain popularity in Valais vineyards in recent years, and the land area devoted to it has increased dramatically.
Studying biodiversity
In the case of Arvine, surveys were carried out from 1992 onwards in old pre-clone era vines. Individuals (clones) representing the diversity of the grape variety were selected. After elimination of the virus-infected individuals, around a hundred clones were included in the nuclear stock for the purpose of preserving and studying the biodiversity of Arvine. Observations revealed the existence of substantial (intra-varietal) clonal diversity for the majority of the agronomic aspects, particularly for production potential, sensitivity to Botrytis cinerea, nitrogen content, aromatic precursor content and must acidity. This diversity could be exploited through polyclonal selection.
Assessing the value of the polyclonal selections
At the conclusion of this clonal biodiversity characterisation process, Arvine appears to exhibit great intra-varietal diversity. Polyclonal selection could represent a means of exploiting this diversity. A project was launched in 2022 at the Viticulture and Oenology Experimental Station in Valais to objectively assess the value or otherwise of the polyclonal selections applied to the Arvine grape variety. The aim of this trial, set up on the Grand Brûlé estate in spring 2023, is to evaluate the usefulness of directed polyclonal selections as a tool for meeting the challenges posed by changes in the climate and in cultivation techniques.
Conclusions
- Arvine is a grape variety formerly cultivated in Valais. A survey of old Arvine vines was conducted from 1992 onwards to safeguard the clonal diversity of this grape variety. This project is the result of a collaboration between Agroscope, the Office of Vine and Wine of the Canton of Valais and the Society of Vineyard Nurserymen of Valais.
- The characterisation of the 91 Arvine clones safeguarded by the project has revealed substantial clonal diversity in this grape variety for the majority of agronomic parameters studied.
- This clonal biodiversity could be exploited via directed polyclonal selections. This approach must be evaluated objectively to determine the pros and cons regarding its relevance when faced with the current and future challenges of Valais vineyards.
- To this end, five polyclonal selections were created with defined priorities (yield potential, must composition: acidity, nitrogen content and aromatic precursors). These selections will be subject to agronomic and oenological evaluation.
Bibliographical reference
Diversité intra-variétale et sélection polyclonale pour l’Arvine.