Importance of agriculture for crop wild relatives conservation in Switzerland

While considered an essential part of the genetic diversity of plants, Crop Wild Relatives (CWR), are rarely the primary focus of conservation strategies. Despite this, a large portion of wild flora shares genetic relationships with cultivated species. The conservation of CWR presents not only a challenge to conservationists but also an opportunity to engage other sectors, such as agriculture, in a collaborative effort towards biodiversity preservation. Here, we quantified the association between agricultural areas and the distribution of CWR in Switzerland. To achieve this, we compiled a comprehensive checklist of Swiss CWR representing 2′227 taxa, identifying 285 taxa as priority CWR for Switzerland. Following a taxa-specific ecogeographic analysis, we analysed the extent to which priority CWR are already contained in existing protected areas as well as their distribution in the agricultural area. The observed species richness of priority CWR was compared to the modelled priority CWR richness to identify potential conservation gaps. Among the 285 priority CWR, 64 taxa (22.5%) are not significantly better covered by existing protected areas than a random species. However, 28.8% and 15.5% of these priority taxa are more frequently distributed in agricultural and summer grazing areas respectively than random expectations. A clear deficit of species richness of these priority CWR was inferred on lowlands, possibly related to a lower sampling effort. We further identified a minimal network of 39 complementary sites that contains all Swiss priority CWR and that could be used as a primary conservation infrastructure. Our results support better consideration of CWR in agricultural areas, an important “reservoir” for expanding specific measures of conservation.