Crop genetic diversity benefits farmland biodiversity in cultivated fields

• This is the first experimental test of the impact of crop diversity on biodiversity.
• Plots with higher crop genetic diversity hosted more diverse arthropod communities.
• Crop homogenization may thus contribute to biodiversity loss in agroecosystems.

This study tested whether increasing crop genetic diversity benefited farmland biodiversity in bread wheat (Triticum aestivum) fields, using an experimental approach in which arthropod and wild plant diversity were compared in a genetically homogeneous wheat variety vs. a variety mixture. The diversity of wild plant species was not affected by crop genetic diversity. However, we showed for the first time a positive impact of crop genetic diversity on below (collembola) and aboveground arthropod (spiders and predatory carabids) diversity at field scale in agroecosystems, which may be caused by a wider variety of food resources or more complex crop architecture. Increasing crop genetic diversity could therefore be an easy-to-implement scheme benefiting farmland biodiversity.