Cultivar mixtures stabilize wheat baking quality rather than improve it

Integrating diversity into agricultural systems represent a promising way to increase the resilience of crop production. In particular, cultivar mixtures are gaining attention in Europe because they are a practical way to stabilize wheat yields. However, the impact of these mixtures on wheat baking quality remains unclear. In this study, we examined the effects of cultivar mixtures on grain and flour quality. The experiment involved eight Swiss wheat cultivars grown in pure stands, in every possible 2-cultivar mixture, and in the 8-cultivar mixture. The experiment was repeated in eight year-by-site environments, allowing to evaluate the stability of baking quality in mixtures and pure stands. The results showed that the effects of the mixtures were negative for most flour quality parameters. Furthermore, these effects were not due to changes in cultivar proportions within the mixtures, but rather to cultivar-specific alterations in response to the mixture environment. Finally, mixtures significantly increased the stability of flour quality, by buffering the effects of fluctuating weather conditions. This study is the first to extensively investigate flour quality in eight contrasting environments. It demonstrates the potential of cultivar mixtures to mitigate the effects of changing abiotic conditions and ensure stable flour quality.