Scientific selection: A century of increasing crop varietal diversity in US wheat.

A prevalent and persistent biodiversity concern is that modern cropping systems lead to an erosion in crop genetic diversity. Although certain trait uniformity provides advantages in crop management and marketing, farmers facing risks from change in climate, pests, and markets are also incentivized to adopt new varieties to address complex and spatially variable genetics, environment, and crop management interactions to optimize crop performance. In this study, we applied phylogenetically blind and phylogenetically informed diversity metrics to reveal significant increases in both the spatial and temporal diversity of the US wheat crop over the past century. Contrary to commonly held perceptions on the negative impact of modern cropping systems on crop genetic diversity, our results demonstrated a win-win outcome where the widespread uptake of scientifically selected varieties increased both crop production and crop diversity.