Climate and agronomy, not genetics, underpin recent maize yield gains in favorable environments

Authors

Gonzalo Rizzo, University of Nebraska at Lincoln
Juan Pablo Monzon, University of Nebraska at Lincoln
Fatima Amor Tenorio, University of Nebraska at LincolnFollow
Réka Howard, University of Nebraska-LincolnFollow
Kenneth G. Cassman, University of Nebraska at LincolnFollow
Patricio Grassini, University of Nebraska-LincolnFollow

Date of this Version

12-6-2021

Citation

PNAS 2022 Vol. 119 No. 4 e2113629119. https://doi.org/10.1073/pnas.2113629119

Comments

open access

Abstract

Quantitative understanding of factors driving yield increases of major food crops is essential for effective prioritization of research and development. Yet previous estimates had limitations in distinguishing among contributing factors such as changing climate and new agronomic and genetic technologies. Here, we distinguished the separate contribution of these factors to yield advance using an extensive database collected from the largest irrigated maize-production domain in the world located in Nebraska (United States) during the 2005-to-2018 period. We found that 48% of the yield gain was associated with a decadal climate trend, 39% with agronomic improvements, and, by difference, only 13% with improvement in genetic yield potential. The fact that these findings were so different from most previous studies, which gave much-greater weight to genetic yield potential improvement, gives urgency to the need to reevaluate contributions to yield advances for all major food crops to help guide future investments in research and development to achieve sustainable global food security. If genetic progress in yield potential is also slowing in other environments and crops, future crop-yield gains will increasingly rely on improved agronomic practices.