Modern maize hybrids have increased grain yield and efficiency tolerances to nitrogen-limited conditions

作者：Raziel A. Ordóñez, Lía B. Olmedo Pico, Antonella Ferela, Slobodan Trifunović, Douglas Eudy, Sotirios V. Archontoulis, Tony J. Vyn · 发表于：European Journal of Agronomy · 年份：2025 · DOI：10.1016/j.eja.2025.127621 · 被引用次数：16 · 研究领域：Crop Yield and Soil Fertility、Genetics and Plant Breeding、Rice Cultivation and Yield Improvement

Previous studies confirmed continued yield improvements in maize ( Zea mays L.) since the introduction of hybrids. However, corresponding yield genetic gains (GGs) and associated physiological changes occurring under low- nitrogen (N) conditions are less understood. This study assessed the growth, yield and key trait GGs of 38 non-GMO legacy hybrids under low- (34–99 kg N ha −1 ) versus high-N (202–280 kg N ha −1 ) conditions to understand the role of N in trait changes over time. Hybrids, commercialized in the USA by Bayer Crop Science from 1983 until 2020, were evaluated in eight site-years N trails at locations across Indiana, Illinois, and Iowa between 2020 and 2022. Seventeen traits were studied pre- and post-anthesis and at physiological maturity. The GGs for each trait are reported as Best Linear Unbiased Predictions (BLUPs), linked to the year of hybrid release. Grain yield increased by 88 kg ha −1 year −1 under low-N and 102 kg ha −1 year −1 under high-N. Over the past decade, modern hybrids grown under low-N outyielded older hybrids grown under high-N. Despite typical trade-offs between yield and grain N concentration, the grain C:N ratio increased in most recent hybrids subjected to low-N, indicating greater carbon (C) accumulation per unit of plant N uptake. Harvest index (HI) increased similarly under both N conditions, with no sign of a plateauing. Newly released hybrids displayed improved N use efficiency at maturity under low-N, and GGs in biomass accumulation...