Wheat variety mixtures enhance yield stability and result in pronounced overyielding for certain line combinations

Abstract

Monocultures dominate crop production but face challenges such as vulnerability to pests, diseases, and environmental changes. To address this, growing mixtures of lines has gained attention for its potential to improve crop resilience. Our study investigated the overyielding effects of wheat mixtures compared to their individual lines under different management scenarios. Field trials conducted over two growing seasons at three locations in Germany included 46 inbred lines, 12 hybrids, and 94 mixtures tested under low- and high-input conditions. Results showed that wheat mixtures demonstrated both mid-component and better-component overyielding, with stronger effects under low-input conditions. Mid-component performance and general mixing ability were effective in predicting mixture performance, while trait differences of the pure lines and the heterogeneity index had little impact on overyielding effects. Instead, a negative correlation was found between better-component overyielding and yield differences. Mixtures exhibited significantly greater yield stability than pure stands across scenarios. Genotype-based stability indices further supported the enhanced stability of mixtures. These findings demonstrate the benefits of wheat variety mixtures in improving performance and stability, offering guidance for their effective use and highlighting the need for further research to improve mixture performance.