Global systematic review with meta-analysis reveals yield advantage of legume-based rotations and its drivers

Diversified cropping systems, especially those including legumes, have been proposed to enhance food production with reduced inputs and environmental impacts. However, the impact of legume pre-crops on main crop yield and its drivers has never been systematically investigated in a global context. Here, we synthesize 11,768 yield observations from 462 field experiments comparing legume-based and non-legume cropping systems and show that legumes enhanced main crop yield by 20%. These yield advantages decline with increasing N fertilizer rates and crop diversity of the main cropping system. The yield benefits are consistent among main crops (e.g., rice, wheat, maize) and evident across pedo-climatic regions. Moreover, greater yield advantages (32% vs. 7%) are observed in low- vs. high-yielding environments, suggesting legumes increase crop production with low inputs (e.g., in Africa or organic agriculture). In conclusion, our study suggests that legume-based rotations offer a critical pathway for enhancing global crop production, especially when integrated into low-input and low-diversity agricultural systems. Crop rotations including legumes have been proposed as a strategy to enhance food production. Here, the authors conduct a global meta-analysis on legume-based crop rotations, showing that legume pre-crops increase 20% of yield in average across various crops and climatic regions.

Automated summary

Legume pre-crops in crop rotations can increase average crop yield by 20% across various crops and climatic regions, with greater benefits observed in low-input and low-diversity agricultural systems. The yield advantages decline with increasing nitrogen fertilizer rates and crop diversity. This study highlights the critical pathway offered by legume-based rotations for enhancing global crop production.