Diversified cropping systems with complementary root growth strategies improve crop adaptation to and remediation of hostile soils

Background and aims Hostile soil conditions have a global impact on crop production. While root traits of individual plant species adapted to specific hostile soils are well studied, a comprehensive synthesis of how to use diversified cropping systems with complementary root growth strategies to adapt to and remediate hostile soils is lacking. Scope We begin by providing definitions, categorizations, and global distribution of hostile soils, followed by a synthesis of recent advances in below-ground niche complementarity or facilitative root interactions among crop species in diverse cropping systems across various hostile soils. Lastly, we highlight the significance of cultivating a robust understanding of root adaptations for crop diversification in hostile soils for future research. Conclusion Diversified cropping systems that incorporate complementary root growth strategies can efficiently utilize nutrients and mitigate abiotic stress in hostile soils, such as nutrient deficiency, aridity, and waterlogging conditions. Furthermore, intercropping hyperaccumulator plants or halophytes with crops is effective in reducing metal or salt accumulation in target crops grown in contaminated or saline-alkali soils, respectively. Cover crops could create biopores for succeeding crop roots in compacted soils, while diversified cropping systems aid in preventing additional soil erosion in eroded areas. Leveraging diverse root traits can also contribute to the suppression of soil‑borne diseases and pests within intercropping setups. Enhancing diversified cropping systems necessitates the application of novel methods and technologies for root studies. This multifaceted approach is crucial for sustaining yield under the challenges posed by multiple hostile soil conditions, especially within the context of climate change.