Abstract
Background and aims
Crop diversity has been repeatedly shown to support multiple ecosystem functions, both directly and indirectly, driven by interspecific root-root interactions. Despite continuous advances in this field, some research gaps remain, and we need to pay more attention to the design and management of multi-species and multi-cultivar systems in the future.
Scope
We review advances in intercropping in enhanced ecosystem functioning in competition-based and facilitation-based intercropping systems via root-root interactions. We also consider recent achievements in yield stability and soil fertility. We address several perspectives to focus on towards more sustainable agriculture via intercropping or cultivar mixtures in the future.
Conclusions
In competition-based systems, scramble competition via root-root competition and contest competition involving allelochemicals offset yield advantages of target crop species. However, niche differentiation and selection of desirable crop combinations to minimize negative effects through secondary metabolites may also help to gain yield advantages in intercropping and cultivar mixtures. In facilitation-based systems, selecting genotypes of facilitated species with root traits that best match the facilitator may strengthen the facilitative interactions in resource enrichment and disease and pest control. We need more long-term research to explore the effects of belowground processes on soil fertility, ecosystem stability, adaptation, and mitigation of climate change to establish sustainable agroecosystems in the future. It is also urgent to develop new methods to link belowground processes to functioning in multi-species and multi-cultivar agroecosystems.
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Acknowledgements
This review is written to celebrate the milestone that Hans Lambers has achieved by serving as Editor in Chief of Plant and Soil for 30 years, and to celebrate the friendship and the collaboration between Long Li and Hans Lambers for many years. Hans Lambers has collaborated with the intercropping research group at China Agricultural University to understand root-root interactions, especially provided leaf [Mn] as a proxy for carboxylate release, broadening the approach to explain interspecific P facilitation in multi-species community. This work was financially supported by the National Natural Science Foundation of China (Project Numbers: 32130067 and 31430014). Rui-Peng Yu was also financially supported by the National Natural Science Foundation of China (Project Numbers: 32101297). Hans Lambers received funding from the Deputy Vice Chancellor (Research) at the University of Western Australia.
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L.L. and R.P.Y. outlined the review. R.P.Y., H.Y. and Y.X. drafted the paper, and all authors contributed substantially to revisions.
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Yu, RP., Yang, H., Xing, Y. et al. Belowground processes and sustainability in agroecosystems with intercropping. Plant Soil 476, 263–288 (2022). https://doi.org/10.1007/s11104-022-05487-1
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DOI: https://doi.org/10.1007/s11104-022-05487-1