Colombi, Tino
- Department of Soil and Environment, Swedish University of Agricultural Sciences
- University of Nottingham
Abstract
Plants form mycorrhizal symbioses to enhance nutrient acquisition, yet the biophysical principles governing carbon and nutrient exchange remain unclear. Here, we develop a theory of bi-directional carbon-nutrient transfer that integrates root anatomy, energetic costs, and mycorrhizal positioning. We show that nutrient uptake per unit carbon or energy investment declines with increasing root diameter due to higher carbon demands across thicker cortical tissues. Mycorrhizal fungi mitigate this constraint by enabling more carbon-efficient nutrient uptake, particularly when arbuscules are positioned in inner cortical layers. This spatial optimization minimizes the carbon cost of transporting nutrients to the stele. Our framework reconciles anatomical variation, symbiotic structure, and functional efficiency across root types and mycorrhizal strategies and offers a new lens for understanding the coevolution between roots and mycorrhizal fungi.
Published in
Nature Communications
2025, volume: 16, number: 1, article number: 8731
Publisher: NATURE PORTFOLIO
SLU Authors
UKÄ Subject classification
Microbiology
Ecology
Botany
Publication identifier
- DOI: https://doi.org/10.1038/s41467-025-64553-1
Permanent link to this page (URI)
https://res.slu.se/id/publ/144229