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.

Several species of birds from different continents use and understand similar alarm calls when they see an invader that might lay an egg in their nest – this shared call hints at the origin of languag...

Plant roots release exudates to encourage microbiome assembly, which influences the function and stress resilience of plants. How specific exudates drive spatial colonization patterns remains largely ...

Abstract. Coevolution has come to be widely understood as specific, simultaneous, reciprocal adaptation by pairs of interacting species. This strict-sense

DNA methylation loss at transposable elements (TEs) can affect neighboring genes and be epigenetically inherited in plants, yet the determinants and significance of this additional system of inheritan...

Symbiotic interactions with mycorrhizal fungi and nitrogen-fixing bacteria synergistically enhance nitrogen transfer between plants via mycorrhizal networks. Our synthesis of 15N labeling studies rev...

Read the latest articles of Fungal Ecology at ScienceDirect.com, Elsevier’s leading platform of peer-reviewed scholarly literature