Mycorrhizal associations change root functionality: a 3D modelling study on competitive interactions between plants...

Area of Science:

• Plant Biology
• Ecology
• Computational Biology

Background:

• Root functional traits are increasingly understood through a two-dimensional framework, including a 'conservation' axis and a 'collaboration' axis.
• The 'collaboration' axis describes root strategies from 'do-it-yourself' (thin, branched roots) to 'outsourcing' nutrient uptake via arbuscular mycorrhizal fungi (AMF) (thick, sparsely branched roots).

Purpose of the Study:

• To investigate how interactions with AMF modify the influence of root traits on plant performance.
• To explore the functional significance of the root 'collaboration' axis in nutrient acquisition.

Main Methods:

• Development of a novel functional-structural plant (FSP) model.
• Simulation of plant competition for light and nutrients under conditions with and without AMF.

Main Results:

• In the absence of AMF, plants utilize thin, highly branched roots for nutrient uptake.
• AMF presence encourages the development of thick, unbranched roots, particularly for the uptake of immobile phosphorus.
• This AMF-mediated shift in root strategy was not observed for mobile nitrogen uptake.

Conclusions:

• The findings support a root trait framework that incorporates the interactive effects of roots and AMF.
• This study highlights the importance of considering soil microbial interactions, like those with AMF, in understanding root functionality and plant performance.
• The FSP modelling approach provides a valuable tool for integrating belowground trait expression and its consequences on plant-environment interactions.