The roots of change: global change and mycorrhizal symbioses through the Phanerozoic

Fungi and plants have engaged in intimate symbioses that are now globally widespread and have driven terrestrial biogeochemical processes since plant terrestrialisation >500 Mya.

Fossil evidence indicates that the earliest land plants, which evolved in a high CO2 atmosphere, hosted diverse fungal symbionts. It is generally thought that the rise of early non-vascular plants and the later evolution of plant roots and vasculature drove the long-term shift towards a high-oxygen, low-CO2 atmosphere and climate that eventually permitted the evolution of mammals and, ultimately, humans.

Such shifts in atmospheric CO2 concentration, together with biotic factors such as plant and fungal identity, have been shown to impact exchanges of carbon for nutrients between plants and their mycorrhizal fungi. The effects of atmospheric CO2 concentrations and cultivar on crop-fungal carbon-for-nutrient exchanges remain critical knowledge gaps in the exploitation of mycorrhizas for future sustainable agriculture in a changing climate.

We are investigating the impact of climate change-relevant shifts in atmospheric CO2 concentrations in mycorrhizas in both wild and domesticated plants. Our research suggests that mycorrhizas could contribute to sustainable crop production as part of a wider sustainable agriculture strategy and that there is substantial potential to improve future crop mycorrhizal receptivity, function and CO2 responsiveness.