Aspen & mycorrhizal fungi mutualism


 the conversion of solar energy into chemical energy -

is the engine of life on this planet.

aspen fungi photoshop final.jpg

But in addition to sunlight and CO­2, photosynthesis requires other ingredients – such as nitrogen and phosphorous – that plants need to extract from the soil. Enter the fungi. Almost all plants are engaged in a cooperative symbiosis with fungi in which the root and fungal tissues intermingle to form a new absorptive organ called a mycorrhiza (myco = fungus, rhiza = root). Fungal bodies are made up networks of microscopic filaments (called hyphae) that are highly efficient at extracting simple compounds from complex substrates, like wood or soil. As a result, these fungal networks greatly improve plant nutrient uptake and enhance photosynthesis.

Mycorrhizal symbiosis originated nearly 500 million years ago, but many new forms of this symbiosis, involving tens of thousands of fungal species, have since evolved. Research in our lab attempts to understand and document the diversity of these fungi, and how their diversity influences emergent ecosystem properties, such as the structure of plant communities and the storage of carbon in the soil. Most recently we have been working with trees in the genus Populus – such as Aspen – and their mushroom forming mycorrhizal fungal partners. We hope that understanding the tripartite dynamics between Populus, mycorrizhal fungi, and their environment, will help ensure that ecosystems and biofuel crop systems are resilient in the face of future climate change.

For more information visit the Peay lab at



by Kabir Peay, PhD,

Professor of Biology, Stanford University