Forests are of outstanding significance for mankind (timber, bioenergy, carbon sequestration). To guarantee an optimal activity of boreal and temperate forest ecosystems, the mutualistic interaction of tree roots with certain soil fungi (ectomycorrhiza) is a key element.

In forests, large portion of nitrogen and phosphorus is stored in the litter layer and is not available for trees. However, many ectomycorrhizal fungi can mobilize N/P from organic matter and enable thus a way to overcome nutritional limitation of trees.

In ectomycorrhizal symbiosis, plant roots and ectomycorrhizal fungi undergo a poorly understood developmental process. Soil growing hyphae isolate tree fine roots from soil by a thick fungal mantle. Fungal hyphae growing within the apoplast of the root cortex form a hyphal network where plant and fungal cells exchange nutrients.

We are investigating organ-formation and nutrient transfer between fungi and fine roots is organized, focusing on poplar as model.