A glimpse into the past of land plants and of their mycorrhizal affairs: from fossils to evo-devo

Arbuscular mycorrhizal (AM) fungi (AMF) have entered the mainstream of biology only in recent times, as a result of developments in DNA technologies and genomics, which are providing new tools to identify symbiont diversity, communication and development, and to reveal the contribution of each partner to the functioning of the symbiosis (Parniske, 2008; Bucher et al., 2009). In this issue of New Phytologist, Bin Wang and colleagues (pp. 514–525) indirectly demonstrated the antiquity of the plant–AM fungal association. They elegantly used molecular tools, in an evo-devo manner, to show that this widespread association is probably homologous in all lineages of land plants (Embryophyta).