Arbuscular mycorrhizal fungi host preference and site effects in two plant species in a semiarid environment

► Plants associated to shrub in semiarid ecosystems show specific arbuscular mycorrhizal associations (AMF). ► We found higher AMF specificity in plants growing in open areas than in shrub patches. ► AMF genetic richness differed between species growing in open areas but not in shrub patches. ► Patchy distribution of soil resources and AMF communities greatly influence plant population and community dynamics.