Rotation of hyphal in-growth cores has no confounding effects on soil abiotic properties

To disentangle effects of fungal hyphae and plant roots hyphal in-growth cores have become a common tool in research on arbuscular mycorrhizal fungi (AMF). However, it is unknown if the frequent rotation of a compartment has any side-effects that may hinder attributing findings to AMF. We set up an experiment with the presence/absence of a non-AMF microbial community, where each pot contained a rotated and a non-rotated soil core. The results show that within our rotation design soil parameters such as water content, soil structure, pH, and C and N concentrations are not influenced by the regular rotation in the absence of AMF. Our study therefore clearly underlines the validity of the rotated hyphal in-growth core as an experimental control for AMF growth and activity.