Cotton producers are interested in adopting conservation tillage for potential soil health benefits such as increasing soil microbial biomass. However, little is known about the resulting impacts of cover crops and tillage practices on soil microorganisms, especially plant beneficial microbes such as AMF abundance and interactions with cotton plants under dryland conditions. The objectives of this study were to evaluate soil microbial biomass and soil parameters in different tillage systems and cover crop rotations with dryland cotton, and to evaluate root colonization and AMF diversity in these treatments.