Interactions between arbuscular mycorrhizal fungi, rhizobacteria, soil phosphorus and plant cytokinin deficiency change the root morphology, yield and quality of tobacco

► We studied intrinsic and extrinsic abiotic and biotic root morphology regulators. ► Plant cytokinin (CK) deficiency increased AMF hyphal root colonization. ► Pseudomonas fluorescens 8569r can function as mycorrhizal helper bacteria depending on CK. ► Interacting AMF, P. fluorescens 8569r, phosphorus and CK changed root morphology. ► Shoot yields were associated with altered root morphology.