<p>Potato brown rot disease can devastate potato production. Arbuscular mycorrhizal fungi (AMFs) are known to boost crop output. This study examines the interaction between AMFs and <i>Ralstonia solanacearum</i>, focusing on their effects on tuber yield and brown rot incidence. AMF increased the tuber yield by 68% (<i>P</i> = 0.03) in sandy soil and 30% (<i>P</i> = 0.047) in clay soil, along with an increase in HCO₃⁻ in sandy soil by 56% (<i>P</i> = 0.001) and a 24% increase in clay soil (<i>P</i> = 0.002). A 12% decrease in soil organic matter from 1.37 to 1.20% (<i>P</i> = 0.044) was recorded in sandy soil. AMF increased the pathogen populations in the rhizosphere from 3.2 to 7.8 (log CFU/g, <i>P</i> = 0.02) in sandy soil without a significant increase in Area&#xa0;Under the&#xa0;Disease&#xa0;Progression&#xa0;Curve. The pathogen decreased AMF colonization by 47% in sandy soil and 48% in clay soil, as well as sporulation by 63% in sandy and 57% in clay soils respectively (<i>P</i> &lt; 0.05 for all). It decreased the densities of phosphate-solubilizing bacteria from 6.19 up to 5.39 (<i>P</i> = 0.001) in sandy soil and from 6.04 to 5.16 (<i>P</i> = 0.008) in clay soil. Additionally, the pathogen decreased the silicate-solubilizing bacteria from 6.94 to 5.32 (<i>P</i> &lt; 0.001) in sandy and from 6.82 up to 6.17 (<i>P</i> = 0.04) in clay soils respectively. In conclusion, while AMF significantly increased potato yield, it is not recommended for soils infested with <i>R. solanacearum</i> due to the potential increase in disease risk.</p> Graphical Abstract <p></p>