This study evaluates the transcriptome of Arabidopsis thaliana seedlings growing in the presence of a diversity of synthetic bacteria communities under different phosphate availability. Overall design: Arabidopsis seeds (wild-type Col-0) were germinated on Johnson medium containing 0.5 % sucrose with either 1 mM Pi (in the form of KH2PO4), or no Pi added. Plants were then transferred to 30 µM Pi (low) or 100 µM Pi in the absence of sucrose alone or with one of the synthetic communities. Please note that the different values (e.g. I1I2, I2I3 etc.) in the 'sample characterics: bacteria' field represents different "synthetic communities" (ie groups of bacteria applied together). There are 9 blocks (P1,P2,P3,I1,I2,I3,N1,N2,N3) each of 8-9 bacterial strains, and each synthetic community is made by combining two blocks; for example, samples that say P1P2 were grown in the presence of a synthetic community that had all the strains from both P1 and P2.