Impact of domestication and soil microbiome on rhizosphere bacterial community
Bacterial alpha diversity was significantly lower under DSM, whereas no effect of barley species was observed (Fig. 5a-c). Similarly, NMDS ordination analysis of overall community composition indicated the occurrence of distinct bacterial communities as a result of soil microbiome whereas barley species did not differ (Fig.5d). This was confirmed by the calculation of log2-fold changes between soil microbiome and barley species (Fig 5e). Although our results showed no significant effect of barley on the relative abundance of bacterial taxa, core microbiome analysis revealed differences between barley species (Fig 5f, Supplementary Table. 1). Interestingly, the number of barley-specific taxa was dependent on soil microbiome: besides a large core of 20 genera present in all groups, the effect of species was more pronounced under DSM treatment with four and five specific genera for modern and wild barley, respectively, and only five genera shared between both, whereas under NSM, almost all genera were shared between barley genotypes. The shared rich core consists mainly of members of Proteobacteria (7 of 14 genera), Actinobacteria (3 of 14 genera), and Acidobacteria (2 of 14 genera), which was different from the shared genera under DSM with mainly Armatimonadota (2 of 5 genera). Wild barley-specific genera under DSM belong to members of Proteobacteria and Verrucomicrobia, whereas mainly Chloroflexi were specific for modern barley.