Study of the fungal bacterial and archaeal diversity associated with Triticum aestivum var. Paragon roots

Due to the harmful dysregulation of global biogeochemical cycles caused by agricultural pollution, we must find ecologically responsible means of controlling disease and promoting yields for crop like wheat. The root-associated microbiome may contribute to this goal, microbes can aid plants with disease suppression, abiotic stress relief and nutrient bioavailability. We applied 16S rRNA gene & fungal 18S rRNA gene (ITS2 region) amplicon sequencing to profile the diversity of the bacterial, archaeal & fungal communities associated with the roots of UK elite spring bread wheat variety Triticum aestivum var. Paragon. This revealed community composition shifted significantly for all three groups in the endosphere compared to the rhizosphere or soil. This shift was most pronounced for bacteria and fungi, while we observed weaker selection on the ammonia oxidising archaea dominated archaeal community. The microbiome was also profiled across multiple soil types; this showed soil inoculum was the primary driver of endosphere community composition, however several bacterial families were identified as core enriched taxa. The most abundant of these were Streptomycetaceae and Burkholderiaceae. Moreover, as the plant senesced both families were reduced in abundance, indicating input from the living plant was required to maintain endosphere abundance. To understand which taxa utilise wheat root exudates, plants were fed 13C CO2 in a DNA stable isotope probing experiment. While Streptomycetaceae were not shown to utilise root exudates in the rhizosphere, taxa within the Burkholderiaceae family and other core enriched taxa such as Pseudomonadaceae were. To utilise the capabilities of root-associated communities for agriculture, it is important to understand how the host interacts with the root community. We hope this understanding can lead to future yield improvement and biocontrol strategies.