Root-associated bacterial and fungal microbiomes of eight Brassica napus varieties

In this study, we selected eight Brassica napus varieties: an Argentine variety , Westar, NAM-12 , NAM-0, a commercial hybrid, an experimental hybrid, NAM-17, and NAM-72. We used amplicon sequencing of the bacterial 16S ribosomal RNA (rRNA) gene and the fungal Internal Transcribed Spacer (ITS) region to evaluate the root and rhizosphere microbiomes of the eight B. napus varieties at early vegetative and flowering stages. We conducted field trials at two experimental sites with different soil types under high and low N fertilizer application. We hypothesize that (i) environmental conditions, B. napus varieties, contrasting N fertilization and growth stages will impact the composition and structure of bacteria and fungal microbiomes in rhizosphere and root; (ii) high and low N application will produced different patterns of differentially abundant taxa of the eight B. napus varieties; and (iii) the greatest differences in the rhizosphere and root microbiomes will occur between early and modern B. napus varieties.