Contrasting Responses of Rhizosphere Bacterial, Fungal, Protist, and Nematode Communities to Nitrogen Fertilization and Crop Genotype in Field Grown Oilseed Rape (Brassica napus)

The rhizosphere microbiome is considered to play a key role in determining crop health. However, current understanding of the factors which shape assembly and composition heavily biased toward bacterial communities, relevance for other microbial groups unclear. Furthermore, community determined by variety factors, including host genotype, environment agricultural management practices, their relative importance interactions remain be elucidated. We investigated impact nitrogen fertilization on bacterial, fungal, nematode protist communities 10 contrasting oilseed rape genotypes field experiment. found significant differences bacteria, fungi, between bulk soil. Nitrogen application had but weak effect composition, this was associated with increased abundance complex fungal pathogens soil, Mycosphaerella sp. Leptosphaeria Network analysis showed that different effects connectivity soil rhizosphere. Crop genotype significantly affected evidence degree specificity number pathogens, L. maculans, Alternaria sp., Pyrenopeziza brassicae, Olpidium brassicae , biglobosa also potentially beneficial Heliotales root endophytes. no or communities. There relationship genetic distance extent dissimilarity Field disease assessment confirmed infection crops P. indicating sequencing an effective indicator plant conclude under conditions nutrient stoichiometry are health influencing roots pathogenic mutualistic stability interaction networks.