Differential Response of Wheat Rhizosphere Bacterial Community to Plant Variety and Fertilization

Abstract

The taxonomic assemblage and functions of the plant bacterial community are strongly influenced by soil and host plant genotype. Crop breeding, especially after the massive use of nitrogen fertilizers which led to varieties responding better to nitrogen fertilization, has implicitly modified the ability of the plant root to recruit an effective bacterial community. Among the priorities for harnessing the plant bacterial community, plant genotype-by-microbiome interactions are stirring attention. Here, we analyzed the effect of plant variety and fertilization on the rhizosphere bacterial community. In particular, we clarified the presence in the bacterial community of a varietal effect of N and P fertilization treatment. 16S rRNA gene amplicon sequence analysis of rhizospheric soil, collected from four wheat varieties grown under four N-P fertilization regimes, and quantification of functional bacterial genes involved in the nitrogen cycle (nifH; amoA; nirK and nosZ) were performed. Results showed that variety played the most important role and that treatments did not affect either bacterial community diversity or bacterial phyla abundance. Variety-specific response of rhizosphere bacterial community was detected, both in relation to taxa (Nitrospira) and metabolic functions. In particular, the changes related to amino acid and aerobic metabolism and abundance of genes involved in the nitrogen cycle (amoA and nosZ), suggested that plant variety may lead to functional changes in the cycling of the plant-assimilable nitrogen.

Wheat Rhizosphere Microbiota Respond to Changes in Plant Genotype, Chemical Inputs, and Plant Phenotypic Plasticity

“…Besides, in terms of community structures (beta diversity), breeding had a small effect on both bacterial and fungal communities (2.5-2.6%). Different but not opposite results were reported in the literature about the recent selection effort on rhizosphere microbial community structure: (i) no clear difference in bacterial community structure between ancient (three varieties) and modern (one variety) breeding types (Cangioli et al, 2022); (ii) stronger effect on 2. Only results from G, E, and G x E are shown.…”

Impact of conservation tillage on wheat performance and its microbiome

“…Wheat is one of the major crops worldwide, and its production is estimated to increase by 11% by 2026 ( Cangioli et al., 2022 ). Current management practices mainly rely on the application of external inputs such as pesticides for pest and disease control, mineral fertilizers to improve plant nutrition and biomass, and often irrigation to avoid water stress conditions.…”

“…Today, most studies have focused on the individual effect of single management practices on soil microbial communities, whereas only few studies investigated the combined effects of N fertilization, irrigation, and tillage ( Li et al., 2021 ; Cangioli et al., 2022 ). Rillig et al.…”

Diversity, community structure and potential functions of root-associated bacterial communities of different wheat (Triticum aestivum) cultivars under field conditions

“…Additionally, modern wheat cultivars selected under similar fertilization regimes will recruit different bacterial communities (Harman et al, 2020). These ndings have also been observed in, wheat plants grown under contrasted fertilization regimens and soil chemical properties, where the cultivars played the most important role in determining the diversity and structure of bacterial communities among rhizosphere and root endosphere samples (Cangioli et al 2022;Cordero et al, 2021) However, studies also have described that cultivar in uences on bacterial community composition are less than those observed for soil type and environmental factors (Dilla-Ermita et al 2021; Wipf and Coleman. 2021).…”