Microbial communities in the rhizosphere of tropical soils cultivated with maize as a function of nitrogen and phosphorus fertilizers.

Phosphorus (P) has a strong affinity with soil colloids in humid tropical conditions, reducing its availability to plants. The use of alternative sources of P can provide nutrients to plants and reduce countries' dependence on imports of phosphate fertilizers. Some nitrogen (N) sources can acidify the soil and affect the efficiency of P fertilizers. In this study, evaluated the changes in the microbial community of the rhizosphere of maize (Zea mays) affected by N and P fertilizers in soils with contrasting textures. The N sources used were calcium nitrate (CN) and ammonium sulphate (AS), and the P sources: triple superphosphate (TSP), organomineral (OR) and struvite (ST), and two control treatments without the addition of N and P fertilizers, with (Control) and without plant (Control NP). The rhizosphere samples were subjected to genetic sequencing of the 16S rRNA region, and the structures, diversity, richness and differential abundance of the microbial communities were assessed. Distinct microbial compositions were identified between medium-textured (MT) and clayey (CT) soils, influenced by soil texture, organic matter and fertilizers. Nitrogen fertilizers had the greatest impact on the structure of microbial communities in MT soil. Differential abundance analysis revealed specific variations in microbial taxa in response to nutrient sources, with an impact on nutrient cycling and acquisition. The ST + CN treatment in MT soil was enriched with pollutant bioremediating genera such as Sphingbium, Flavitalea, Devosia and Rubellimicrobium. The study highlights the intricate interaction between soil type, fertilizer sources and microbial community dynamics, with an impact on overall productivity.