Impact of dimethylpyrazole-based nitrification inhibitors on soil-borne bacteria

Nitrogen (N) input from fertilizers modifies the properties of agricultural soils as well bacterial community diversity, composition and relationships. This can lead to negative impacts such deterioration system multifunctionality, whose maintenance is critical normal nutrient cycling. Synthetic nitrification inhibitors (NIs) be combined with improve efficiency N use by reducing losses. However, analysis their effects on non-target bacteria are scarce. study aimed analyze effect applying NIs DMPP DMPSA whole community. Through 16S rRNA amplicon sequencing we determined differences between samples in terms microbial co-occurrence networks. The application exerted little impact abundance dominant phyla. Nevertheless, several significant shifts were detected networks, particular taxa, where soil water content played a key role. For instance, intensified fertilization diversity under high water-filled pore spaces (WFPS) (>64%), whereas alpha-diversity was not affected at low WFPS (<55%). Interestingly, despite known inhibit ammonia monooxygenase (AMO) enzyme, both almost exclusively inhibited Nitrosomonas genera among AMO holding nitrifiers. Thus, showed reductions up 47% (DMPP) 66% (DMPSA). Nonetheless, abundances also shifted NI application. Notably, partially alleviated multifunctionality. A remarkable increase populations related Armatimonadetes (up +21%), Cyanobacteria +30%) Fibrobacteres +25%) observed when applied. substantially influenced associations decreasing complexity total edges node connectivity, increasing path distances.