Figure 6. Quantitative molecular analysis of genes of bacteria involved in the nitrogen cycle (nifH, amoA, nosZ, cmorB, nirK, narG, and nirS) in soils exposed to the biogenic silver nanoparticles (AgNP-T) at different concentrations, after 15, 30, 90, and 180 days post-treatment.

(A) Quantities of genes of bacteria associated with the nitrogen cycle; (B) Proportions of genes of bacteria associated with the nitrogen cycle. The zero soil was assigned a value of 1 and the other samples were quantified using this as a reference.