In this project, GEMS trainee Danyang Duan will examine the effect of nitrogen fertilization history on soybean-Bradyrhizobium symbiosis, focusing on changes in the nodule microbiome and their implications for legume productivity. Utilizing varied nitrogen histories from the Morrow Plots in Illinois, she will evaluate the nitrogen impact on symbiotic relationships, plant yield, and nodule bacteriome diversity. The project aims to identify beneficial non-rhizobia endophytes within nodules through DNA sequencing of relevant genetic markers. By linking nodule microbial diversity with plant performance, the study seeks to enhance understanding of the role of nodule-associated bacteria in interacting with soybean and rhizobia, improving nitrogen fixation, and promoting sustainable agricultural practices.