This study characterized dsDNA viral diversity in biochar-amended agricultural soils using paired total metagenomes and viromes (viral size fraction metagenomes). Size fractionation in viromes reduced non-viral DNA, revealing greater viral richness, taxonomic diversity, predicted host range, and access to rare viruses compared to total metagenomes, which primarily captured abundant vOTUs. Of 2961 vOTUs, 2684 were exclusive to viromes. Both viral and microbial communities showed significant temporal changes, suggesting coupled responses to rhizosphere processes and nitrogen amendments. Viral communities were also spatially structured. The study highlights the utility of soil viromics and reveals similarities and differences in viral and microbial community dynamics.

Christian Santos-Medellin, Laura A. Zinke, Anneliek M. ter Horst, Danielle L. Gelardi, Sanjai J. Parikh, Joanne B. Emerson