Mikyeong Kim, Chungbuk National University

Yubeen Im, Jieun Song and Mikyeong Kim Department of Plant Medicine, Chungbuk National University, Cheongju 28644, Korea

Epidemiology, Evolution, and Diversity

Double-stranded RNA (dsRNA) viruses are widely distributed across biological kingdoms, yet their roles in plants remain significantly understudied compared to their counterparts in animals and fungi. This study addresses this gap by characterizing dsRNA viruses isolated from Choy sum (Brassica rapa subsp. chinensis) and pepper (Capsicum annuum). Using next-generation sequencing (NGS), we identified viruses belonging to the families Partitiviridae and Chrysoviridae. Specifically, raphanus sativus cryptic virus 2 (RsCV-2) and pepper cryptic virus 1 (PCV-1) were classified within the Partitiviridae, typically residing within or closely related to the genus Deltapartitivirus. These viruses exhibit bipartite genomes encoding an RNA-dependent RNA polymerase (RdRp) and a capsid protein, with high sequence conservation observed within plant host lineages. Phylogenetic analyses revealed compelling evidence of co-evolutionary relationships between these cryptic viruses and their hosts. Despite their widespread presence, these viruses induce no visible symptoms, suggesting a unique plant-virus equilibrium distinct from classical pathogenic interactions. Our findings expand current knowledge on the diversity and potential persistence of plant-associated dsRNA viruses. This study highlights the critical need to include plant models in dsRNA virus research to better understand host-virus interactions across biological systems and establish a foundation for further studies in this underexplored area.