Viral tropism in plants, reproductive tissues, and seeds

Plant viral tropism refers to virus ability for infecting and replicating within specific cell types, tissues or hosts. Plant viral tropism is shaped by the absence of specific membrane-associated viral receptors and the supracellular nature of viral transport through plasmodesmata and vascular tissues. This review focuses on the molecular and cellular determinants of plant viral tropism, including modifications in plasmodesmal permeability, host-mediated RNA silencing, and tissue-specific viral protein localization. We discuss how certain viruses target reproductive organs, meristems, and seeds, overcoming antiviral barriers to establish persistent infections. Additionally, we explore the role of host factors in shaping viral distribution. Advances in super-resolution microscopy, single-cell transcriptomics, and proteomics have significantly expanded our ability to dissect virus-host interactions at the nanoscale, uncovering new mechanisms of viral accumulation. Understanding these processes is essential not only for improving crop resistance and designing integrated disease management strategies, but also for repurposing plant viruses as tools for targeted delivery and biotechnological applications.