Sharing Pollinators and Viruses: Virus Diversity of Pollen in a Co-Flowering Community

Co-flowering plant species frequently share pollinators, flower-inhabiting bacteria, and fungi, but whether pollen-associated viruses are shared is unknown. Given that pollen-associated viruses are sexually transmitted diseases, their diversity is expected to increase with pollinator sharing. We conducted a metagenomic study to identify pollen-associated viruses from 18 co-flowering plant species to determine whether (1) life history, floral traits, or pollination generalism were associated with viral richness, and (2) plants shared pollen-associated viruses. We demonstrated that pollination generalism influences pollen-associated virus richness and the extent of pollen virus sharing between plant species. We also revealed that perenniality, multiple flowers, and bilateral floral symmetry were associated with high pollen viral richness locally, confirming and extending patterns observed previously at a continental scale. Our results highlight the importance of plant-pollinator interactions as drivers of plant-viral interaction diversity.